Welcome to PyFilesystem2’s documentation!

Contents:

Introduction

PyFilesystem is a Python module that provides a common interface to any filesystem.

Think of PyFilesystem FS objects as the next logical step to Python’s file objects. In the same way that file objects abstract a single file, FS objects abstract an entire filesystem.

Installing

You can install PyFilesystem with pip as follows:

pip install fs

Or to upgrade to the most recent version:

pip install fs --upgrade

Alternatively, if you would like to install from source, you can check out the code from Github.

Guide

The PyFilesytem interface simplifies most aspects of working with files and directories. This guide covers what you need to know about working with FS objects.

Why use PyFilesystem?

If you are comfortable using the Python standard library, you may be wondering; why learn another API for working with files?

The PyFilesystem API is generally simpler than the os and io modules – there are fewer edge cases and less ways to shoot yourself in the foot. This may be reason alone to use it, but there are other compelling reasons you should use import fs for even straightforward filesystem code.

The abstraction offered by FS objects means that you can write code that is agnostic to where your files are physically located. For instance, if you wrote a function that searches a directory for duplicates files, it will work unaltered with a directory on your hard-drive, or in a zip file, on an FTP server, on Amazon S3, etc.

As long as an FS object exists for your chosen filesystem (or any data store that resembles a filesystem), you can use the same API. This means that you can defer the decision regarding where you store data to later. If you decide to store configuration in the cloud, it could be a single line change and not a major refactor.

PyFilesystem can also be beneficial for unit-testing; by swapping the OS filesystem with an in-memory filesystem, you can write tests without having to manage (or mock) file IO. And you can be sure that your code will work on Linux, MacOS, and Windows.

Opening Filesystems

There are two ways you can open a filesystem. The first and most natural way is to import the appropriate filesystem class and construct it.

Here’s how you would open a OSFS (Operating System File System), which maps to the files and directories of your hard-drive:

>>> from fs.osfs import OSFS
>>> home_fs = OSFS("~/")

This constructs an FS object which manages the files and directories under a given system path. In this case, '~/', which is a shortcut for your home directory.

Here’s how you would list the files/directories in your home directory:

>>> home_fs.listdir('/')
['world domination.doc', 'paella-recipe.txt', 'jokes.txt', 'projects']

Notice that the parameter to listdir is a single forward slash, indicating that we want to list the root of the filesystem. This is because from the point of view of home_fs, the root is the directory we used to construct the OSFS.

Also note that it is a forward slash, even on Windows. This is because FS paths are in a consistent format regardless of the platform. Details such as the separator and encoding are abstracted away. See Paths for details.

Other filesystems interfaces may have other requirements for their constructor. For instance, here is how you would open a FTP filesystem:

>>> from ftpfs import FTPFS
>>> debian_fs = FTPFS('ftp.mirror.nl')
>>> debian_fs.listdir('/')
['debian-archive', 'debian-backports', 'debian', 'pub', 'robots.txt']

The second, and more general way of opening filesystems objects, is via an opener which opens a filesystem from a URL-like syntax. Here’s an alternative way of opening your home directory:

>>> from fs import open_fs
>>> home_fs = open_fs('osfs://~/')
>>> home_fs.listdir('/')
['world domination.doc', 'paella-recipe.txt', 'jokes.txt', 'projects']

The opener system is particularly useful when you want to store the physical location of your application’s files in a configuration file.

If you don’t specify the protocol in the FS URL, then PyFilesystem will assume you want a OSFS relative from the current working directory. So the following would be an equivalent way of opening your home directory:

>>> from fs import open_fs
>>> home_fs = open_fs('.')
>>> home_fs.listdir('/')
['world domination.doc', 'paella-recipe.txt', 'jokes.txt', 'projects']

Tree Printing

Calling tree() on a FS object will print an ascii tree view of your filesystem. Here’s an example:

>>> from fs import open_fs
>>> my_fs = open_fs('.')
>>> my_fs.tree()
├── locale
│   └── readme.txt
├── logic
│   ├── content.xml
│   ├── data.xml
│   ├── mountpoints.xml
│   └── readme.txt
├── lib.ini
└── readme.txt

This can be a useful debugging aid!

Closing

FS objects have a close() methd which will perform any required clean-up actions. For many filesystems (notably OSFS), the close method does very little. Other filesystems may only finalize files or release resources once close() is called.

You can call close explicitly once you are finished using a filesystem. For example:

>>> home_fs = open_fs('osfs://~/')
>>> home_fs.settext('reminder.txt', 'buy coffee')
>>> home_fs.close()

If you use FS objects as a context manager, close will be called automatically. The following is equivalent to the previous example:

>>> with open_fs('osfs://~/') as home_fs:
...    home_fs.settext('reminder.txt', 'buy coffee')

Using FS objects as a context manager is recommended as it will ensure every FS is closed.

Directory Information

Filesystem objects have a listdir() method which is similar to os.listdir; it takes a path to a directory and returns a list of file names. Here’s an example:

>>> home_fs.listdir('/projects')
['fs', 'moya', 'README.md']

An alternative method exists for listing directories; scandir() returns an iterable of Resource Info objects. Here’s an example:

>>> directory = list(home_fs.scandir('/projects'))
>>> directory
[<dir 'fs'>, <dir 'moya'>, <file 'README.md'>]

Info objects have a number of advantages over just a filename. For instance you can tell if an info object references a file or a directory with the is_dir attribute, without an additional system call. Info objects may also contain information such as size, modified time, etc. if you request it in the namespaces parameter.

Note

The reason that scandir returns an iterable rather than a list, is that it can be more efficient to retrieve directory information in chunks if the directory is very large, or if the information must be retrieved over a network.

Additionally, FS objects have a filterdir() method which extends scandir with the ability to filter directory contents by wildcard(s). Here’s how you might find all the Python files in a directory:

>>> code_fs = OSFS('~/projects/src')
>>> directory = list(code_fs.filterdir('/', files=['*.py']))

By default, the resource information objects returned by scandir and listdir will contain only the file name and the is_dir flag. You can request additional information with the namespaces parameter. Here’s how you can request additional details (such as file size and file modified times):

>>> directory = code_fs.filterdir('/', files=['*.py'], namespaces=['details'])

This will add a size and modified property (and others) to the resource info objects. Which makes code such as this work:

>>> sum(info.size for info in directory)

See Resource Info for more information.

Sub Directories

PyFilesystem has no notion of a current working directory, so you won’t find a chdir method on FS objects. Fortunately you won’t miss it; working with sub-directories is a breeze with PyFilesystem.

You can always specify a directory with methods which accept a path. For instance, home_fs.listdir('/projects') would get the directory listing for the projects directory. Alternatively, you can call opendir() which returns a new FS object for the sub-directory.

For example, here’s how you could list the directory contents of a projects folder in your home directory:

>>> home_fs = open_fs('~/')
>>> projects_fs = home_fs.opendir('/projects')
>>> projects_fs.listdir('/')
['fs', 'moya', 'README.md']

When you call opendir, the FS object returns an instance of a SubFS. If you call any of the methods on a SubFS object, it will be as though you called the same method on the parent filesystem with a path relative to the sub-directory.

The makedir and makedirs methods also return SubFS objects for the newly create directory. Here’s how you might create a new directory in ~/projects and initialize it with a couple of files:

>>> home_fs = open_fs('~/')
>>> game_fs = home_fs.makedirs('projects/game')
>>> game_fs.touch('__init__.py')
>>> game_fs.settext('README.md', "Tetris clone")
>>> game_fs.listdir('/')
['__init__.py', 'README.md']

Working with SubFS objects means that you can generally avoid writing much path manipulation code, which tends to be error prone.

Working with Files

You can open a file from a FS object with open(), which is very similar to io.open in the standard library. Here’s how you might open a file called “reminder.txt” in your home directory:

>>> with open_fs('~/') as home_fs:
...     with home_fs.open('reminder.txt') as reminder_file:
...        print(reminder_file.read())
buy coffee

In the case of a OSFS, a standard file-like object will be returned. Other filesystems may return a different object supporting the same methods. For instance, MemoryFS will return a io.BytesIO object.

PyFilesystem also offers a number of shortcuts for common file related operations. For instance, getbytes() will return the file contents as a bytes, and gettext() will read unicode text. These methods is generally preferable to explicitly opening files, as the FS object may have an optimized implementation.

Other shortcut methods are setbin(), setbytes(), settext().

Walking

Often you will need to scan the files in a given directory, and any sub-directories. This is known as walking the filesystem.

Here’s how you would print the paths to all your Python files in your home directory:

>>> from fs import open_fs
>>> home_fs = open_fs('~/')
>>> for path in home_fs.walk.files(filter=['*.py']):
...     print(path)

The walk attribute on FS objects is instance of a BoundWalker, which should be able to handle most directory walking requirements.

See Walking for more information on walking directories.

Moving and Copying

You can move and copy file contents with move() and copy() methods, and the equivalent movedir() and copydir() methods which operate on directories rather than files.

These move and copy methods are optimized where possible, and depending on the implementation, they may be more performant than reading and writing files.

To move and/or copy files between filesystems (as apposed to within the same filesystem), use the move and copy modules. The methods in these modules accept both FS objects and FS URLS. For instance, the following will compress the contents of your projects folder:

>>> from fs.copy import copy_fs
>>> copy_fs('~/projects', 'zip://projects.zip')

Which is the equivalent to this, more verbose, code:

>>> from fs.copy import copy_fs
>>> from fs.osfs import OSFS
>>> from fs.zipfs import ZipFS
>>> copy_fs(OSFS('~/projects'), ZipFS('projects.zip'))

The copy_fs() and copy_dir() functions also accept a Walker parameter, which can you use to filter the files that will be copied. For instance, if you only wanted back up your python files, you could use something like this:

>>> from fs.copy import copy_fs
>>> from fs.walk import Walker
>>> copy_fs('~/projects', 'zip://projects.zip', walker=Walker(filter=['*.py']))

An alternative to copying is mirroring, which will copy a filesystem them keep it up to date by copying only changed files / directories. See mirror().

Concepts

The following describes some core concepts when working with PyFilesystem. If you are skimming this documentation, pay particular attention to the first section on paths.

Paths

With the possible exception of the constructor, all paths in a filesystem are PyFilesystem paths, which have the following properties:

  • Paths are str type in Python3, and unicode in Python2
  • Path components are separated by a forward slash (/)
  • Paths beginning with a / are absolute
  • Paths not beginning with a forward slash are relative
  • A single dot (.) means ‘current directory’
  • A double dot (..) means ‘previous directory’

Note that paths used by the FS interface will use this format, but the constructor may not. Notably the OSFS constructor which requires an OS path – the format of which is platform-dependent.

Note

There are many helpful functions for working with paths in the path module.

PyFilesystem paths are platform-independent, and will be automatically converted to the format expected by your operating system – so you won’t need to make any modifications to your filesystem code to make it run on other platforms.

System Paths

Not all Python modules can use file-like objects, especially those which interface with C libraries. For these situations you will need to retrieve the system path. You can do this with the getsyspath() method which converts a valid path in the context of the FS object to an absolute path that would be understood by your OS.

For example:

>>> from fs.osfs import OSFS
>>> home_fs = OSFS('~/')
>>> home_fs.getsyspath('test.txt')
'/home/will/test.txt'

Not all filesystems map to a system path (for example, files in a MemoryFS will only ever exists in memory).

If you call getsyspath on a filesystem which doesn’t map to a system path, it will raise a NoSysPath exception. If you prefer a look before you leap approach, you can check if a resource has a system path by calling hassyspath()

Sandboxing

FS objects are not permitted to work with any files outside of their root. If you attempt to open a file or directory outside the filesystem instance (with a backref such as "../foo.txt"), a IllegalBackReference exception will be thrown. This ensures that any code using a FS object won’t be able to read or modify anything you didn’t intend it to, thus limiting the scope of any bugs.

Unlike your OS, there is no concept of a current working directory in PyFilesystem. If you want to work with a sub-directory of an FS object, you can use the opendir() method which returns another FS object representing the contents of that sub-directory.

For example, consider the following directory structure. The directory foo contains two sub-directories; bar and baz:

--foo
  |--bar
  |  |--readme.txt
  |  `--photo.jpg
  `--baz
     |--private.txt
     `--dontopen.jpg

We can open the foo directory with the following code:

from fs.osfs import OSFS
foo_fs = OSFS('foo')

The foo_fs object can work with any of the contents of bar and baz, which may not be desirable if we are passing foo_fs to a function that has the potential to delete files. Fortunately we can isolate a single sub-directory with the opendir() method:

bar_fs = foo_fs.opendir('bar')

This creates a completely new FS object that represents everything in the foo/bar directory. The root directory of bar_fs has been re- position, so that from bar_fs’s point of view, the readme.txt and photo.jpg files are in the root:

--bar
  |--readme.txt
  `--photo.jpg

Note

This sandboxing only works if your code uses the filesystem interface exclusively. It won’t prevent code using standard OS level file manipulation.

Errors

PyFilesystem converts errors in to a common exception hierarchy. This ensures that error handling code can be written once, regardless of the filesystem being used. See errors for details.

Resource Info

Resource information (or info) describes standard file details such as name, type, size, etc., and potentially other less-common information associated with a file or directory.

You can retrieve resource info for a single resource by calling getinfo(), or by calling scandir() which returns an iterator of resource information for the contents of a directory. Additionally, filterdir() can filter the resources in a directory by type and wildcard.

Here’s an example of retrieving file information:

>>> from fs.osfs import OSFS
>>> fs = OSFS('.')
>>> fs.settext('example.txt', 'Hello, World!')
>>> info = fs.getinfo('example.txt', namespaces=['details'])
>>> info.name
'example.txt'
>>> info.is_dir
False
>>> info.size
13

Info Objects

PyFilesystem exposes the resource information via properties of Info objects.

Namespaces

All resource information is contained within one of a number of potential namespaces, which are logical key/value groups.

You can specify which namespace(s) you are interested in with the namespaces argument to getinfo(). For example, the following retrieves the details and access namespaces for a file:

resource_info = fs.getinfo('myfile.txt', namespaces=['details', 'access'])

In addition to the specified namespaces, the fileystem will also return the basic namespace, which contains the name of the resource, and a flag which indicates if the resource is a directory.

Basic Namespace

The basic namespace is always returned. It contains the following keys:

Name Type Description
name str Name of the resource.
is_dir bool A boolean that indicates if the resource is a directory.

The keys in this namespace can generally be retrieved very quickly. In the case of OSFS the namespace can be retrieved without a potentially expensive system call.

Details Namespace

The details namespace contains the following keys.

Name type Description
accessed datetime The time the file was last accessed.
created datetime The time the file was created.
metadata_changed datetime The time of the last metadata (e.g. owner, group) change.
modified datetime The time file data was last changed.
size int Number of bytes used to store the resource. In the case of files, this is the number of bytes in the file. For directories, the size is the overhead (in bytes) used to store the directory entry.
type ResourceType Resource type, one of the values defined in ResourceType.

The time values (accessed_time, created_time etc.) may be None if the filesystem doesn’t store that information. The size and type keys are guaranteed to be available, although type may be unknown if the filesystem is unable to retrieve the resource type.

Access Namespace

The access namespace reports permission and ownership information, and contains the following keys.

Name type Description
gid int The group ID.
group str The group name.
permissions Permissions An instance of Permissions, which contains the permissions for the resource.
uid int The user ID.
user str The user name of the owner.

This namespace is optional, as not all filesystems have a concept of ownership or permissions. It is supported by OSFS. Some values may be None if they aren’t supported by the filesystem.

Stat Namespace

The stat namespace contains information reported by a call to os.stat. This namespace is supported by OSFS and potentially other filesystems which map directly to the OS filesystem. Most other filesystems will not support this namespace.

LStat Namespace

The lstat namespace contains information reported by a call to os.lstat. This namespace is supported by OSFS and potentially other filesystems which map directly to the OS filesystem. Most other filesystems will not support this namespace.

Other Namespaces

Some filesystems may support other namespaces not covered here. See the documentation for the specific filesystem for information on what namespaces are supported.

You can retrieve such implementation specific resource information with the get() method.

Note

It is not an error to request a namespace (or namespaces) that the filesystem does not support. Any unknown namespaces will be ignored.

Missing Namespaces

Some attributes on the Info objects require that a given namespace be present. If you attempt to reference them without the namespace being present (because you didn’t request it, or the filesystem doesn’t support it) then a MissingInfoNamespace exception will be thrown. Here’s how you might handle such exceptions:

try:
    print('user is {}'.format(info.user))
except errors.MissingInfoNamespace:
    # No 'access' namespace
    pass

If you prefer a look before you leap approach, you can use use the has_namespace() method. Here’s an example:

if info.has_namespace('access'):
    print('user is {}'.format(info.user))

See Info for details regarding info attributes.

Raw Info

The Info class is a wrapper around a simple data structure containing the raw info. You can access this raw info with the info.raw property.

Note

The following is probably only of interest if you intend to implement a filesystem yourself.

Raw info data consists of a dictionary that maps the namespace name on to a dictionary of information. Here’s an example:

{
    'access': {
        'group': 'staff',
        'permissions': ['g_r', 'o_r', 'u_r', 'u_w'],
        'user': 'will'
    },
    'basic': {
        'is_dir': False,
        'name': 'README.txt'
    },
    'details': {
        'accessed': 1474979730.0,
        'created': 1462266356.0,
        'metadata_changed': 1473071537.0,
        'modified': 1462266356.0,
        'size': 79,
        'type': 2
    }
}

Raw resource information contains basic types only (strings, numbers, lists, dict, None). This makes the resource information simple to send over a network as it can be trivially serialized as JSON or other data format.

Because of this requirement, times are stored as epoch times. The Info object will convert these to datetime objects from the standard library. Additionally, the Info object will convert permissions from a list of strings in to a Permissions objects.

FS URLs

PyFilesystem can open a filesystem via an FS URL, which is similar to a URL you might enter in to a browser. FS URLs are useful if you want to specify a filesystem dynamically, such as in a conf file or from the command line.

Format

FS URLs are formatted in the following way:

<protocol>://<username>:<password>@<resource>

The components are as follows:

  • <protocol> Identifies the type of filesystem to create. e.g. osfs, ftp.
  • <username> Optional username.
  • <password> Optional password.
  • <resource> A resource, which may be a domain, path, or both.

Here are a few examples:

osfs://~/projects
osfs://c://system32
ftp://ftp.example.org/pub
mem://
ftp://will:daffodil@ftp.example.org/private

If <type> is not specified then it is assumed to be an OSFS, i.e. the following FS URLs are equivalent:

osfs://~/projects
~/projects

Note

The username and passwords fields may not contain a colon (:) or an @ symbol. If you need these symbols they may be percent encoded.

URL Parameters

FS URLs may also be appended with a ? symbol followed by a url-encoded query string. For example:

myprotocol://example.org?key1=value1&key2

The query string would be decoded as {"key1": "value1", "key2": ""}.

Query strings are used to provide additional filesystem-specific information used when opening. See the filesystem documentation for information on what query string parameters are supported.

Opening FS URLS

To open a filesysem with a FS URL, you can use open_fs(), which may be imported and used as follows:

from fs import open_fs
projects_fs = open_fs('osfs://~/projects')

Walking

Walking a filesystem means recursively visiting a directory and any sub-directories. It is a fairly common requirement for copying, searching etc.

To walk a filesystem (or directory) you can construct a Walker object and use its methods to do the walking. Here’s an example that prints the path to every Python file in your projects directory:

>>> from fs import open_fs
>>> from fs.walk import Walker
>>> home_fs = open_fs('~/projects')
>>> walker = Walker(filter=['*.py'])
>>> for path in walker.files(home_fs):
...     print(path)

Generally speaking, however, you will only need to construct a Walker object if you want to customize some behavior of the walking algorithm. This is because you can access the functionality of a Walker object via the walk attribute on FS objects. Here’s an example:

>>> from fs import open_fs
>>> home_fs = open_fs('~/projects')
>>> for path in home_fs.walk.files(filter=['*.py']):
...     print(path)

Note that the files method above doesn’t require a fs parameter. This is because the walk attribute is a property which returns a BoundWalker object, which associates the filesystem with a walker.

Walk Methods

If you call the walk attribute on a BoundWalker it will return an iterable of Step named tuples with three values; a path to the directory, a list of Info objects for directories, and a list of Info objects for the files. Here’s an example:

for step in home_fs.walk(filter=['*.py']):
    print('In dir {}'.format(step.path))
    print('sub-directories: {!r}'.format(step.dirs))
    print('files: {!r}'.format(step.files))

Note

Methods of BoundWalker invoke a corresponding method on a Walker object, with the bound filesystem.

The walk attribute may appear to be a method, but is in fact a callable object. It supports other convenient methods that supply different information from the walk. For instance, files(), which returns an iterable of file paths. Here’s an example:

for path in home_fs.walk.files(filter=['*.py']):
    print('Python file: {}'.format(path))

The compliment to files is dirs() which returns paths to just the directories (and ignoring the files). Here’s an example:

for dir_path in home_fs.walk.dirs():
    print("{!r} contains sub-directory {}".format(home_fs, dir_path))

The info() method returns a generator of tuples containing a path and an Info object. You can use the is_dir attribute to know if the path refers to a directory or file. Here’s an example:

for path, info in home_fs.walk.info():
    if info.is_dir:
        print("[dir] {}".format(path))
    else:
        print("[file] {}".format(path))

Finally, here’s a nice example that counts the number of bytes of Python code in your home directory:

bytes_of_python = sum(
    info.size
    for info in home_fs.walk.info(namespaces=['details'])
    if not info.is_dir
)

Search Algorithms

There are two general algorithms for searching a directory tree. The first method is "breadth", which yields resources in the top of the directory tree first, before moving on to sub-directories. The second is "depth" which yields the most deeply nested resources, and works backwards to the top-most directory.

Generally speaking, you will only need the a depth search if you will be deleting resources as you walk through them. The default breadth search is a generally more efficient way of looking through a filesystem. You can specify which method you want with the search parameter on most Walker methods.

Builtin Filesystems

App Filesystems

Manage filesystems in platform-specific application directories.

These classes abstract away the different requirements for user data across platforms, which vary in their conventions. They are all subclasses of OSFS.

class fs.appfs.UserDataFS(appname, author=None, version=None, roaming=False, create=True)

A filesystem for per-user application data.

May also be opened with open_fs('userdata://appname:author:version').

Parameters:
  • appname (str) – The name of the application.
  • author (str) – The name of the author (used on Windows).
  • version (str) – Optional version string, if a unique location per version of the application is required.
  • roaming (bool) – If True, use a roaming profile on Windows.
  • create (bool) – If True (the default) the directory will be created if it does not exist.
class fs.appfs.UserConfigFS(appname, author=None, version=None, roaming=False, create=True)

A filesystem for per-user config data.

May also be opened with open_fs('userconf://appname:author:version').

Parameters:
  • appname (str) – The name of the application.
  • author (str) – The name of the author (used on Windows).
  • version (str) – Optional version string, if a unique location per version of the application is required.
  • roaming (bool) – If True, use a roaming profile on Windows.
  • create (bool) – If True (the default) the directory will be created if it does not exist.
class fs.appfs.SiteDataFS(appname, author=None, version=None, roaming=False, create=True)

A filesystem for application site data.

May also be opened with open_fs('sitedata://appname:author:version').

Parameters:
  • appname (str) – The name of the application.
  • author (str) – The name of the author (used on Windows).
  • version (str) – Optional version string, if a unique location per version of the application is required.
  • roaming (bool) – If True, use a roaming profile on Windows.
  • create (bool) – If True (the default) the directory will be created if it does not exist.
class fs.appfs.SiteConfigFS(appname, author=None, version=None, roaming=False, create=True)

A filesystem for application config data.

May also be opened with open_fs('siteconf://appname:author:version').

Parameters:
  • appname (str) – The name of the application.
  • author (str) – The name of the author (used on Windows).
  • version (str) – Optional version string, if a unique location per version of the application is required.
  • roaming (bool) – If True, use a roaming profile on Windows.
  • create (bool) – If True (the default) the directory will be created if it does not exist.
class fs.appfs.UserCacheFS(appname, author=None, version=None, roaming=False, create=True)

A filesystem for per-user application cache data.

May also be opened with open_fs('usercache://appname:author:version').

Parameters:
  • appname (str) – The name of the application.
  • author (str) – The name of the author (used on Windows).
  • version (str) – Optional version string, if a unique location per version of the application is required.
  • roaming (bool) – If True, use a roaming profile on Windows.
  • create (bool) – If True (the default) the directory will be created if it does not exist.
class fs.appfs.UserLogFS(appname, author=None, version=None, roaming=False, create=True)

A filesystem for per-user application log data.

May also be opened with open_fs('userlog://appname:author:version').

Parameters:
  • appname (str) – The name of the application.
  • author (str) – The name of the author (used on Windows).
  • version (str) – Optional version string, if a unique location per version of the application is required.
  • roaming (bool) – If True, use a roaming profile on Windows.
  • create (bool) – If True (the default) the directory will be created if it does not exist.

FTP Filesystem

Manage filesystems on remote FTP servers.

class fs.ftpfs.FTPFS(host, user=u'anonymous', passwd=u'', acct=u'', timeout=10, port=21, proxy=None)

A FTP (File Transport Protocol) Filesystem.

Parameters:
  • host (str) – A FTP host, e.g. 'ftp.mirror.nl'.
  • user (str, optional) – A username (default is 'anonymous').
  • passwd (str, optional) – Password for the server, or None for anon.
  • acct (str, optional) – FTP account.
  • timeout (int, optional) – Timeout for contacting server (in seconds, defaults to 10).
  • port (int, optional) – FTP port number (default 21).
  • proxy (str) – An FTP proxy, or None (default) for no proxy.
features

dict – features of the remote FTP server.

ftp

FTP – the underlying FTP client.

ftp_url

Get the FTP url this filesystem will open.

supports_mlst

Check if server supports MLST feature.

Memory Filesystem

Manage a volatile in-memory filesystem.

class fs.memoryfs.MemoryFS

A filesystem that stored in memory.

Memory filesystems are useful for caches, temporary data stores, unit testing, etc. Since all the data is in memory, they are very fast, but non-permanent. The MemoryFS constructor takes no arguments.

Example

>>> mem_fs = MemoryFS()
Or via an FS URL:
>>> import fs
>>> mem_fs = fs.open_fs('mem://')

Mount Filesystem

A Mount FS is a virtual filesystem which can seamlessly map sub-directories on to other filesystems.

For example, lets say we have two filesystems containing config files and resources respectively:

[config_fs]
|-- config.cfg
`-- defaults.cfg

[resources_fs]
|-- images
|   |-- logo.jpg
|   `-- photo.jpg
`-- data.dat

We can combine these filesystems in to a single filesystem with the following code:

from fs.mountfs import MountFS
combined_fs = MountFS()
combined_fs.mount('config', config_fs)
combined_fs.mount('resources', resources_fs)

This will create a filesystem where paths under config/ map to config_fs, and paths under resources/ map to resources_fs:

[combined_fs]
|-- config
|   |-- config.cfg
|   `-- defaults.cfg
`-- resources
    |-- images
    |   |-- logo.jpg
    |   `-- photo.jpg
    `-- data.dat

Now both filesystems may be accessed with the same path structure:

print(combined_fs.gettext('/config/defaults.cfg'))
read_jpg(combined_fs.open('/resources/images/logo.jpg', 'rb')
class fs.mountfs.MountFS(auto_close=True)

A virtual filesystem that maps directories on to other file-systems.

Parameters:auto_close (bool, optional) – If True (the default), the child filesystems will be closed when MountFS is closed.
mount(path, fs)

Mounts a host FS object on a given path.

Parameters:
  • path (str) – A path within the MountFS.
  • fs (FS or str) – A filesystem (instance or URL) to mount.
exception fs.mountfs.MountError

Bases: exceptions.Exception

Thrown when mounts conflict.

Multi Filesystem

A MultiFS is a filesystem composed of a sequence of other filesystems, where the directory structure of each overlays the previous filesystem in the sequence.

One use for such a filesystem would be to selectively override a set of files, to customize behavior. For example, to create a filesystem that could be used to theme a web application. We start with the following directories:

`-- templates
    |-- snippets
    |   `-- panel.html
    |-- index.html
    |-- profile.html
    `-- base.html

`-- theme
    |-- snippets
    |   |-- widget.html
    |   `-- extra.html
    |-- index.html
    `-- theme.html

And we want to create a single filesystem that will load a file from templates/ only if it isn’t found in theme/. Here’s how we could do that:

from fs.osfs import OSFS
from fs.multifs import MultiFS

theme_fs = MultiFS()
theme_fs.add_fs('templates', OSFS('templates'))
theme_fs.add_fs('theme', OSFS('theme'))

Now we have a theme_fs filesystem that presents a single view of both directories:

|-- snippets
|   |-- panel.html
|   |-- widget.html
|   `-- extra.html
|-- index.html
|-- profile.html
|-- base.html
`-- theme.html
class fs.multifs.MultiFS(auto_close=True)

A filesystem that delegates to a sequence of other filesystems.

Operations on the MultiFS will try each ‘child’ filesystem in order, until it succeeds. In effect, creating a filesystem that combines the files and dirs of its children.

add_fs(name, fs, write=False, priority=0)

Add a filesystem to the MultiFS.

Parameters:
  • name (str) – A unique name to refer to the filesystem being added.
  • fs (FS or str) – The filesystem (instance or URL) to add.
  • write (bool, optional) – If this value is True, then the fs will be used as the writeable FS (defaults to False).
  • priority (int, optional) – An integer that denotes the priority of the filesystem being added. Filesystems will be searched in descending priority order and then by the reverse order they were added. So by default, the most recently added filesystem will be looked at first.
get_fs(name)

Get a filesystem from its name.

Parameters:name (str) – The name of a filesystem previously added.
Returns:the filesystem added as name previously.
Return type:FS
Raises:KeyError – If no filesystem with given name could be found.
iterate_fs()

Get iterator that returns (name, fs) in priority order.

which(path, mode=u'r')

Get a tuple of (name, fs) that the given path would map to.

Parameters:
  • path (str) – A path on the filesystem.
  • mode (str) – An io.open mode.

OS Filesystem

Manage the filesystem provided by your OS.

In essence, an OSFS is a thin layer over the io and os modules of the Python standard library.

class fs.osfs.OSFS(root_path, create=False, create_mode=511)

Create an OSFS.

Parameters:
  • root_path (str or PathLike) – An OS path or path-like object to the location on your HD you wish to manage.
  • create (bool, optional) – Set to True to create the root directory if it does not already exist, otherwise the directory should exist prior to creating the OSFS instance (default False).
  • create_mode (int, optional) – The permissions that will be used to create the directory if create is True and the path doesn’t exist, defaults to 0o777.
Raises:

fs.errors.CreateFailed – If root_path does not exist, or could not be created.

Examples

>>> current_directory_fs = OSFS('.')
>>> home_fs = OSFS('~/')
>>> windows_system32_fs = OSFS('c://system32')

Sub Filesystem

Manage a directory in a parent filesystem.

class fs.subfs.ClosingSubFS(parent_fs, path)

A version of SubFS which closes its parent when closed.

class fs.subfs.SubFS(parent_fs, path)

A sub-directory on another filesystem.

A SubFS is a filesystem object that maps to a sub-directory of another filesystem. This is the object that is returned by opendir.

Tar Filesystem

Manage the filesystem in a Tar archive.

class fs.tarfs.TarFS(wrap_fs)

Read and write tar files.

There are two ways to open a TarFS for the use cases of reading a tar file, and creating a new one.

If you open the TarFS with write set to False (the default), then the filesystem will be a read only filesystem which maps to the files and directories within the tar file. Files are decompressed on the fly when you open them.

Here’s how you might extract and print a readme from a tar file:

with TarFS('foo.tar.gz') as tar_fs:
    readme = tar_fs.gettext('readme.txt')

If you open the TarFS with write set to True, then the TarFS will be a empty temporary filesystem. Any files / directories you create in the TarFS will be written in to a tar file when the TarFS is closed. The compression is set from the new file name but may be set manually with the compression argument.

Here’s how you might write a new tar file containing a readme.txt file:

with TarFS('foo.tar.xz', write=True) as new_tar:
    new_tar.settext(
        'readme.txt',
        'This tar file was written by PyFilesystem'
    )
Parameters:
  • file (str or io.IOBase) – An OS filename, or an open file handle.
  • write (bool, optional) – Set to True to write a new tar file, or use default (False) to read an existing tar file.
  • compression (str, optional) – Compression to use (one of the formats supported by tarfile: xz, gz, bz2, or None).
  • temp_fs (str, optional) – An FS URL for the temporary filesystem used to store data prior to tarring.
class fs.tarfs.WriteTarFS(file, compression=None, encoding=u'utf-8', temp_fs=u'temp://__tartemp__')

A writable tar file.

write_tar(file=None, compression=None, encoding=None)

Write tar to a file.

Parameters:
  • file (str or io.IOBase, optional) – Destination file, may be a file name or an open file object.
  • compression (str, optional) – Compression to use (one of the constants defined in tarfile in the stdlib).
  • encoding (str, optional) – The character encoding to use (default uses the encoding defined in __init__).

Note

This is called automatically when the TarFS is closed.

class fs.tarfs.ReadTarFS(**kwargs)

A readable tar file.

Temporary Filesystem

Manage filesystems in temporary locations.

A temporary filesytem is stored in a location defined by your OS (/tmp on linux). The contents are deleted when the filesystem is closed.

A TempFS is a good way of preparing a directory structure in advance, that you can later copy. It can also be used as a temporary data store.

class fs.tempfs.TempFS(identifier=None, temp_dir=None, auto_clean=True, ignore_clean_errors=True)

A temporary filesystem on the OS.

Parameters:
  • identifier (str) – A string to distinguish the directory within the OS temp location, used as part of the directory name.
  • temp_dir (str, optional) – An OS path to your temp directory (leave as None to auto-detect)
  • auto_clean (bool, optional) – If True (the default), the directory contents will be wiped on close.
  • ignore_clean_errors (bool, optional) – If True (the default), any errors in the clean process will be raised. If False, they will be suppressed.
clean()

Clean (delete) temporary files created by this filesystem.

Zip Filesystem

Manage the filesystem in a Zip archive.

class fs.zipfs.ReadZipFS(**kwargs)

A readable zip file.

class fs.zipfs.WriteZipFS(file, compression=8, encoding=u'utf-8', temp_fs=u'temp://__ziptemp__')

A writable zip file.

write_zip(file=None, compression=None, encoding=None)

Write zip to a file.

Parameters:
  • file (str or io.IOBase, optional) – Destination file, may be a file name or an open file handle.
  • compression (str, optional) – Compression to use (one of the constants defined in the zipfile module in the stdlib).
  • encoding (str, optional) – The character encoding to use (default uses the encoding defined in __init__).

Note

This is called automatically when the ZipFS is closed.

class fs.zipfs.ZipFS(wrap_fs)

Read and write zip files.

There are two ways to open a ZipFS for the use cases of reading a zip file, and creating a new one.

If you open the ZipFS with write set to False (the default) then the filesystem will be a read only filesystem which maps to the files and directories within the zip file. Files are decompressed on the fly when you open them.

Here’s how you might extract and print a readme from a zip file:

with ZipFS('foo.zip') as zip_fs:
    readme = zip_fs.gettext('readme.txt')

If you open the ZipFS with write set to True, then the ZipFS will be a empty temporary filesystem. Any files / directories you create in the ZipFS will be written in to a zip file when the ZipFS is closed.

Here’s how you might write a new zip file containing a readme.txt file:

with ZipFS('foo.zip', write=True) as new_zip:
    new_zip.settext(
        'readme.txt',
        'This zip file was written by PyFilesystem'
    )
Parameters:
  • file (str or io.IOBase) – An OS filename, or an open file object.
  • write (bool, optional) – Set to True to write a new zip file, or False (default) to read an existing zip file.
  • compression (str, optional) – Compression to use (one of the constants defined in the zipfile module in the stdlib).
  • temp_fs (str, optional) – An FS URL for the temporary filesystem used to store data prior to zipping.

Implementing Filesystems

With a little care, you can implement a PyFilesystem interface for any filesystem, which will allow it to work interchangeably with any of the built-in FS classes and tools.

To create a PyFilesystem interface, derive a class from FS and implement the Essential Methods. This should give you a working FS class.

Take care to copy the method signatures exactly, including default values. It is also essential that you follow the same logic with regards to exceptions, and only raise exceptions in errors.

Constructor

There are no particular requirements regarding how a PyFilesystem class is constructed, but be sure to call the base class __init__ method with no parameters.

Thread Safety

All Filesystems should be thread-safe. The simplest way to achieve that is by using the _lock attribute supplied by the FS constructor. This is a RLock object from the standard library, which you can use as a context manager, so methods you implement will start something like this:

with self._lock:
    do_something()

You aren’t required to use _lock. Just as long as calling methods on the FS object from multiple threads doesn’t break anything.

Python Versions

PyFilesystem supports Python2.7 and Python3.X. The differences between the two major Python versions are largely managed by the six library.

You aren’t obligated to support the same versions of Python that PyFilesystem itself supports, but it is recommended if your project is for general use.

Testing Filesystems

To test your implementation, you can borrow the test suite used to test the built in filesystems. If your code passes these tests, then you can be confident your implementation will work seamlessly.

Here’s the simplest possible example to test a filesystem class called MyFS:

from fs.test import FSTestCases

class TestMyFS(FSTestCases):

    def make_fs(self):
        # Return an instance of your FS object here
        return MyFS()

You may also want to override some of the methods in the test suite for more targeted testing:

class fs.test.FSTestCases

Basic FS tests.

assert_bytes(path, contents)

Assert a file contains the given bytes.

Parameters:
  • path (str) – A path on the filesystem.
  • contents (bytes) – Bytes to compare.
assert_exists(path)

Assert a path exists.

Parameters:path (str) – A path on the filesystem.
assert_isdir(path)

Assert a path is a directory.

Parameters:path (str) – A path on the filesystem.
assert_isfile(path)

Assert a path is a file.

Parameters:path (str) – A path on the filesystem.
assert_not_exists(path)

Assert a path does not exist.

Parameters:path (str) – A path on the filesystem.
assert_text(path, contents)

Assert a file contains the given text.

Parameters:
  • path (str) – A path on the filesystem.
  • contents (str) – Text to compare.
destroy_fs(fs)

Destroy a FS instance.

Parameters:fs (FS) – A filesystem instance previously opened by make_fs.
make_fs()

Return an FS instance.

test_geturl_purpose()

Check an unknown purpose raises a NoURL error.

test_validatepath()

Check validatepath returns an absolute path.

Essential Methods

The following methods MUST be implemented in a PyFilesystem interface.

Non - Essential Methods

The following methods MAY be implemented in a PyFilesystem interface.

These methods have a default implementation in the base class, but may be overridden if you can supply a more optimal version.

Exactly which methods you should implement depends on how and where the data is stored. For network filesystems, a good candidate to implement, is the scandir method which would otherwise call a combination of listdir and getinfo for each file.

In the general case, it is a good idea to look at how these methods are implemented in FS, and only write a custom version if it would be more efficient than the default.

Helper Methods

These methods SHOULD NOT be implemented.

Implementing these is highly unlikely to be worthwhile.

Creating an extension

Once a filesystem has been implemented, it can be integrated with other applications and projects using PyFilesystem.

Naming Convention

For visibility in PyPi, we recommend that your package be prefixed with fs-. For instance if you have implemented an AwesomeFS PyFilesystem class, your packaged could be be named fs-awesome or fs-awesomefs.

Opener

In order for your filesystem to be opened with an FS URL you should define an Opener class.

Here’s an example taken from an Amazon S3 Filesystem:

"""Defines the S3FSOpener."""

__all__ = ['S3FSOpener']

from fs.opener import Opener, OpenerError

from ._s3fs import S3FS


class S3FSOpener(Opener):
    protocols = ['s3']

    def open_fs(self, fs_url, parse_result, writeable, create, cwd):
        bucket_name, _, dir_path = parse_result.resource.partition('/')
        if not bucket_name:
            raise OpenerError(
                "invalid bucket name in '{}'".format(fs_url)
            )
        s3fs = S3FS(
            bucket_name,
            dir_path=dir_path or '/',
            aws_access_key_id=parse_result.username or None,
            aws_secret_access_key=parse_result.password or None,
        )
        return s3fs

By convention this would be defined in opener.py.

To register the opener you will need to define an entry point in your setup.py. See below for an example.

The setup.py file

Refer to the setuptools documentation to see how to write a setup.py file. There are only a few things that should be kept in mind when creating a Pyfilesystem2 extension. Make sure that:

  • fs is in the install_requires list. You should reference the version number with the ~= operator which ensures that the install will get any bugfix releases of PyFilesystem but not any potentially breaking changes.
  • Ìf you created an opener, include it as an fs.opener entry point, using the name of the entry point as the protocol to be used.

Here is an minimal setup.py for our project:

from setuptools import setup
setup(
    name='fs-awesomefs',  # Name in PyPi
    author="You !",
    author_email="your.email@domain.ext",
    description="An awesome filesystem for pyfilesystem2 !",
    install_requires=[
        "fs~=2.0.5"
    ],
    entry_points = {
        'fs.opener': [
            'awe = awesomefs.opener:AwesomeFSOpener',
        ]
    },
    license="MY LICENSE",
    packages=['awesomefs'],
    version="X.Y.Z",
)

Good Practices

Keep track of your achievements! Add the following values to your __init__.py:

  • __version__ The version of the extension (we recommend following Semantic Versioning),
  • __author__ Your name(s).
  • __author_email__ Your email(s).
  • __license__ The module’s license.

Let us Know

Contact us to add your filesystem to the PyFilesystem Wiki.

Live Example

See fs.sshfs for a functioning PyFilesystem2 extension implementing a Pyfilesystem2 filesystem over SSH.

External Filesystems

See the following wiki page for a list of filesystems not in the core library, and community contributed filesystems.

https://www.pyfilesystem.org/page/index-of-filesystems/

If you have developed a filesystem that you would like added to the above page, please let us know by opening a Github issue.

Reference

fs.base

PyFilesystem base class.

The filesystem base class is common to all filesystems. If you familiarize yourself with this (rather straightforward) API, you can work with any of the supported filesystems.

class fs.base.FS

Base class for FS objects.

appendbytes(path, data)

Append bytes to the end of a file, creating it if needed.

Parameters:
  • path (str) – Path to a file.
  • data (bytes) – Bytes to append.
Raises:
appendtext(path, text, encoding=u'utf-8', errors=None, newline=u'')

Append text to the end of a file, creating it if needed.

Parameters:
  • path (str) – Path to a file.
  • text (str) – Text to append.
  • encoding (str, optional) – Encoding for text files (defaults to utf-8).
  • errors (str, optional) – What to do with unicode decode errors (see codecs module for more information).
  • newline (str, optional) – Newline parameter.
Raises:
check()

Check if a filesystem may be used.

Raises:fs.errors.FilesystemClosed – if the filesystem is closed.
close()

Close the filesystem and release any resources.

It is important to call this method when you have finished working with the filesystem. Some filesystems may not finalize changes until they are closed (archives for example). You may call this method explicitly (it is safe to call close multiple times), or you can use the filesystem as a context manager to automatically close.

Example

>>> with OSFS('~/Desktop') as desktop_fs:
...    desktop_fs.settext(
...        'note.txt',
...        "Don't forget to tape Game of Thrones"
...    )

If you attempt to use a filesystem that has been closed, a FilesystemClosed exception will be thrown.

copy(src_path, dst_path, overwrite=False)

Copy file contents from src_path to dst_path.

Parameters:
  • src_path (str) – Path of source file.
  • dst_path (str) – Path to destination file.
  • overwrite (bool, Optional) – If True, overwrite the destination file if it exists (defaults to False).
Raises:
copydir(src_path, dst_path, create=False)

Copy the contents of src_path to dst_path.

Parameters:
  • src_path (str) – Path of source directory.
  • dst_path (str) – Path to destination directory.
  • create (bool, optional) – If True, then dst_path will be created if it doesn’t exist alreadys (defaults to False).
Raises:

fs.errors.ResourceNotFound – If the dst_path does not exist, and create is not True.

create(path, wipe=False)

Create an empty file.

The default behavior is to create a new file if one doesn’t already exist. If wipe is True, any existing file will be truncated.

Parameters:
  • path (str) – Path to a new file in the filesystem.
  • wipe (bool, optional) – If True, truncate any existing file to 0 bytes (defaults to False).
Returns:

True if a new file had to be created.

Return type:

bool

desc(path)

Return a short descriptive text regarding a path.

Parameters:path (str) – A path to a resource on the filesystem.
Returns:a short description of the path.
Return type:str
exists(path)

Check if a path maps to a resource.

Parameters:path (str) – Path to a resource.
Returns:True if a resource exists at the given path.
Return type:bool
filterdir(path, files=None, dirs=None, exclude_dirs=None, exclude_files=None, namespaces=None, page=None)

Get an iterator of resource info, filtered by patterns.

This method enhances scandir with additional filtering functionality.

Parameters:
  • path (str) – A path to a directory on the filesystem.
  • files (list, optional) – A list of UNIX shell-style patterns to filter file names, e.g. ['*.py'].
  • dirs (list, optional) – A list of UNIX shell-style patterns to filter directory names.
  • exclude_dirs (list, optional) – An optional list of patterns used to exclude directories.
  • exclude_files (list, optional) – An optional list of patterns used to exclude files.
  • namespaces (list, optional) – A list of namespaces to include in the resource information, e.g. ['basic', 'access'].
  • page (tuple, optional) – May be a tuple of (<start>, <end>) indexes to return an iterator of a subset of the resource info, or None to iterate over the entire directory. Paging a directory scan may be necessary for very large directories.
Returns:

an iterator of Info objects.

Return type:

Iterator

getbasic(path)

Get the basic resource info.

This method is shorthand for the following:

fs.getinfo(path, namespaces=['basic'])
Parameters:path (str) – A path on the filesystem.
Returns:Resource information object for path.
Return type:Info
getbytes(path)

Get the contents of a file as bytes.

Parameters:path (str) – A path to a readable file on the filesystem.
Returns:the file contents.
Return type:bytes
Raises:fs.errors.ResourceNotFound – if path does not exist.
getdetails(path)

Get the details resource info.

This method is shorthand for the following:

fs.getinfo(path, namespaces=['details'])
Parameters:path (str) – A path on the filesystem.
Returns:Resource information object for path.
Return type:Info
getfile(path, file, chunk_size=None, **options)

Copies a file from the filesystem to a file-like object.

This may be more efficient that opening and copying files manually if the filesystem supplies an optimized method.

Parameters:
  • path (str) – Path to a resource.
  • file (file-like) – A file-like object open for writing in binary mode.
  • chunk_size (int, optional) – Number of bytes to read at a time, if a simple copy is used, or None to use sensible default.
  • **options – Implementation specific options required to open the source file.

Note that the file object file will not be closed by this method. Take care to close it after this method completes (ideally with a context manager).

Example

>>> with open('starwars.mov', 'wb') as write_file:
...     my_fs.getfile('/movies/starwars.mov', write_file)
getinfo(path, namespaces=None)

Get information about a resource on a filesystem.

Parameters:
  • path (str) – A path to a resource on the filesystem.
  • namespaces (list, optional) – Info namespaces to query (defaults to basic).
Returns:

resource information object.

Return type:

Info

For more information regarding resource information, see Resource Info.

getmeta(namespace=u'standard')

Get meta information regarding a filesystem.

Parameters:namespace (str, optional) – The meta namespace (defaults to "standard").
Returns:the meta information.
Return type:dict

Meta information is associated with a namespace which may be specified with the namespace parameter. The default namespace, "standard", contains common information regarding the filesystem’s capabilities. Some filesystems may provide other namespaces which expose less common or implementation specific information. If a requested namespace is not supported by a filesystem, then an empty dictionary will be returned.

The "standard" namespace supports the following keys:

key Description
case_insensitive True if this filesystem is case insensitive.
invalid_path_chars A string containing the characters that may not be used on this filesystem.
max_path_length Maximum number of characters permitted in a path, or None for no limit.
max_sys_path_length Maximum number of characters permitted in a sys path, or None for no limit.
network True if this filesystem requires a network.
read_only True if this filesystem is read only.
supports_rename True if this filesystem supports an os.rename operation.

Most builtin filesystems will provide all these keys, and third- party filesystems should do so whenever possible, but a key may not be present if there is no way to know the value.

Note

Meta information is constant for the lifetime of the filesystem, and may be cached.

getsize(path)

Get the size (in bytes) of a resource.

Parameters:path (str) – A path to a resource.
Returns:the size of the resource.
Return type:int

The size of a file is the total number of readable bytes, which may not reflect the exact number of bytes of reserved disk space (or other storage medium).

The size of a directory is the number of bytes of overhead use to store the directory entry.

getsyspath(path)

Get the system path of a resource.

Parameters:path (str) – A path on the filesystem.
Returns:the system path of the resource, if any.
Return type:str
Raises:fs.errors.NoSysPath – If there is no corresponding system path.

A system path is one recognized by the OS, that may be used outside of PyFilesystem (in an application or a shell for example). This method will get the corresponding system path that would be referenced by path.

Not all filesystems have associated system paths. Network and memory based filesystems, for example, may not physically store data anywhere the OS knows about. It is also possible for some paths to have a system path, whereas others don’t.

If path doesn’t have a system path, a NoSysPath exception will be thrown.

Note

A filesystem may return a system path even if no resource is referenced by that path – as long as it can be certain what that system path would be.

gettext(path, encoding=None, errors=None, newline=u'')

Get the contents of a file as a string.

Parameters:
  • path (str) – A path to a readable file on the filesystem.
  • encoding (str, optional) – Encoding to use when reading contents in text mode (defaults to None, reading in binary mode).
  • errors (str, optional) – Unicode errors parameter.
  • newline (str, optional) – Newlines parameter.
Returns:

file contents.

Return type:

str

Raises:

fs.errors.ResourceNotFound – If path does not exist.

gettype(path)

Get the type of a resource.

Parameters:path (str) – A path on the filesystem.
Returns:the type of the resource.
Return type:ResourceType

A type of a resource is an integer that identifies the what the resource references. The standard type integers may be one of the values in the ResourceType enumerations.

The most common resource types, supported by virtually all filesystems are directory (1) and file (2), but the following types are also possible:

ResourceType value
unknown 0
directory 1
file 2
character 3
block_special_file 4
fifo 5
socket 6
symlink 7

Standard resource types are positive integers, negative values are reserved for implementation specific resource types.

geturl(path, purpose=u'download')

Get the URL to a given resource.

Parameters:
  • path (str) – A path on the filesystem
  • purpose (str, optional) – A short string that indicates which URL to retrieve for the given path (if there is more than one). The default is 'download', which should return a URL that serves the file. Other filesystems may support other values for purpose.
Returns:

a URL.

Return type:

str

Raises:

fs.errors.NoURL – If the path does not map to a URL.

hassyspath(path)

Check if a path maps to a system path.

Parameters:path (str) – A path on the filesystem.
Returns:True if the resource at path has a syspath.
Return type:bool
hasurl(path, purpose=u'download')

Check if a path has a corresponding URL.

Parameters:
  • path (str) – A path on the filesystem.
  • purpose (str, optional) – A purpose parameter, as given in geturl.
Returns:

True if an URL for the given purpose exists.

Return type:

bool

isclosed()

Check if the filesystem is closed.

isdir(path)

Check if a path maps to an existing directory.

Parameters:path (str) – A path on the filesystem.
Returns:True if path maps to a directory.
Return type:bool
isempty(path)

Check if a directory is empty.

A directory is considered empty when it does not contain any file or any directory.

Parameters:

path (str) – A path to a directory on the filesystem.

Returns:

True if the directory is empty.

Return type:

bool

Raises:
  • errors.DirectoryExpected – If path is not a directory.
  • errors.ResourceNotFound – If path does not exist.
isfile(path)

Check if a path maps to an existing file.

Parameters:path (str) – A path on the filesystem.
Returns:True if path maps to a file.
Return type:bool

Check if a path maps to a symlink.

Parameters:path (str) – A path on the filesystem.
Returns:True if path maps to a symlink.
Return type:bool
listdir(path)

Get a list of the resource names in a directory.

This method will return a list of the resources in a directory. A resource is a file, directory, or one of the other types defined in ResourceType.

Parameters:

path (str) – A path to a directory on the filesystem

Returns:

list of names, relative to path.

Return type:

list

Raises:
lock()

Get a context manager that locks the filesystem.

Locking a filesystem gives a thread exclusive access to it. Other threads will block until the threads with the lock has left the context manager.

Returns:a lock specific to the filesystem instance.
Return type:threading.RLock

Example

>>> with my_fs.lock():  # May block
...    # code here has exclusive access to the filesystem

It is a good idea to put a lock around any operations that you would like to be atomic. For instance if you are copying files, and you don’t want another thread to delete or modify anything while the copy is in progress.

Locking with this method is only required for code that calls multiple filesystem methods. Individual methods are thread safe already, and don’t need to be locked.

Note

This only locks at the Python level. There is nothing to prevent other processes from modifying the filesystem outside of the filesystem instance.

makedir(path, permissions=None, recreate=False)

Make a directory.

Parameters:
  • path (str) – Path to directory from root.
  • permissions (Permissions, optional) – a Permissions instance, or None to use default.
  • recreate (bool, optional) – Set to True to avoid raising an error if the directory already exists (defaults to False).
Returns:

a filesystem whose root is the new directory.

Return type:

SubFS

Raises:
makedirs(path, permissions=None, recreate=False)

Make a directory, and any missing intermediate directories.

Parameters:
  • path (str) – Path to directory from root.
  • permissions (Permissions, optional) – Initial permissions, or None to use defaults.
  • recreate (bool, optional) – If False (the default), attempting to create an existing directory will raise an error. Set to True to ignore existing directories.
Returns:

A sub-directory filesystem.

Return type:

SubFS

Raises:
match(patterns, name)

Check if a name matches any of a list of wildcards.

Parameters:
  • patterns (list) – A list of patterns, e.g. ['*.py']
  • name (str) – A file or directory name (not a path)
Returns:

True if name matches any of the patterns.

Return type:

bool

If a filesystem is case insensitive (such as Windows) then this method will perform a case insensitive match (i.e. *.py will match the same names as *.PY). Otherwise the match will be case sensitive (*.py and *.PY will match different names).

Example

>>> home_fs.match(['*.py'], '__init__.py')
True
>>> home_fs.match(['*.jpg', '*.png'], 'foo.gif')
False

Note

If patterns is None (or ['*']), then this method will always return True.

move(src_path, dst_path, overwrite=False)

Move a file from src_path to dst_path.

Parameters:
  • src_path (str) – A path on the filesystem to move.
  • dst_path (str) – A path on the filesystem where the source file will be written to.
  • overwrite (bool, optional) – If True, destination path will be overwritten if it exists.
Raises:
movedir(src_path, dst_path, create=False)

Move contents of directory src_path to dst_path.

Parameters:
  • src_path (str) – Path of source directory on the filesystem.
  • dst_path (str) – Path to destination directory.
  • create (bool, optional) – If True, then dst_path will be created if it doesn’t exist already (defaults to False).
Raises:

fs.errors.ResourceNotFound – if dst_path does not exist, and create is False.

open(path, mode=u'r', buffering=-1, encoding=None, errors=None, newline=u'', **options)

Open a file.

Parameters:
  • path (str) – A path to a file on the filesystem.
  • mode (str, optional) – Mode to open the file object with (defaults to r).
  • buffering (int, optional) – Buffering policy (-1 to use default buffering, 0 to disable buffering, 1 to select line buffering, of any positive integer to indicate a buffer size).
  • encoding (str, optional) – Encoding for text files (defaults to utf-8)
  • errors (str, optional) – What to do with unicode decode errors (see codecs module for more information).
  • newline (str, optional) – Newline parameter.
  • **options – keyword arguments for any additional information required by the filesystem (if any).
Returns:

a file-like object.

Return type:

io.IOBase

Raises:
openbin(path, mode=u'r', buffering=-1, **options)

Open a binary file-like object.

Parameters:
  • path (str) – A path on the filesystem.
  • mode (str, optional) – Mode to open file (must be a valid non-text mode, defaults to r). Since this method only opens binary files, the b in the mode string is implied.s
  • buffering (int, optional) – Buffering policy (-1 to use default buffering, 0 to disable buffering, or any positive integer to indicate a buffer size).
  • **options – keyword arguments for any additional information required by the filesystem (if any).
Returns:

a file-like object.

Return type:

io.IOBase

Raises:
opendir(path, factory=None)

Get a filesystem object for a sub-directory.

Parameters:
  • path (str) – Path to a directory on the filesystem.
  • factory (callable, optional) – A callable that when invoked with an FS instance and path will return a new FS object representing the sub-directory contents. If no factory is supplied then SubFS will be used.
Returns:

A filesystem representing a sub-directory.

Return type:

SubFS

Raises:

fs.errors.DirectoryExpected – If dst_path does not exist or is not a directory.

remove(path)

Remove a file from the filesystem.

Parameters:

path (str) – Path of the file to remove.

Raises:
removedir(path)

Remove a directory from the filesystem.

Parameters:

path (str) – Path of the directory to remove.

Raises:
removetree(dir_path)

Recursively remove the contents of a directory.

This method is similar to removedir, but will remove the contents of the directory if it is not empty.

Parameters:dir_path (str) – Path to a directory on the filesystem.
scandir(path, namespaces=None, page=None)

Get an iterator of resource info.

Parameters:
  • path (str) – A path to a directory on the filesystem.
  • namespaces (list, optional) – A list of namespaces to include in the resource information, e.g. ['basic', 'access'].
  • page (tuple, optional) – May be a tuple of (<start>, <end>) indexes to return an iterator of a subset of the resource info, or None to iterate over the entire directory. Paging a directory scan may be necessary for very large directories.
Returns:

an iterator of Info objects.

Return type:

Iterator

Raises:
setbinfile(path, file)

Set a file to the contents of a binary file object.

This method copies bytes from an open binary file to a file on the filesystem. If the destination exists, it will first be truncated.

Parameters:
  • path (str) – A path on the filesystem.
  • file (io.IOBase) – a file object open for reading in binary mode.

Note that the file object file will not be closed by this method. Take care to close it after this method completes (ideally with a context manager).

Example

>>> with open('myfile.bin') as read_file:
...     my_fs.setbinfile('myfile.bin', read_file)
setbytes(path, contents)

Copy binary data to a file.

Parameters:
  • path (str) – Destination path on the filesystem.
  • contents (bytes) – Data to be written.
Raises:

TypeError – if contents is not bytes.

setfile(path, file, encoding=None, errors=None, newline=None)

Set a file to the contents of a file object.

Parameters:
  • path (str) – A path on the filesystem.
  • file (io.IOBase) – A file object open for reading.
  • encoding (str, optional) – Encoding of destination file, defaults to None for binary.
  • errors (str, optional) – How encoding errors should be treated (same as io.open).
  • newline (str, optional) – Newline parameter (same as io.open).

This method will read the contents of a supplied file object, and write to a file on the filesystem. If the destination exists, it will first be truncated.

If encoding is supplied, the destination will be opened in text mode.

Note that the file object file will not be closed by this method. Take care to close it after this method completes (ideally with a context manager).

Example

>>> with open('myfile.bin') as read_file:
...     my_fs.setfile('myfile.bin', read_file)
setinfo(path, info)

Set info on a resource.

This method is the compliment to getinfo and is used to set info values on a resource.

Parameters:
  • path (str) – Path to a resource on the filesystem.
  • info (dict) – Dictionary of resource info.
Raises:

fs.errors.ResourceNotFound – If path does not exist on the filesystem

The info dict should be in the same format as the raw info returned by getinfo(file).raw.

Example

>>> details_info = {"details": {
...     "modified_time": time.time()
... }}
>>> my_fs.setinfo('file.txt', details_info)
settext(path, contents, encoding=u'utf-8', errors=None, newline=u'')

Create or replace a file with text.

Parameters:
  • contents (str) – A path on the filesystem.
  • encoding (str, optional) – Encoding of destination file (defaults to 'ut-8').
  • errors (str, optional) – How encoding errors should be treated (same as io.open).
  • newline (str, optional) – Newline parameter (same as io.open).
Raises:

TypeError – if contents is not a unicode string.

settimes(path, accessed=None, modified=None)

Set the accessed and modified time on a resource.

Parameters:
  • path – A path to a resource on the filesystem.
  • accessed (datetime, optional) – The accessed time, or None (the default) to use the current time.
  • modified (datetime, optional) – The modified time, or None (the default) to use the same time as the accessed parameter.
touch(path)

Touch a file on the filesystem.

Touching a file means creating a new file if path doesn’t exist, or update accessed and modified times if the path does exist. This method is similar to the linux command of the same name.

Parameters:path (str) – A path to a file on the filesystem.
tree(**kwargs)

Render a tree view of the filesystem to stdout or a file.

The parameters are passed to render().

Keyword Arguments:
 
  • path (str) – The path of the directory to start rendering from (defaults to root folder, i.e. '/').
  • file (io.IOBase) – An open file-like object to render the tree, or None for stdout.
  • encoding (str) – Unicode encoding, or None to auto-detect.
  • max_levels (int) – Maximum number of levels to display, or None for no maximum.
  • with_color (bool) – Enable terminal color output, or None to auto-detect terminal.
  • dirs_first (bool) – Show directories first.
  • exclude (list) – Option list of directory patterns to exclude from the tree render.
  • filter (list) – Optional list of files patterns to match in the tree render.
validatepath(path)

Check if a path is valid, returning a normalized absolute path.

Many filesystems have restrictions on the format of paths they support. This method will check that path is valid on the underlaying storage mechanism and throw a InvalidPath exception if it is not.

Parameters:

path (str) – A path.

Returns:

A normalized, absolute path.

Return type:

str

Raises:
walk

BoundWalker – a walker bound to this filesystem.

walker_class

alias of fs.walk.Walker

fs.compress

Functions to compress the contents of a filesystem.

Currently zip and tar are supported, using the zipfile and tarfile modules from the standard library.

fs.compress.write_tar(src_fs, file, compression=None, encoding=u'utf-8', walker=None)

Write the contents of a filesystem to a tar file.

Parameters:
  • file (str or io.IOBase) – Destination file, may be a file name or an open file object.
  • compression (str, optional) – Compression to use, or None for a plain Tar archive without compression.
  • encoding (str, optional) – The encoding to use for filenames. The default is "utf-8".
  • walker (Walker, optional) – A Walker instance, or None to use default walker. You can use this to specify which files you want to compress.
fs.compress.write_zip(src_fs, file, compression=8, encoding=u'utf-8', walker=None)

Write the contents of a filesystem to a zip file.

Parameters:
  • file (str or io.IOBase) – Destination file, may be a file name or an open file object.
  • compression (str, optional) – Compression to use (one of the constants defined in the zipfile module in the stdlib). Defaults to zipfile.ZIP_DEFLATED.
  • encoding (str, optional) – The encoding to use for filenames. The default is "utf-8", use "CP437" if compatibility with WinZip is desired.
  • walker (Walker, optional) – A Walker instance, or None to use default walker. You can use this to specify which files you want to compress.

fs.copy

Functions for copying resources between filesystem.

fs.copy.copy_dir(src_fs, src_path, dst_fs, dst_path, walker=None, on_copy=None)

Copy a directory from one filesystem to another.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • src_path (str) – Path to a directory on the source filesystem.
  • dst_fs (FS or str) – Destination filesystem (instance or URL).
  • dst_path (str) – Path to a directory on the destination filesystem.
  • walker (Walker, optional) – A walker object that will be used to scan for files in src_fs. Set this if you only want to consider a sub-set of the resources in src_fs.
  • on_copy (callable, optional) – A function callback called after a single file copy is executed. Expected signature is (src_fs, src_path, dst_fs, dst_path).
fs.copy.copy_dir_if_newer(src_fs, src_path, dst_fs, dst_path, walker=None, on_copy=None)

Copy a directory from one filesystem to another, checking times.

If both source and destination files exist, the copy is executed only if the source file is newer than the destination file. In case modification times of source or destination files are not available, copy is always executed.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • src_path (str) – Path to a directory on the source filesystem.
  • dst_fs (FS or str) – Destination filesystem (instance or URL).
  • dst_path (str) – Path to a directory on the destination filesystem.
  • walker (Walker, optional) – A walker object that will be used to scan for files in src_fs. Set this if you only want to consider a sub-set of the resources in src_fs.
  • on_copy (callable, optional) – A function callback called after a single file copy is executed. Expected signature is (src_fs, src_path, dst_fs, dst_path).
fs.copy.copy_file(src_fs, src_path, dst_fs, dst_path)

Copy a file from one filesystem to another.

If the destination exists, and is a file, it will be first truncated.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • src_path (str) – Path to a file on the source filesystem.
  • dst_fs (FS or str) – Destination filesystem (instance or URL).
  • dst_path (str) – Path to a file on the destination filesystem.
fs.copy.copy_file_if_newer(src_fs, src_path, dst_fs, dst_path)

Copy a file from one filesystem to another, checking times.

If the destination exists, and is a file, it will be first truncated. If both source and destination files exist, the copy is executed only if the source file is newer than the destination file. In case modification times of source or destination files are not available, copy is always executed.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • src_path (str) – Path to a file on the source filesystem.
  • dst_fs (FS or str) – Destination filesystem (instance or URL).
  • dst_path (str) – Path to a file on the destination filesystem.
Returns:

True if the file copy was executed, False otherwise.

Return type:

bool

fs.copy.copy_file_internal(src_fs, src_path, dst_fs, dst_path)

Low level copy, that doesn’t call manage_fs or lock.

If the destination exists, and is a file, it will be first truncated.

This method exists to optimize copying in loops. In general you should prefer copy_file.

Parameters:
  • src_fs (FS or str) – Source filesystem.
  • src_path (str) – Path to a file on the source filesystem.
  • dst_fs (FS or str) – Destination filesystem.
  • dst_path (str) – Path to a file on the destination filesystem.
fs.copy.copy_fs(src_fs, dst_fs, walker=None, on_copy=None)

Copy the contents of one filesystem to another.

Parameters:
  • src_fs (FS or str) – Source filesystem (URL or instance).
  • dst_fs (FS or str) – Destination filesystem (URL or instance).
  • walker (Walker, optional) – A walker object that will be used to scan for files in src_fs. Set this if you only want to consider a sub-set of the resources in src_fs.
  • on_copy (callable) – A function callback called after a single file copy is executed. Expected signature is (src_fs, src_path, dst_fs, dst_path).
fs.copy.copy_fs_if_newer(src_fs, dst_fs, walker=None, on_copy=None)

Copy the contents of one filesystem to another, checking times.

If both source and destination files exist, the copy is executed only if the source file is newer than the destination file. In case modification times of source or destination files are not available, copy file is always executed.

Parameters:
  • src_fs (FS or str) – Source filesystem (URL or instance).
  • dst_fs (FS or str) – Destination filesystem (URL or instance).
  • walker (Walker, optional) – A walker object that will be used to scan for files in src_fs. Set this if you only want to consider a sub-set of the resources in src_fs.
  • on_copy (callable) – A function callback called after a single file copy is executed. Expected signature is (src_fs, src_path, dst_fs, dst_path).
fs.copy.copy_structure(src_fs, dst_fs, walker=None)

Copy directories (but not files) from src_fs to dst_fs.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • dst_fs (FS or str) – Destination filesystem (instance or URL).
  • walker (Walker, optional) – A walker object that will be used to scan for files in src_fs. Set this if you only want to consider a sub-set of the resources in src_fs.

fs.enums

Enums used by PyFilesystem.

class fs.enums.ResourceType

Resource Types.

Positive values are reserved, negative values are implementation dependent.

Most filesystems will support only directory(1) and file(2). Other types exist to identify more exotic resource types supported by Linux filesystems.

class fs.enums.Seek

Constants used by io.IOBase.seek.

These match os.SEEK_CUR, os.SEEK_END, and os.SEEK_SET from the standard library.

fs.errors

Exception classes thrown by filesystem operations.

Errors relating to the underlying filesystem are translated in to one of the following exceptions.

All Exception classes are derived from FSError which may be used as a catch-all filesystem exception.

exception fs.errors.CreateFailed(msg=None, exc=None)

Bases: fs.errors.FSError

Filesystem could not be created.

exception fs.errors.DestinationExists(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

Target destination already exists.

exception fs.errors.DirectoryExists(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

Directory already exists.

exception fs.errors.DirectoryExpected(path, exc=None, msg=None)

Bases: fs.errors.ResourceInvalid

Operation only works on directories.

exception fs.errors.DirectoryNotEmpty(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

Attempt to remove a non-empty directory.

exception fs.errors.FileExists(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

File already exists.

exception fs.errors.FileExpected(path, exc=None, msg=None)

Bases: fs.errors.ResourceInvalid

Operation only works on files.

exception fs.errors.FilesystemClosed(msg=None)

Bases: fs.errors.FSError

Attempt to use a closed filesystem.

exception fs.errors.FSError(msg=None)

Bases: exceptions.Exception

Base exception for the fs module.

exception fs.errors.IllegalBackReference(path)

Bases: exceptions.ValueError

Too many backrefs exist in a path.

This error will occur if the back references in a path would be outside of the root. For example, "/foo/../../", contains two back references which would reference a directory above the root.

Note

This exception is a subclass of ValueError as it is not strictly speaking an issue with a filesystem or resource.

exception fs.errors.InsufficientStorage(path=None, exc=None, msg=None)

Bases: fs.errors.OperationFailed

Storage is insufficient for requested operation.

exception fs.errors.InvalidCharsInPath(path, msg=None)

Bases: fs.errors.InvalidPath

Path contains characters that are invalid on this filesystem.

exception fs.errors.InvalidPath(path, msg=None)

Bases: fs.errors.PathError

Path can’t be mapped on to the underlaying filesystem.

exception fs.errors.MissingInfoNamespace(namespace)

Bases: exceptions.AttributeError

An expected namespace is missing.

exception fs.errors.NoSysPath(path, msg=None)

Bases: fs.errors.PathError

The filesystem does not provide sys paths to the resource.

exception fs.errors.NoURL(path, purpose, msg=None)

Bases: fs.errors.PathError

The filesystem does not provide an URL for the resource.

exception fs.errors.OperationFailed(path=None, exc=None, msg=None)

Bases: fs.errors.FSError

A specific operation failed.

exception fs.errors.OperationTimeout(path=None, exc=None, msg=None)

Bases: fs.errors.OperationFailed

Filesystem took too long.

exception fs.errors.PathError(path, msg=None)

Bases: fs.errors.FSError

Base exception for errors to do with a path string.

exception fs.errors.PermissionDenied(path=None, exc=None, msg=None)

Bases: fs.errors.OperationFailed

Not enough permissions.

exception fs.errors.RemoteConnectionError(path=None, exc=None, msg=None)

Bases: fs.errors.OperationFailed

Operations encountered remote connection trouble.

exception fs.errors.RemoveRootError(path=None, exc=None, msg=None)

Bases: fs.errors.OperationFailed

Attempt to remove the root directory.

exception fs.errors.ResourceError(path, exc=None, msg=None)

Bases: fs.errors.FSError

Base exception class for error associated with a specific resource.

exception fs.errors.ResourceInvalid(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

Resource has the wrong type.

exception fs.errors.ResourceLocked(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

Attempt to use a locked resource.

exception fs.errors.ResourceNotFound(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

Required resource not found.

exception fs.errors.ResourceReadOnly(path, exc=None, msg=None)

Bases: fs.errors.ResourceError

Attempting to modify a read-only resource.

exception fs.errors.Unsupported(path=None, exc=None, msg=None)

Bases: fs.errors.OperationFailed

Operation not supported by the filesystem.

fs.info

Container for filesystem resource informations.

class fs.info.Info(raw_info, to_datetime=<function epoch_to_datetime>)

Container for Resource Info.

Resource informations are returned by the following methods:

Parameters:
  • raw_info (dict) – A dict containing resource info.
  • to_datetime (callable, optional) – A callable that converts an epoch time to a datetime object. The default uses epoch_to_datetime().
accessed

datetime – the resource last access time, or None.

Requires the "details" namespace.

Raises:MissingInfoNamespace – if the "details" namespace is not in the Info.
copy(to_datetime=None)

Create a copy of this resource info object.

created

datetime – the resource creation time, or None.

Requires the "details" namespace.

Raises:MissingInfoNamespace – if the "details" namespace is not in the Info.
get(namespace, key, default=None)

Get a raw info value.

Parameters:
  • namespace (str) – A namespace identifier.
  • key (str) – A key within the namespace.
  • default (object, optional) – A default value to return if either the namespace or the key within the namespace is not found.

Example

>>> info.get('access', 'permissions')
['u_r', 'u_w', '_wx']
gid

int – the group id of the resource, or None.

Requires the "access" namespace.

Raises:MissingInfoNamespace – if the "access" namespace is not in the Info.
group

str – the group of the resource owner, or None.

Requires the "access" namespace.

Raises:MissingInfoNamespace – if the "access" namespace is not in the Info.
has_namespace(namespace)

Check if the resource info contains a given namespace.

Parameters:namespace (str) – A namespace identifier.
Returns:True if the namespace was found, False otherwise.
Return type:bool
is_dir

boolTrue if the resource references a directory.

is_file

boolTrue if the resource references a file.

boolTrue if the resource is a symlink.

is_writeable(namespace, key)

Check if a given key in a namespace is writable.

Uses setinfo.

Parameters:
  • namespace (str) – A namespace identifier.
  • key (str) – A key within the namespace.
Returns:

True if the key can be modified, False otherwise.

Return type:

bool

make_path(dir_path)

Make a path by joining dir_path with the resource name.

Parameters:dir_path (str) – A path to a directory.
Returns:A path to the resource.
Return type:str
metadata_changed

datetime – the resource metadata change time, or None.

Requires the "details" namespace.

Raises:MissingInfoNamespace – if the "details" namespace is not in the Info.
modified

datetime – the resource last modification time, or None.

Requires the "details" namespace.

Raises:MissingInfoNamespace – if the "details" namespace is not in the Info.
name

str – the resource name.

permissions

Permissions – the permissions of the resource, or None.

Requires the "access" namespace.

Raises:MissingInfoNamespace – if the "access" namespace is not in the Info.
size

int – the size of the resource, in bytes.

Requires the "details" namespace.

Raises:MissingInfoNamespace – if the "details" namespace is not in the Info.
target

str – the link target (if resource is a symlink), or None.

Requires the "link" namespace.

Raises:MissingInfoNamespace – if the "link" namespace is not in the Info.
type

ResourceType – the type of the resource.

Requires the "details" namespace.

Raises:MissingInfoNamespace – if the ‘details’ namespace is not in the Info.
uid

int – the user id of the resource, or None.

Requires the "access" namespace.

Raises:MissingInfoNamespace – if the "access" namespace is not in the Info.
user

str – the owner of the resource, or None.

Requires the "access" namespace.

Raises:MissingInfoNamespace – if the "access" namespace is not in the Info.

fs.filesize

Functions for reporting filesizes.

The functions declared in this module should cover the different usecases needed to generate a string representation of a file size using several different units. Since there are many standards regarding file size units, three different functions have been implemented.

fs.filesize.traditional(size)

Convert a filesize in to a string (powers of 1024, JDEC prefixes).

In this convention, 1024 B = 1 KB.

This is the format that was used to display the size of DVDs (700 MB meaning actually about 734 003 200 bytes) before standardisation of IEC units among manufacturers, and still used by Windows to report the storage capacity of hard drives (279.4 GB meaning 279.4 × 1024³ bytes).

Parameters:size (int) – A file size.
Returns:A string containing an abbreviated file size and units.
Return type:str

Example

>>> filesize.traditional(30000)
'29.3 KB'
fs.filesize.decimal(size)

Convert a filesize in to a string (powers of 1000, SI prefixes).

In this convention, 1000 B = 1 kB.

This is typically the format used to advertise the storage capacity of USB flash drives and the like (256 MB meaning actually a storage capacity of more than 256 000 000 B), or used by Mac OS X since v10.6 to report file sizes.

Parameters:int (size) – A file size.
Returns:A string containing a abbreviated file size and units.
Return type:str

Example

>>> filesize.decimal(30000)
'30.0 kB'
fs.filesize.binary(size)

Convert a filesize in to a string (powers of 1024, IEC prefixes).

In this convention, 1024 B = 1 KiB.

This is the format that has gained adoption among manufacturers to avoid ambiguity regarding size units, since it explicitly states using a binary base (KiB = kibi bytes = kilo binary bytes). This format is notably being used by the Linux kernel (see man 7 units).

Parameters:int (size) – A file size.
Returns:A string containing a abbreviated file size and units.
Return type:str

Example

>>> filesize.binary(30000)
'29.3 KiB'

fs.mirror

Function for mirroring a filesystem.

Mirroring will create a copy of a source filesystem on a destination filesystem. If there are no files on the destination, then mirroring is simply a straight copy. If there are any files or directories on the destination they may be deleted or modified to match the source.

In order to avoid redundant copying of files, mirror can compare timestamps, and only copy files with a newer modified date. This timestamp comparison is only done if the file sizes are different.

This scheme will work if you have mirrored a directory previously, and you would like to copy any changes. Otherwise you should set the copy_if_newer parameter to False to guarantee an exact copy, at the expense of potentially copying extra files.

fs.mirror.mirror(src_fs, dst_fs, walker=None, copy_if_newer=True)

Mirror files / directories from one filesystem to another.

Mirroring a filesystem will create an exact copy of src_fs on dst_fs, by removing any files / directories on the destination that aren’t on the source, and copying files that aren’t.

Parameters:
  • src_fs (FS or str) – Source filesystem (URL or instance).
  • dst_fs (FS or str) – Destination filesystem (URL or instance).
  • walker (Walker, optional) – An optional walker instance.
  • copy_if_newer (bool, optional) – Only copy newer files (the default).

fs.move

Functions for moving files between filesystems.

fs.move.move_dir(src_fs, src_path, dst_fs, dst_path)

Move a directory from one filesystem to another.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • src_path (str) – Path to a directory on src_fs
  • dst_fs (FS or str) – Destination filesystem (instance or URL).
  • dst_path (str) – Path to a directory on dst_fs
fs.move.move_file(src_fs, src_path, dst_fs, dst_path)

Move a file from one filesystem to another.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • src_path (str) – Path to a file on src_fs.
  • dst_fs (FS or str); Destination filesystem (instance or URL) –
  • dst_path (str) – Path to a file on dst_fs.
fs.move.move_fs(src_fs, dst_fs)

Move the contents of a filesystem to another filesystem.

Parameters:
  • src_fs (FS or str) – Source filesystem (instance or URL).
  • dst_fs (FS or str) – Destination filesystem (instance or URL).

fs.mode

Abstract I/O mode container.

Mode strings are used in in open and openbin.

class fs.mode.Mode(mode)

An abstraction for I/O modes.

A mode object provides properties that can be used to interrogate the mode strings used when opening files.

Parameters:mode (str) – A mode string, as used by io.open.
Raises:ValueError – If the mode string is invalid.

Example

>>> mode = Mode('rb')
>>> mode.reading
True
>>> mode.writing
False
>>> mode.binary
True
>>> mode.text
False
appending

boolTrue if the mode permits appending.

binary

boolTrue if a mode specifies binary.

create

boolTrue if the mode would create a file.

exclusive

boolTrue if the mode require exclusive creation.

reading

boolTrue if the mode permits reading.

text

boolTrue if a mode specifies text.

to_platform()

Get a mode string for the current platform.

Currently, this just removes the ‘x’ on PY2 because PY2 doesn’t support exclusive mode.

to_platform_bin()

Get a binary mode string for the current platform.

Currently, this just removes the ‘x’ on PY2 because PY2 doesn’t support exclusive mode.

truncate

boolTrue if the mode would truncate an existing file.

updating

boolTrue if the mode permits both reading and writing.

validate(_valid_chars=frozenset([u'a', u'b', u'+', u'r', u't', u'w', u'x']))

Validate the mode string.

Raises:ValueError – if the mode contains invalid chars.
validate_bin()

Validate a mode for opening a binary file.

Raises:ValueError – if the mode contains invalid chars.
writing

boolTrue if the mode permits writing.

fs.mode.check_readable(mode)

Check a mode string allows reading.

Parameters:mode (str) – A mode string, e.g. "rt"
Returns:True if the mode allows reading.
Return type:bool
fs.mode.check_writable(mode)

Check a mode string allows writing.

Parameters:mode (str) – A mode string, e.g. "wt"
Returns:True if the mode allows writing.
Return type:bool
fs.mode.validate_open_mode(mode)

Check mode parameter of open is valid.

Parameters:mode (str) – Mode parameter.
Raises:ValueError if mode is not valid.
fs.mode.validate_openbin_mode(mode, _valid_chars=frozenset([u'a', u'b', u'+', u'r', u'w', u'x']))

Check mode parameter of openbin is valid.

Parameters:mode (str) – Mode parameter.
Raises:ValueError if mode is not valid.

fs.opener

Open filesystems from a URL.

fs.opener.base

Opener abstract base class.

class fs.opener.base.Opener

The base class for filesystem openers.

An opener is responsible for opening a filesystem for a given protocol.

open_fs(fs_url, parse_result, writeable, create, cwd)

Open a filesystem object from a FS URL.

Parameters:
  • fs_url (str) – A filesystem URL.
  • parse_result (ParseResult) – A parsed filesystem URL.
  • writeable (bool) – True if the filesystem must be writable.
  • create (bool) – True if the filesystem should be created if it does not exist.
  • cwd (str) – The current working directory (generally only relevant for OS filesystems).
Raises:

fs.opener.errors.OpenerError – If a filesystem could not be opened for any reason.

Returns:

A filesystem instance.

Return type:

FS

fs.opener.parse

Function to parse FS URLs in to their constituent parts.

class fs.opener.parse.ParseResult

A named tuple containing fields of a parsed FS URL.

protocol

str – The protocol part of the url, e.g. osfs or ftp.

username

str, optional – A username, or None.

password

str, optional – A password, or None.

resource

str – A resource, typically a domain and path, e.g. ftp.example.org/dir.

params

dict – A dictionary of parameters extracted from the query string.

path

str, optional – A path within the filesystem, or None.

fs.opener.parse.parse_fs_url(fs_url)

Parse a Filesystem URL and return a ParseResult.

Parameters:fs_url (str) – A filesystem URL.
Returns:a parse result instance.
Return type:ParseResult
Raises:ParseError – if the FS URL is not valid.

fs.opener.registry

Registry class mapping protocols and FS URLs to their Opener.

class fs.opener.registry.Registry(default_opener=u'osfs')

A registry for Opener instances.

get_opener(protocol)

Get the opener class associated to a given protocol.

Parameters:

protocol (str) – A filesystem protocol.

Returns:

an opener instance.

Return type:

Opener

Raises:
  • UnsupportedProtocol – If no opener could be found for the given protocol.
  • EntryPointLoadingError – If the returned entry point is not an Opener subclass or could not be loaded successfully.
manage_fs(**kwds)

Get a context manager to open and close a filesystem.

Parameters:
  • fs_url (FS or str) – A filesystem instance or a FS URL.
  • create (bool, optional) – If True, then create the filesystem if it doesn’t already exist.
  • writeable (bool, optional) – If True, then the filesystem must be writeable.
  • cwd (str) – The current working directory, if opening a OSFS.

Sometimes it is convenient to be able to pass either a FS object or an FS URL to a function. This context manager handles the required logic for that.

Example

>>> def print_ls(list_fs):
...     """List a directory."""
...     with manage_fs(list_fs) as fs:
...         print(' '.join(fs.listdir()))

This function may be used in two ways. You may either pass a str, as follows:

>>> print_list('zip://projects.zip')

Or, an filesystem instance:

>>> from fs.osfs import OSFS
>>> projects_fs = OSFS('~/')
>>> print_list(projects_fs)
open(fs_url, writeable=True, create=False, cwd=u'.', default_protocol=u'osfs')

Open a filesystem from a FS URL.

Returns a tuple of a filesystem object and a path. If there is no path in the FS URL, the path value will be None.

Parameters:
  • fs_url (str) – A filesystem URL.
  • writeable (bool, optional) – True if the filesystem must be writeable.
  • create (bool, optional) – True if the filesystem should be created if it does not exist.
  • cwd (str, optional) – The current working directory, or None.
Returns:

a tuple of (<filesystem>, <path from url>)

Return type:

(FS, str)

open_fs(fs_url, writeable=False, create=False, cwd=u'.', default_protocol=u'osfs')

Open a filesystem from a FS URL (ignoring the path component).

Parameters:
  • fs_url (str) – A filesystem URL.
  • writeable (bool, optional) – True if the filesystem must be writeable.
  • create (bool, optional) – True if the filesystem should be created if it does not exist.
  • cwd (str, optional) – The current working directory (generally only relevant for OS filesystems).
  • default_protocol (str) – The protocol to use if one is not supplied in the FS URL (defaults to "osfs").
Returns:

A filesystem instance.

Return type:

FS

protocols

list – the list of supported protocols.

fs.opener.errors

Errors raised when attempting to open a filesystem.

exception fs.opener.errors.EntryPointError

Bases: fs.opener.errors.OpenerError

An entry point could not be loaded.

exception fs.opener.errors.NotWriteable

Bases: fs.opener.errors.OpenerError

A writable FS could not be created.

exception fs.opener.errors.OpenerError

Bases: exceptions.Exception

Base exception for opener related errors.

exception fs.opener.errors.ParseError

Bases: exceptions.ValueError

Attempt to parse an invalid FS URL.

exception fs.opener.errors.UnsupportedProtocol

Bases: fs.opener.errors.OpenerError

No opener found for the given protocol.

fs.path

Useful functions for working with PyFilesystem paths.

This is broadly similar to the standard os.path module but works with paths in the canonical format expected by all FS objects (that is, separated by forward slashes and with an optional leading slash).

See Paths for an explanation of PyFilesystem paths.

fs.path.abspath(path)

Convert the given path to an absolute path.

Since FS objects have no concept of a current directory, this simply adds a leading / character if the path doesn’t already have one.

Parameters:path (str) – A PyFilesytem path.
Returns:An absolute path.
Return type:str
fs.path.basename(path)

Return the basename of the resource referenced by a path.

This is always equivalent to the ‘tail’ component of the value returned by split(path).

Parameters:path (str) – A PyFilesytem path.
Returns:the name of the resource at the given path.
Return type:str

Example

>>> basename('foo/bar/baz')
'baz'
>>> basename('foo/bar')
'bar'
>>> basename('foo/bar/')
''
fs.path.combine(path1, path2)

Join two paths together.

This is faster than join(), but only works when the second path is relative, and there are no back references in either path.

Parameters:
  • path1 (str) – A PyFilesytem path.
  • path2 (str) – A PyFilesytem path.
Returns:

The joint path.

Return type:

str

Example

>>> combine("foo/bar", "baz")
'foo/bar/baz'
fs.path.dirname(path)

Return the parent directory of a path.

This is always equivalent to the ‘head’ component of the value returned by split(path).

Parameters:path (str) – A PyFilesytem path.
Returns:the parent directory of the given path.
Return type:str

Example

>>> dirname('foo/bar/baz')
'foo/bar'
>>> dirname('/foo/bar')
'/foo'
>>> dirname('/foo')
'/'
fs.path.forcedir(path)

Ensure the path ends with a trailing forward slash.

Parameters:path (str) – A PyFilesytem path.
Returns:The path, ending with a slash.
Return type:str

Example

>>> forcedir("foo/bar")
'foo/bar/'
>>> forcedir("foo/bar/")
'foo/bar/'
>>> forcedir("foo/spam.txt")
'foo/spam.txt'
fs.path.frombase(path1, path2)

Get the final path of path2 that isn’t in path1.

Parameters:
  • path1 (str) – A PyFilesytem path.
  • path2 (str) – A PyFilesytem path.
Returns:

the final part of path2.

Return type:

str

Example

>>> frombase('foo/bar/', 'foo/bar/baz/egg')
'baz/egg'
fs.path.isabs(path)

Check if a path is an absolute path.

Parameters:path (str) – A PyFilesytem path.
Returns:True if the path is absolute (starts with a '/').
Return type:bool
fs.path.isbase(path1, path2)

Check if path1 is a base of path2.

Parameters:
  • path1 (str) – A PyFilesytem path.
  • path2 (str) – A PyFilesytem path.
Returns:

True if path2 starts with path1

Return type:

bool

Example

>>> isbase('foo/bar', 'foo/bar/baz/egg.txt')
True
fs.path.isdotfile(path)

Detect if a path references a dot file.

Parameters:path (str) – Path to check.
Returns:True if the resource name starts with a '.'.
Return type:bool

Example

>>> isdotfile('.baz')
True
>>> isdotfile('foo/bar/.baz')
True
>>> isdotfile('foo/bar.baz')
False
fs.path.isparent(path1, path2)

Check if path1 is a parent directory of path2.

Parameters:
  • path1 (str) – A PyFilesytem path.
  • path2 (str) – A PyFilesytem path.
Returns:

True if path1 is a parent directory of path2

Return type:

bool

Example

>>> isparent("foo/bar", "foo/bar/spam.txt")
True
>>> isparent("foo/bar/", "foo/bar")
True
>>> isparent("foo/barry", "foo/baz/bar")
False
>>> isparent("foo/bar/baz/", "foo/baz/bar")
False
fs.path.issamedir(path1, path2)

Check if two paths reference a resource in the same directory.

Parameters:
  • path1 (str) – A PyFilesytem path.
  • path2 (str) – A PyFilesytem path.
Returns:

True if the two resources are in the same directory.

Return type:

bool

Example

>>> issamedir("foo/bar/baz.txt", "foo/bar/spam.txt")
True
>>> issamedir("foo/bar/baz/txt", "spam/eggs/spam.txt")
False
fs.path.iswildcard(path)

Check if a path ends with a wildcard.

Parameters:path (str) – A PyFilesystem path.
Returns:True if path ends with a wildcard.
Return type:bool

Example

>>> iswildcard('foo/bar/baz.*')
True
>>> iswildcard('foo/bar')
False
fs.path.iteratepath(path)

Iterate over the individual components of a path.

Parameters:path (str) – Path to iterate over.
Returns:A list of path components.
Return type:list

Example

>>> iteratepath('/foo/bar/baz')
['foo', 'bar', 'baz']
fs.path.join(*paths)

Join any number of paths together.

Parameters:*paths (str) – Paths to join, given as positional arguments.
Returns:The joined path.
Return type:str

Example

>>> join('foo', 'bar', 'baz')
'foo/bar/baz'
>>> join('foo/bar', '../baz')
'foo/baz'
>>> join('foo/bar', '/baz')
'/baz'
fs.path.normpath(path)

Normalize a path.

This function simplifies a path by collapsing back-references and removing duplicated separators.

Parameters:path (str) – Path to normalize.
Returns:A valid FS path.
Return type:str

Example

>>> normpath("/foo//bar/frob/../baz")
'/foo/bar/baz'
>>> normpath("foo/../../bar")
Traceback (most recent call last)
    ...
IllegalBackReference: Too many backrefs in 'foo/../../bar'
fs.path.parts(path)

Split a path in to its component parts.

Parameters:path (str) – Path to split in to parts.
Returns:List of components
Return type:list

Example

>>> parts('/foo/bar/baz')
['/', 'foo', 'bar', 'baz']
fs.path.recursepath(path, reverse=False)

Get intermediate paths from the root to the given path.

Parameters:
  • path (str) – A PyFilesystem path
  • reverse (bool, optional) – Reverses the order of the paths (default False).
Returns:

A list of paths.

Return type:

list

Example

>>> recursepath('a/b/c')
['/', '/a', '/a/b', '/a/b/c']
fs.path.relativefrom(base, path)

Return a path relative from a given base path.

Insert backrefs as appropriate to reach the path from the base.

Parameters:
  • base (str) – Path to a directory.
  • path (str) – Path to make relative.
Returns:

the path to base from path.

Return type:

str

>>> relativefrom("foo/bar", "baz/index.html")
'../../baz/index.html'
fs.path.relpath(path)

Convert the given path to a relative path.

This is the inverse of abspath, stripping a leading '/' from the path if it is present.

Parameters:path (str) – A path to adjust.
Returns:A relative path.
Return type:str

Example

>>> relpath('/a/b')
'a/b'
fs.path.split(path)

Split a path into (head, tail) pair.

This function splits a path into a pair (head, tail) where ‘tail’ is the last pathname component and ‘head’ is all preceding components.

Parameters:path (str) – Path to split
Returns:a tuple containing the head and the tail of the path.
Return type:(str, str)

Example

>>> split("foo/bar")
('foo', 'bar')
>>> split("foo/bar/baz")
('foo/bar', 'baz')
>>> split("/foo/bar/baz")
('/foo/bar', 'baz')
fs.path.splitext(path)

Split the extension from the path.

Parameters:path (str) – A path to split.
Returns:A tuple containing the path and the extension.
Return type:(str, str)

Example

>>> splitext('baz.txt')
('baz', '.txt')
>>> splitext('foo/bar/baz.txt')
('foo/bar/baz', '.txt')

fs.permissions

Abstract permissions container.

class fs.permissions.Permissions(names=None, mode=None, user=None, group=None, other=None, sticky=None, setuid=None, setguid=None)

An abstraction for file system permissions.

Permissions objects store information regarding the permissions on a resource. It supports Linux permissions, but is generic enough to manage permission information from almost any filesystem.

Parameters:
  • names (list, optional) – A list of permissions.
  • mode (int, optional) – A mode integer.
  • user (str, optional) – A triplet of user permissions, e.g. "rwx" or "r--"
  • group (str, optional) – A triplet of group permissions, e.g. "rwx" or "r--"
  • other (str, optional) – A triplet of other permissions, e.g. "rwx" or "r--"
  • sticky (bool, optional) – A boolean for the sticky bit.
  • setuid (bool, optional) – A boolean for the setuid bit.
  • setguid (bool, optional) – A boolean for the setguid bit.

Example

>>> from fs.permissions import Permissions
>>> p = Permissions(user='rwx', group='rw-', other='r--')
>>> print(p)
rwxrw-r--
>>> p.mode
500
>>> oct(p.mode)
'0764'
add(*permissions)

Add permission(s).

Parameters:*permissions (str) – Permission name(s), such as 'u_w' or 'u_x'.
as_str()

Get a Linux-style string representation of permissions.

check(*permissions)

Check if one or more permissions are enabled.

Parameters:*permissions (str) – Permission name(s), such as 'u_w' or 'u_x'.
Returns:True if all given permissions are set.
Return type:bool
copy()

Make a copy of this permissions object.

classmethod create(init=None)

Create a permissions object from an initial value.

Parameters:init (int or list or None) – May be None to use 0o777 permissions, a mode integer, or a list of permission names.
Returns:mode integer that may be used for instance by os.makedir.
Return type:int

Example

>>> Permissions.create(None)
Permissions(user='rwx', group='rwx', other='rwx')
>>> Permissions.create(0o700)
Permissions(user='rwx', group='', other='')
>>> Permissions.create(['u_r', 'u_w', 'u_x'])
Permissions(user='rwx', group='', other='')
dump()

Get a list suitable for serialization.

g_r

Boolean for ‘g_r’ permission.

g_w

Boolean for ‘g_w’ permission.

g_x

Boolean for ‘g_x’ permission.

classmethod get_mode(init)

Convert an initial value to a mode integer.

classmethod load(permissions)

Load a serialized permissions object.

mode

int – mode integer.

o_r

Boolean for ‘o_r’ permission.

o_w

Boolean for ‘o_w’ permission.

o_x

Boolean for ‘o_x’ permission.

classmethod parse(ls)

Parse permissions in Linux notation.

remove(*permissions)

Remove permission(s).

Parameters:*permissions (str) – Permission name(s), such as 'u_w' or 'u_x'.s
setguid

Boolean for ‘setguid’ permission.

setuid

Boolean for ‘setuid’ permission.

sticky

Boolean for ‘sticky’ permission.

u_r

Boolean for ‘u_r’ permission.

u_w

Boolean for ‘u_w’ permission.

u_x

Boolean for ‘u_x’ permission.

fs.permissions.make_mode(init)

Make a mode integer from an initial value.

fs.tools

Miscellaneous tools for operating on filesystems.

fs.tools.copy_file_data(src_file, dst_file, chunk_size=None)

Copy data from one file object to another.

Parameters:
  • src_file (io.IOBase) – File open for reading.
  • dst_file (io.IOBase) – File open for writing.
  • chunk_size (int, optional) – Number of bytes to copy at a time (or None to use sensible default).
fs.tools.get_intermediate_dirs(fs, dir_path)

Get a list of non-existing intermediate directories.

Parameters:
  • fs (FS) – A filesystem instance.
  • dir_path (str) – A path to a new directory on the filesystem.
Returns:

A list of non-existing paths.

Return type:

list

Raises:

fs.errors.DirectoryExpected – If a path component references a file and not a directory.

fs.tools.remove_empty(fs, path)

Remove all empty parents.

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str) – Path to a directory on the filesystem.

fs.tree

Render a FS object as text tree views.

Color is supported on UNIX terminals.

fs.tree.render(fs, path=u'/', file=None, encoding=None, max_levels=5, with_color=None, dirs_first=True, exclude=None, filter=None)

Render a directory structure in to a pretty tree.

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str) – The path of the directory to start rendering from (defaults to root folder, i.e. '/').
  • file (io.IOBase) – An open file-like object to render the tree, or None for stdout.
  • encoding (str or None) – Unicode encoding, or None to auto-detect.
  • max_levels (int or None) – Maximum number of levels to display, or None for no maximum.
  • with_color (bool or None) – Enable terminal color output, or None to auto-detect terminal.
  • dirs_first (bool) – Show directories first.
  • exclude (list or None) – Option list of directory patterns to exclude from the tree render.
  • filter (list or None) – Optional list of files patterns to match in the tree render.
Returns:

A tuple of (<directory count>, <file count>).

Return type:

(int, int)

fs.walk

Machinery for walking a filesystem.

Walking a filesystem means recursively visiting a directory and any sub-directories. It is a fairly common requirement for copying, searching etc. See Walking for details.

class fs.walk.BoundWalker(fs, walker_class=<class 'fs.walk.Walker'>)

A class that binds a Walker instance to a FS instance.

Parameters:
  • fs (FS) – A filesystem instance.
  • walker_class (type, optional) – A WalkerBase sub-class. The default uses Walker.

You will typically not need to create instances of this class explicitly. Filesystems have a walk property which returns a BoundWalker object.

Example

>>> import fs
>>> home_fs = fs.open_fs('~/')
>>> home_fs.walk
BoundWalker(OSFS('/Users/will', encoding='utf-8'))

A BoundWalker is callable. Calling it is an alias for walk.

dirs(path=u'/', **kwargs)

Walk a filesystem, yielding absolute paths to directories.

Parameters:

path (str) – A path to a directory.

Keyword Arguments:
 
  • ignore_errors (bool) – If True, any errors reading a directory will be ignored, otherwise exceptions will be raised.
  • on_error (callable) – If ignore_errors is False, then this callable will be invoked with a path and the exception object. It should return True to ignore the error, or False to re-raise it.
  • search (str) – If 'breadth' then the directory will be walked top down. Set to 'depth' to walk bottom up.
  • exclude_dirs (list) – A list of patterns that will be used to filter out directories from the walk, e.g. ['*.svn', '*.git'].
  • max_depth (int, optional) – Maximum directory depth to walk.
Returns:

an iterable of directory paths (absolute from the filesystem root).

Return type:

iterable

This method invokes Walker.dirs with the bound FS object.

files(path=u'/', **kwargs)

Walk a filesystem, yielding absolute paths to files.

Parameters:

path (str) – A path to a directory.

Keyword Arguments:
 
  • ignore_errors (bool) – If True, any errors reading a directory will be ignored, otherwise exceptions will be raised.
  • on_error (callable) – If ignore_errors is False, then this callable will be invoked with a path and the exception object. It should return True to ignore the error, or False to re-raise it.
  • search (str) – If 'breadth' then the directory will be walked top down. Set to 'depth' to walk bottom up.
  • filter (list) – If supplied, this parameter should be a list of file name patterns, e.g. ['*.py']. Files will only be returned if the final component matches one of the patterns.
  • exclude_dirs (list) – A list of patterns that will be used to filter out directories from the walk, e.g. ['*.svn', '*.git'].
  • max_depth (int, optional) – Maximum directory depth to walk.
Returns:

An iterable of file paths (absolute from the filesystem root).

Return type:

Iterable

This method invokes Walker.files with the bound FS object.

info(path=u'/', namespaces=None, **kwargs)

Walk a filesystem, yielding path and Info of resources.

Parameters:
  • path (str, optional) –
  • namespaces (list, optional) – A list of namespaces to include in the resource information, e.g. ['basic', 'access'] (defaults to ['basic']).
Keyword Arguments:
 
  • ignore_errors (bool) – If True, any errors reading a directory will be ignored, otherwise exceptions will be raised.
  • on_error (callable) – If ignore_errors is False, then this callable will be invoked with a path and the exception object. It should return True to ignore the error, or False to re-raise it.
  • search (str) – If 'breadth' then the directory will be walked top down. Set to 'depth' to walk bottom up.
  • filter (list) – If supplied, this parameter should be a list of file name patterns, e.g. ['*.py']. Files will only be returned if the final component matches one of the patterns.
  • exclude_dirs (list) – A list of patterns that will be used to filter out directories from the walk, e.g. ['*.svn', '*.git'].
  • max_depth (int, optional) – Maximum directory depth to walk.
Returns:

an iterable yielding tuples of (<absolute path>, <resource info>).

Return type:

Iterable

This method invokes Walker.info with the bound FS object.

walk(path=u'/', namespaces=None, **kwargs)

Walk the directory structure of a filesystem.

Parameters:
  • path (str, optional) –
  • namespaces (list, optional) – A list of namespaces to include in the resource information, e.g. ['basic', 'access'] (defaults to ['basic']).
Keyword Arguments:
 
  • ignore_errors (bool) – If True, any errors reading a directory will be ignored, otherwise exceptions will be raised.
  • on_error (callable) – If ignore_errors is False, then this callable will be invoked with a path and the exception object. It should return True to ignore the error, or False to re-raise it.
  • search (str) – If 'breadth' then the directory will be walked top down. Set to 'depth' to walk bottom up.
  • filter (list) – If supplied, this parameter should be a list of file name patterns, e.g. ['*.py']. Files will only be returned if the final component matches one of the patterns.
  • exclude_dirs (list) – A list of patterns that will be used to filter out directories from the walk, e.g. ['*.svn', '*.git'].
  • max_depth (int, optional) – Maximum directory depth to walk.
Returns:

an iterator of (<path>, <dirs>, <files>) named tuples, where <path> is an absolute path to a directory, and <dirs> and <files> are a list of Info objects for directories and files in <path>.

Return type:

Iterator

Example

>>> home_fs = open_fs('~/')
>>> walker = Walker(filter=['*.py'])
>>> for path, dirs, files in walker.walk(home_fs, namespaces=['details']):
...     print("[{}]".format(path))
...     print("{} directories".format(len(dirs)))
...     total = sum(info.size for info in files)
...     print("{} bytes {}".format(total))

This method invokes Walker.walk with bound FS object.

class fs.walk.Step(path, dirs, files)
dirs

Alias for field number 1

files

Alias for field number 2

path

Alias for field number 0

class fs.walk.Walker(ignore_errors=False, on_error=None, search=u'breadth', filter=None, exclude_dirs=None, max_depth=None)

A walker object recursively lists directories in a filesystem.

Parameters:
  • ignore_errors (bool, optional) – If True, any errors reading a directory will be ignored, otherwise exceptions will be raised.
  • on_error (callable, optional) – If ignore_errors is False, then this callable will be invoked for a path and the exception object. It should return True to ignore the error, or False to re-raise it.
  • search (str, optional) – If 'breadth' then the directory will be walked top down. Set to 'depth' to walk bottom up.
  • filter (list, optional) – If supplied, this parameter should be a list of filename patterns, e.g. ['*.py']. Files will only be returned if the final component matches one of the patterns.
  • exclude_dirs (list, optional) – A list of patterns that will be used to filter out directories from the walk. e.g. ['*.svn', '*.git'].
  • max_depth (int, optional) – Maximum directory depth to walk.
classmethod bind(fs)

Bind a Walker instance to a given filesystem.

This binds in instance of the Walker to a given filesystem, so that you won’t need to explicitly provide the filesystem as a parameter.

Parameters:fs (FS) – A filesystem object.
Returns:a bound walker.
Return type:BoundWalker

Example

>>> from fs import open_fs
>>> from fs.walk import Walker
>>> home_fs = open_fs('~/')
>>> walker = Walker.bind(home_fs)
>>> for path in walker.files(filter=['*.py']):
...     print(path)

Unless you have written a customized walker class, you will be unlikely to need to call this explicitly, as filesystem objects already have a walk attribute which is a bound walker object.

Example

>>> from fs import open_fs
>>> home_fs = open_fs('~/')
>>> for path in home_fs.walk.files(filter=['*.py']):
...     print(path)
check_file(fs, info)

Check if a filename should be included.

Override to exclude files from the walk.

Parameters:
  • fs (FS) – A filesystem instance.
  • info (Info) – A resource info object.
Returns:

True if the file should be included.

Return type:

bool

check_open_dir(fs, path, info)

Check if a directory should be opened.

Override to exclude directories from the walk.

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str) – Path to directory.
  • info (Info) – A resource info object for the directory.
Returns:

True if the directory should be opened.

Return type:

bool

check_scan_dir(fs, path, info)

Check if a directory should be scanned.

Override to omit scanning of certain directories. If a directory is omitted, it will appear in the walk but its files and sub-directories will not.

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str) – Path to directory.
  • info (Info) – A resource info object for the directory.
Returns:

True if the directory should be scanned.

Return type:

bool

dirs(fs, path=u'/')

Walk a filesystem, yielding absolute paths to directories.

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str, optional) – A path to a directory on the filesystem.
Yields:

str – absolute path to directories on the filesystem found recursively within the given directory.

files(fs, path=u'/')

Walk a filesystem, yielding absolute paths to files.

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str, optional) – A path to a directory on the filesystem.
Yields:

str – absolute path to files on the filesystem found recursively within the given directory.

info(fs, path=u'/', namespaces=None)

Walk a filesystem, yielding tuples of (<path>, <info>).

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str, optional) – A path to a directory on the filesystem.
  • namespaces (list, optional) – A list of additional namespaces to add to the Info objects.
Yields:

(str, Info) – a tuple of (<absolute path>, <resource info>).

walk(fs, path=u'/', namespaces=None)

Walk the directory structure of a filesystem.

Parameters:
  • fs (FS) – A filesystem instance.
  • path (str, optional) – A path to a directory on the filesystem.
  • namespaces (list, optional) – A list of additional namespaces to add to the Info objects.
Returns:

an iterator of Step instances.

Return type:

collections.Iterator

The return value is an iterator of (<path>, <dirs>, <files>) named tuples, where <path> is an absolute path to a directory, and <dirs> and <files> are a list of Info objects for directories and files in <path>.

Example

>>> home_fs = open_fs('~/')
>>> walker = Walker(filter=['*.py'])
>>> namespaces = ['details']
>>> for path, dirs, files in walker.walk(home_fs, namespaces)
...    print("[{}]".format(path))
...    print("{} directories".format(len(dirs)))
...    total = sum(info.size for info in files)
...    print("{} bytes {}".format(total))

fs.wildcard

Match wildcard filenames.

fs.wildcard.get_matcher(patterns, case_sensitive)

Get a callable that matches names against the given patterns.

Parameters:
  • patterns (list) – A list of wildcard pattern. e.g. ["*.py", "*.pyc"]
  • case_sensitive (bool) – If True, then the callable will be case sensitive, otherwise it will be case insensitive.
Returns:

a matcher that will return True if the name given as an argument matches any of the given patterns.

Return type:

callable

Example

>>> from fs import wildcard
>>> is_python = wildcard.get_matcher(['*.py'], True)
>>> is_python('__init__.py')
True
>>> is_python('foo.txt')
False
fs.wildcard.imatch(pattern, name)

Test whether a name matches a wildcard pattern (case insensitive).

Parameters:
  • pattern (str) – A wildcard pattern, e.g. "*.py".
  • name (bool) – A filename.
Returns:

True if the filename matches the pattern.

Return type:

bool

fs.wildcard.imatch_any(patterns, name)

Test if a name matches any of a list of patterns (case insensitive).

Will return True if patterns is an empty list.

Parameters:
  • patterns (list) – A list of wildcard pattern, e.g ["*.py", "*.pyc"]
  • name (str) – A filename.
Returns:

True if the name matches at least one of the patterns.

Return type:

bool

fs.wildcard.match(pattern, name)

Test whether a name matches a wildcard pattern.

Parameters:
  • pattern (str) – A wildcard pattern, e.g. "*.py".
  • name (bool) – A filename.
Returns:

True if the filename matches the pattern.

Return type:

bool

fs.wildcard.match_any(patterns, name)

Test if a name matches any of a list of patterns.

Will return True if patterns is an empty list.

Parameters:
  • patterns (list) – A list of wildcard pattern, e.g ["*.py", "*.pyc"]
  • name (str) – A filename.
Returns:

True if the name matches at least one of the patterns.

Return type:

bool

fs.wrap

Collection of useful WrapFS subclasses.

Here’s an example that opens a filesystem then makes it read only:

>>> from fs import open_fs
>>> from fs.wrap import read_only
>>> projects_fs = open_fs('~/projects')
>>> read_only_projects_fs = read_only(projects_fs)
>>> read_only_projects_fs.remove('__init__.py')
Traceback (most recent call last):
  ...
fs.errors.ResourceReadOnly: resource '__init__.py' is read only
class fs.wrap.WrapCachedDir(wrap_fs)

Caches filesystem directory information.

This filesystem caches directory information retrieved from a scandir call. This may speed up code that calls isdir, isfile, or gettype too frequently.

Note

Using this wrap will prevent changes to directory information being visible to the filesystem object. Consequently it is best used only in a fairly limited scope where you don’t expected anything on the filesystem to change.

class fs.wrap.WrapReadOnly(wrap_fs)

Makes a Filesystem read-only.

Any call that would would write data or modify the filesystem in any way will raise a ResourceReadOnly exception.

fs.wrap.cache_directory(fs)

Make a filesystem that caches directory information.

Parameters:fs (FS) – A filesystem instance.
Returns:A filesystem that caches results of scandir, isdir and other methods which read directory information.
Return type:FS
fs.wrap.read_only(fs)

Make a read-only filesystem.

Parameters:fs (FS) – A filesystem instance.
Returns:A read only version of fs
Return type:FS

fs.wrapfs

Base class for filesystem wrappers.

class fs.wrapfs.WrapFS(wrap_fs)

A proxy for a filesystem object.

This class exposes an filesystem interface, where the data is stored on another filesystem(s), and is the basis for SubFS and other virtual filesystems.

delegate_fs()

Get the proxied filesystem.

This method should return a filesystem for methods not associated with a path, e.g. getmeta.

delegate_path(path)

Encode a path for proxied filesystem.

Parameters:path (str) – A path on the filesystem.
Returns:a tuple of (<filesystem>, <new_path>)
Return type:(FS, str)

Indices and tables