API

`GCSFileSystem`(args, *kwargs)	Connect to Google Cloud Storage.
`GCSFileSystem.cat`(path[, recursive, on_error])	Fetch (potentially multiple) paths' contents
`GCSFileSystem.du`(path[, total, maxdepth, ...])	Space used by files and optionally directories within a path
`GCSFileSystem.exists`(path, **kwargs)	Is there a file at the given path
`GCSFileSystem.get`(rpath, lpath[, recursive, ...])	Copy file(s) to local.
`GCSFileSystem.glob`(path, **kwargs)	Find files by glob-matching.
`GCSFileSystem.info`(path, **kwargs)	Give details of entry at path
`GCSFileSystem.ls`(path[, detail])	List objects at path.
`GCSFileSystem.mkdir`(path[, acl, ...])	New bucket
`GCSFileSystem.mv`(path1, path2[, recursive, ...])	Move file(s) from one location to another
`GCSFileSystem.open`(path[, mode, block_size, ...])	Return a file-like object from the filesystem
`GCSFileSystem.put`(lpath, rpath[, recursive, ...])	Copy file(s) from local.
`GCSFileSystem.read_block`(fn, offset, length)	Read a block of bytes from
`GCSFileSystem.rm`(path[, recursive, ...])	Delete files.
`GCSFileSystem.tail`(path[, size])	Get the last `size` bytes from file
`GCSFileSystem.touch`(path[, truncate])	Create empty file, or update timestamp
`GCSFileSystem.get_mapper`([root, check, ...])	Create key/value store based on this file-system

`GCSFile`(gcsfs, path[, mode, block_size, ...])
`GCSFile.close`()	Close file
`GCSFile.flush`([force])	Write buffered data to backend store.
`GCSFile.info`()	File information about this path
`GCSFile.read`([length])	Return data from cache, or fetch pieces as necessary
`GCSFile.seek`(loc[, whence])	Set current file location
`GCSFile.tell`()	Current file location
`GCSFile.write`(data)	Write data to buffer.

class gcsfs.core.GCSFileSystem(*args, **kwargs)[source]

Connect to Google Cloud Storage.

The following modes of authentication are supported:

token=None, GCSFS will attempt to guess your credentials in the following order: gcloud CLI default, gcsfs cached token, google compute metadata service, anonymous.
token='google_default', your default gcloud credentials will be used, which are typically established by doing gcloud login in a terminal.
token='cache', credentials from previously successful gcsfs authentication will be used (use this after “browser” auth succeeded)
token='anon', no authentication is performed, and you can only access data which is accessible to allUsers (in this case, the project and access level parameters are meaningless)
token='browser', you get an access code with which you can authenticate via a specially provided URL
if token='cloud', we assume we are running within google compute or google container engine, and query the internal metadata directly for a token.
you may supply a token generated by the [gcloud](https://cloud.google.com/sdk/docs/) utility; this is either a python dictionary, the name of a file containing the JSON returned by logging in with the gcloud CLI tool, or a Credentials object. gcloud typically stores its tokens in locations such as ~/.config/gcloud/application_default_credentials.json, ~/.config/gcloud/credentials, or ~\AppData\Roaming\gcloud\credentials, etc.

Specific methods, (eg. ls, info, …) may return object details from GCS. These detailed listings include the [object resource](https://cloud.google.com/storage/docs/json_api/v1/objects#resource)

GCS does not include “directory” objects but instead generates directories by splitting [object names](https://cloud.google.com/storage/docs/key-terms). This means that, for example, a directory does not need to exist for an object to be created within it. Creating an object implicitly creates it’s parent directories, and removing all objects from a directory implicitly deletes the empty directory.

GCSFileSystem generates listing entries for these implied directories in listing apis with the object properties:

“name”string
The “{bucket}/{name}” path of the dir, used in calls to GCSFileSystem or GCSFile.

“bucket”string
The name of the bucket containing this object.

“kind” : ‘storage#object’

“size” : 0

“storageClass” : ‘DIRECTORY’

type: ‘directory’ (fsspec compat)

GCSFileSystem maintains a per-implied-directory cache of object listings and fulfills all object information and listing requests from cache. This implied, for example, that objects created via other processes will not be visible to the GCSFileSystem until the cache refreshed. Calls to GCSFileSystem.open and calls to GCSFile are not effected by this cache.

In the default case the cache is never expired. This may be controlled via the cache_timeout GCSFileSystem parameter or via explicit calls to GCSFileSystem.invalidate_cache.

Parameters

project (string) – project_id to work under. Note that this is not the same as, but often very similar to, the project name. This is required in order to list all the buckets you have access to within a project and to create/delete buckets, or update their access policies. If token='google_default', the value is overridden by the default, if token='anon', the value is ignored.
access (one of {'read_only', 'read_write', 'full_control'}) – Full control implies read/write as well as modifying metadata, e.g., access control.
token (None, dict or string) – (see description of authentication methods, above)
consistency ('none', 'size', 'md5') – Check method when writing files. Can be overridden in open().
cache_timeout (float, seconds) – Cache expiration time in seconds for object metadata cache. Set cache_timeout <= 0 for no caching, None for no cache expiration.
secure_serialize (bool (deprecated)) –
requester_pays (bool, or str default False) – Whether to use requester-pays requests. This will include your project ID project in requests as the userProject, and you’ll be billed for accessing data from requester-pays buckets. Optionally, pass a project-id here as a string to use that as the userProject.
session_kwargs (dict) – passed on to aiohttp.ClientSession; can contain, for example, proxy settings.
endpoint_url (str) – If given, use this URL (format protocol://host:port , without any path part) for communication. If not given, defaults to the value of environment variable “STORAGE_EMULATOR_HOST”; if that is not set either, will use the standard Google endpoint.
default_location (str) – Default location where buckets are created, like ‘US’ or ‘EUROPE-WEST3’. You can find a list of all available locations here: https://cloud.google.com/storage/docs/locations#available-locations
version_aware (bool) – Whether to support object versioning. If enabled this will require the user to have the necessary permissions for dealing with versioned objects.

property buckets: Return list of available project buckets.

cat(path, recursive=False, on_error='raise', **kwargs)

Fetch (potentially multiple) paths’ contents

Parameters

recursive (bool) – If True, assume the path(s) are directories, and get all the contained files
on_error ("raise", "omit", "return") – If raise, an underlying exception will be raised (converted to KeyError if the type is in self.missing_exceptions); if omit, keys with exception will simply not be included in the output; if “return”, all keys are included in the output, but the value will be bytes or an exception instance.
kwargs (passed to cat_file) –

Returns

dict of {path (contents} if there are multiple paths)
or the path has been otherwise expanded

cat_file(path, start=None, end=None, **kwargs)

Get the content of a file

Parameters

path (URL of file on this filesystems) –
start (int) – Bytes limits of the read. If negative, backwards from end, like usual python slices. Either can be None for start or end of file, respectively
end (int) – Bytes limits of the read. If negative, backwards from end, like usual python slices. Either can be None for start or end of file, respectively
kwargs (passed to open().) –

checksum(path)

Unique value for current version of file

If the checksum is the same from one moment to another, the contents are guaranteed to be the same. If the checksum changes, the contents might have changed.

This should normally be overridden; default will probably capture creation/modification timestamp (which would be good) or maybe access timestamp (which would be bad)

classmethod clear_instance_cache()

Clear the cache of filesystem instances.

Notes

Unless overridden by setting the cachable class attribute to False, the filesystem class stores a reference to newly created instances. This prevents Python’s normal rules around garbage collection from working, since the instances refcount will not drop to zero until clear_instance_cache is called.

copy(path1, path2, recursive=False, on_error=None, **kwargs)

Copy within two locations in the filesystem

on_error“raise”, “ignore”: If raise, any not-found exceptions will be raised; if ignore any not-found exceptions will cause the path to be skipped; defaults to raise unless recursive is true, where the default is ignore

cp(path1, path2, **kwargs): Alias of AbstractFileSystem.copy.

created(path)[source]: Return the created timestamp of a file as a datetime.datetime

classmethod current()

Return the most recently instantiated FileSystem

If no instance has been created, then create one with defaults

delete(path, recursive=False, maxdepth=None): Alias of AbstractFileSystem.rm.

disk_usage(path, total=True, maxdepth=None, **kwargs): Alias of AbstractFileSystem.du.

download(rpath, lpath, recursive=False, **kwargs): Alias of AbstractFileSystem.get.

du(path, total=True, maxdepth=None, withdirs=False, **kwargs)

Space used by files and optionally directories within a path

Directory size does not include the size of its contents.

Parameters

path (str) –
total (bool) – Whether to sum all the file sizes
maxdepth (int or None) – Maximum number of directory levels to descend, None for unlimited.
withdirs (bool) – Whether to include directory paths in the output.
kwargs (passed to find) –

Returns

Dict of {path (size} if total=False, or int otherwise, where numbers)
refer to bytes used.

end_transaction(): Finish write transaction, non-context version

exists(path, **kwargs): Is there a file at the given path

expand_path(path, recursive=False, maxdepth=None, **kwargs)

Turn one or more globs or directories into a list of all matching paths to files or directories.

kwargs are passed to glob or find, which may in turn call ls

find(path, maxdepth=None, withdirs=False, detail=False, **kwargs)

List all files below path.

Like posix find command without conditions

Parameters

path (str) –
maxdepth (int or None) – If not None, the maximum number of levels to descend
withdirs (bool) – Whether to include directory paths in the output. This is True when used by glob, but users usually only want files.
ls. (kwargs are passed to) –

static from_json(blob)

Recreate a filesystem instance from JSON representation

See .to_json() for the expected structure of the input

Parameters: blob (str) –
Return type: file system instance, not necessarily of this particular class.

property fsid: Persistent filesystem id that can be used to compare filesystems across sessions.

get(rpath, lpath, recursive=False, callback=<fsspec.callbacks.NoOpCallback object>, **kwargs)

Copy file(s) to local.

Copies a specific file or tree of files (if recursive=True). If lpath ends with a “/”, it will be assumed to be a directory, and target files will go within. Can submit a list of paths, which may be glob-patterns and will be expanded.

Calls get_file for each source.

get_file(rpath, lpath, callback=<fsspec.callbacks.NoOpCallback object>, outfile=None, **kwargs): Copy single remote file to local

get_mapper(root='', check=False, create=False, missing_exceptions=None)

Create key/value store based on this file-system

Makes a MutableMapping interface to the FS at the given root path. See fsspec.mapping.FSMap for further details.

getxattr(path, attr): Get user-defined metadata attribute

glob(path, **kwargs)

Find files by glob-matching.

If the path ends with ‘/’ and does not contain “*”, it is essentially the same as ls(path), returning only files.

We support "**", "?" and "[..]". We do not support ^ for pattern negation.

Search path names that contain embedded characters special to this implementation of glob may not produce expected results; e.g., ‘foo/bar/starredfilename’.

kwargs are passed to ls.

head(path, size=1024): Get the first size bytes from file

info(path, **kwargs)

Give details of entry at path

Returns a single dictionary, with exactly the same information as ls would with detail=True.

The default implementation should calls ls and could be overridden by a shortcut. kwargs are passed on to `ls().

Some file systems might not be able to measure the file’s size, in which case, the returned dict will include 'size': None.

Returns

dict with keys (name (full path in the FS), size (in bytes), type (file,)
directory, or something else) and other FS-specific keys.

invalidate_cache(path=None)[source]

Invalidate listing cache for given path, it is reloaded on next use.

Parameters: path (string or None) – If None, clear all listings cached else listings at or under given path.

isdir(path): Is this entry directory-like?

isfile(path): Is this entry file-like?

lexists(path, **kwargs): If there is a file at the given path (including broken links)

listdir(path, detail=True, **kwargs): Alias of AbstractFileSystem.ls.

ls(path, detail=True, **kwargs)

List objects at path.

This should include subdirectories and files at that location. The difference between a file and a directory must be clear when details are requested.

The specific keys, or perhaps a FileInfo class, or similar, is TBD, but must be consistent across implementations. Must include:

full path to the entry (without protocol)
size of the entry, in bytes. If the value cannot be determined, will be None.
type of entry, “file”, “directory” or other

Additional information may be present, appropriate to the file-system, e.g., generation, checksum, etc.

May use refresh=True|False to allow use of self._ls_from_cache to check for a saved listing and avoid calling the backend. This would be common where listing may be expensive.

Parameters

path (str) –
detail (bool) – if True, gives a list of dictionaries, where each is the same as the result of info(path). If False, gives a list of paths (str).
kwargs (may have additional backend-specific options, such as version) – information

Returns

List of strings if detail is False, or list of directory information
dicts if detail is True.

makedir(path, create_parents=True, **kwargs): Alias of AbstractFileSystem.mkdir.

makedirs(path, exist_ok=False)

Recursively make directories

Creates directory at path and any intervening required directories. Raises exception if, for instance, the path already exists but is a file.

Parameters

path (str) – leaf directory name
exist_ok (bool (False)) – If False, will error if the target already exists

merge(path, paths, acl=None): Concatenate objects within a single bucket

mkdir(path, acl='projectPrivate', default_acl='bucketOwnerFullControl', location=None, create_parents=True, enable_versioning=False, **kwargs)

New bucket

If path is more than just a bucket, will create bucket if create_parents=True; otherwise is a noop. If create_parents is False and bucket does not exist, will produce FileNotFFoundError.

Parameters

path (str) – bucket name. If contains ‘/’ (i.e., looks like subdir), will have no effect because GCS doesn’t have real directories.
acl (string, one of bACLs) – access for the bucket itself
default_acl (str, one of ACLs) – default ACL for objects created in this bucket
location (Optional[str]) – Location where buckets are created, like ‘US’ or ‘EUROPE-WEST3’. If not provided, defaults to self.default_location. You can find a list of all available locations here: https://cloud.google.com/storage/docs/locations#available-locations
create_parents (bool) – If True, creates the bucket in question, if it doesn’t already exist
enable_versioning (bool) – If True, creates the bucket in question with object versioning enabled.

mkdirs(path, exist_ok=False): Alias of AbstractFileSystem.makedirs.

modified(path)[source]: Return the modified timestamp of a file as a datetime.datetime

move(path1, path2, **kwargs): Alias of AbstractFileSystem.mv.

mv(path1, path2, recursive=False, maxdepth=None, **kwargs): Move file(s) from one location to another

open(path, mode='rb', block_size=None, cache_options=None, compression=None, **kwargs)

Return a file-like object from the filesystem

The resultant instance must function correctly in a context with block.

Parameters

path (str) – Target file
mode (str like 'rb', 'w') – See builtin open()
block_size (int) – Some indication of buffering - this is a value in bytes
cache_options (dict, optional) – Extra arguments to pass through to the cache.
compression (string or None) – If given, open file using compression codec. Can either be a compression name (a key in fsspec.compression.compr) or “infer” to guess the compression from the filename suffix.
encoding (passed on to TextIOWrapper for text mode) –
errors (passed on to TextIOWrapper for text mode) –
newline (passed on to TextIOWrapper for text mode) –

pipe(path, value=None, **kwargs)

Put value into path

(counterpart to cat)

Parameters

path (string or dict(str, bytes)) – If a string, a single remote location to put value bytes; if a dict, a mapping of {path: bytesvalue}.
value (bytes, optional) – If using a single path, these are the bytes to put there. Ignored if path is a dict

pipe_file(path, value, **kwargs): Set the bytes of given file

put(lpath, rpath, recursive=False, callback=<fsspec.callbacks.NoOpCallback object>, **kwargs)

Copy file(s) from local.

Copies a specific file or tree of files (if recursive=True). If rpath ends with a “/”, it will be assumed to be a directory, and target files will go within.

Calls put_file for each source.

put_file(lpath, rpath, callback=<fsspec.callbacks.NoOpCallback object>, **kwargs): Copy single file to remote

read_block(fn, offset, length, delimiter=None)

Read a block of bytes from

Starting at offset of the file, read length bytes. If delimiter is set then we ensure that the read starts and stops at delimiter boundaries that follow the locations offset and offset + length. If offset is zero then we start at zero. The bytestring returned WILL include the end delimiter string.

If offset+length is beyond the eof, reads to eof.

Parameters

fn (string) – Path to filename
offset (int) – Byte offset to start read
length (int) – Number of bytes to read. If None, read to end.
delimiter (bytes (optional)) – Ensure reading starts and stops at delimiter bytestring

Examples

>>> fs.read_block('data/file.csv', 0, 13)  
b'Alice, 100\nBo'
>>> fs.read_block('data/file.csv', 0, 13, delimiter=b'\n')  
b'Alice, 100\nBob, 200\n'

Use length=None to read to the end of the file. >>> fs.read_block(‘data/file.csv’, 0, None, delimiter=b’n’) # doctest: +SKIP b’Alice, 100nBob, 200nCharlie, 300’