Source code for s3fs.core

# -*- coding: utf-8 -*-
import logging
import os
import socket
import time

from fsspec import AbstractFileSystem
from fsspec.spec import AbstractBufferedFile
import boto3
from botocore.client import Config
from botocore.exceptions import ClientError, ParamValidationError, BotoCoreError

from s3fs.errors import translate_boto_error
from s3fs.utils import ParamKwargsHelper

logger = logging.getLogger('s3fs')
handle = logging.StreamHandler()
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s '
                              '- %(message)s')
handle.setFormatter(formatter)
logger.addHandler(handle)
if "S3FS_LOGGING_LEVEL" in os.environ:
    logger.setLevel(os.environ["S3FS_LOGGING_LEVEL"])

try:
    from boto3.s3.transfer import S3_RETRYABLE_ERRORS
except ImportError:
    S3_RETRYABLE_ERRORS = (
        socket.timeout,
    )

_VALID_FILE_MODES = {'r', 'w', 'a', 'rb', 'wb', 'ab'}

key_acls = {'private', 'public-read', 'public-read-write',
            'authenticated-read', 'aws-exec-read', 'bucket-owner-read',
            'bucket-owner-full-control'}
buck_acls = {'private', 'public-read', 'public-read-write',
             'authenticated-read'}


[docs]class S3FileSystem(AbstractFileSystem): """ Access S3 as if it were a file system. This exposes a filesystem-like API (ls, cp, open, etc.) on top of S3 storage. Provide credentials either explicitly (``key=``, ``secret=``) or depend on boto's credential methods. See boto3 documentation for more information. If no credentials are available, use ``anon=True``. Parameters ---------- anon : bool (False) Whether to use anonymous connection (public buckets only). If False, uses the key/secret given, or boto's credential resolver (environment variables, config files, EC2 IAM server, in that order) key : string (None) If not anonymous, use this access key ID, if specified secret : string (None) If not anonymous, use this secret access key, if specified token : string (None) If not anonymous, use this security token, if specified use_ssl : bool (True) Whether to use SSL in connections to S3; may be faster without, but insecure s3_additional_kwargs : dict of parameters that are used when calling s3 api methods. Typically used for things like "ServerSideEncryption". client_kwargs : dict of parameters for the boto3 client requester_pays : bool (False) If RequesterPays buckets are supported. default_block_size: int (None) If given, the default block size value used for ``open()``, if no specific value is given at all time. The built-in default is 5MB. default_fill_cache : Bool (True) Whether to use cache filling with open by default. Refer to ``S3File.open``. default_cache_type : string ('bytes') If given, the default cache_type value used for ``open()``. Set to "none" if no caching is desired. See fsspec's documentation for other available cache_type values. Default cache_type is 'bytes'. version_aware : bool (False) Whether to support bucket versioning. If enable this will require the user to have the necessary IAM permissions for dealing with versioned objects. config_kwargs : dict of parameters passed to ``botocore.client.Config`` kwargs : other parameters for boto3 session session : botocore Session object to be used for all connections. This session will be used inplace of creating a new session inside S3FileSystem. Examples -------- >>> s3 = S3FileSystem(anon=False) # doctest: +SKIP >>> s3.ls('my-bucket/') # doctest: +SKIP ['my-file.txt'] >>> with s3.open('my-bucket/my-file.txt', mode='rb') as f: # doctest: +SKIP ... print(f.read()) # doctest: +SKIP b'Hello, world!' """ root_marker = "" connect_timeout = 5 read_timeout = 15 default_block_size = 5 * 2**20 protocol = ['s3', 's3a'] _extra_tokenize_attributes = ('default_block_size',) def __init__(self, anon=False, key=None, secret=None, token=None, use_ssl=True, client_kwargs=None, requester_pays=False, default_block_size=None, default_fill_cache=True, default_cache_type='bytes', version_aware=False, config_kwargs=None, s3_additional_kwargs=None, session=None, username=None, password=None, **kwargs): if key and username: raise KeyError('Supply either key or username, not both') if secret and password: raise KeyError('Supply secret or password, not both') if username: key = username if password: secret = password self.anon = anon self.session = None self.passed_in_session = session if self.passed_in_session: self.session = self.passed_in_session self.key = key self.secret = secret self.token = token self.kwargs = kwargs if client_kwargs is None: client_kwargs = {} if config_kwargs is None: config_kwargs = {} self.default_block_size = default_block_size or self.default_block_size self.default_fill_cache = default_fill_cache self.default_cache_type = default_cache_type self.version_aware = version_aware self.client_kwargs = client_kwargs self.config_kwargs = config_kwargs self.req_kw = {'RequestPayer': 'requester'} if requester_pays else {} self.s3_additional_kwargs = s3_additional_kwargs or {} self.use_ssl = use_ssl self.s3 = self.connect() self._kwargs_helper = ParamKwargsHelper(self.s3) super().__init__() def _filter_kwargs(self, s3_method, kwargs): return self._kwargs_helper.filter_dict(s3_method.__name__, kwargs) def _call_s3(self, method, *akwarglist, **kwargs): kw2 = kwargs.copy() kw2.pop('Body', None) logger.debug("CALL: %s - %s - %s" % (method.__name__, akwarglist, kw2)) additional_kwargs = self._get_s3_method_kwargs(method, *akwarglist, **kwargs) return method(**additional_kwargs) def _get_s3_method_kwargs(self, method, *akwarglist, **kwargs): additional_kwargs = self.s3_additional_kwargs.copy() for akwargs in akwarglist: additional_kwargs.update(akwargs) # Add the normal kwargs in additional_kwargs.update(kwargs) # filter all kwargs return self._filter_kwargs(method, additional_kwargs)
[docs] def split_path(self, path): """ Normalise S3 path string into bucket and key. Parameters ---------- path : string Input path, like `s3://mybucket/path/to/file` Examples -------- >>> split_path("s3://mybucket/path/to/file") ['mybucket', 'path/to/file'] """ path = self._strip_protocol(path) path = path.lstrip('/') if '/' not in path: return path, "" else: return path.split('/', 1)
[docs] def connect(self, refresh=True): """ Establish S3 connection object. Parameters ---------- refresh : bool Whether to create new session/client, even if a previous one with the same parameters already exists. If False (default), an existing one will be used if possible """ if refresh is False: # back compat: we store whole FS instance now return self.s3 anon, key, secret, kwargs, ckwargs, token, ssl = ( self.anon, self.key, self.secret, self.kwargs, self.client_kwargs, self.token, self.use_ssl) if self.anon: from botocore import UNSIGNED conf = Config(connect_timeout=self.connect_timeout, read_timeout=self.read_timeout, signature_version=UNSIGNED, **self.config_kwargs) if not self.passed_in_session: self.session = boto3.Session(**self.kwargs) else: conf = Config(connect_timeout=self.connect_timeout, read_timeout=self.read_timeout, **self.config_kwargs) if not self.passed_in_session: self.session = boto3.Session(self.key, self.secret, self.token, **self.kwargs) logger.debug("Setting up s3fs instance") self.s3 = self.session.client('s3', config=conf, use_ssl=ssl, **self.client_kwargs) return self.s3
[docs] def get_delegated_s3pars(self, exp=3600): """Get temporary credentials from STS, appropriate for sending across a network. Only relevant where the key/secret were explicitly provided. Parameters ---------- exp : int Time in seconds that credentials are good for Returns ------- dict of parameters """ if self.anon: return {'anon': True} if self.token: # already has temporary cred return {'key': self.key, 'secret': self.secret, 'token': self.token, 'anon': False} if self.key is None or self.secret is None: # automatic credentials return {'anon': False} sts = self.session.client('sts') cred = sts.get_session_token(DurationSeconds=exp)['Credentials'] return {'key': cred['AccessKeyId'], 'secret': cred['SecretAccessKey'], 'token': cred['SessionToken'], 'anon': False}
def _open(self, path, mode='rb', block_size=None, acl='', version_id=None, fill_cache=None, cache_type=None, autocommit=True, requester_pays=None, **kwargs): """ Open a file for reading or writing Parameters ---------- path: string Path of file on S3 mode: string One of 'r', 'w', 'a', 'rb', 'wb', or 'ab'. These have the same meaning as they do for the built-in `open` function. block_size: int Size of data-node blocks if reading fill_cache: bool If seeking to new a part of the file beyond the current buffer, with this True, the buffer will be filled between the sections to best support random access. When reading only a few specific chunks out of a file, performance may be better if False. acl: str Canned ACL to set when writing version_id : str Explicit version of the object to open. This requires that the s3 filesystem is version aware and bucket versioning is enabled on the relevant bucket. encoding : str The encoding to use if opening the file in text mode. The platform's default text encoding is used if not given. cache_type : str See fsspec's documentation for available cache_type values. Set to "none" if no caching is desired. If None, defaults to ``self.default_cache_type``. requester_pays : bool (optional) If RequesterPays buckets are supported. If None, defaults to the value used when creating the S3FileSystem (which defaults to False.) kwargs: dict-like Additional parameters used for s3 methods. Typically used for ServerSideEncryption. """ if block_size is None: block_size = self.default_block_size if fill_cache is None: fill_cache = self.default_fill_cache if requester_pays is None: requester_pays = bool(self.req_kw) acl = acl or self.s3_additional_kwargs.get('ACL', '') kw = self.s3_additional_kwargs.copy() kw.update(kwargs) if not self.version_aware and version_id: raise ValueError("version_id cannot be specified if the filesystem " "is not version aware") if cache_type is None: cache_type = self.default_cache_type return S3File(self, path, mode, block_size=block_size, acl=acl, version_id=version_id, fill_cache=fill_cache, s3_additional_kwargs=kw, cache_type=cache_type, autocommit=autocommit, requester_pays=requester_pays) def _lsdir(self, path, refresh=False, max_items=None): bucket, prefix = self.split_path(path) prefix = prefix + '/' if prefix else "" if path not in self.dircache or refresh: try: logger.debug("Get directory listing page for %s" % path) pag = self.s3.get_paginator('list_objects_v2') config = {} if max_items is not None: config.update(MaxItems=max_items, PageSize=2 * max_items) it = pag.paginate(Bucket=bucket, Prefix=prefix, Delimiter='/', PaginationConfig=config, **self.req_kw) files = [] dircache = [] for i in it: dircache.extend(i.get('CommonPrefixes', [])) for c in i.get('Contents', []): c['type'] = 'file' c['size'] = c['Size'] files.append(c) if dircache: files.extend([{'Key': l['Prefix'][:-1], 'Size': 0, 'StorageClass': "DIRECTORY", 'type': 'directory', 'size': 0} for l in dircache]) for f in files: f['Key'] = '/'.join([bucket, f['Key']]) f['name'] = f['Key'] except ClientError as e: raise translate_boto_error(e) self.dircache[path] = files return self.dircache[path]
[docs] def mkdir(self, path, acl="", **kwargs): path = self._strip_protocol(path).rstrip('/') if not self._parent(path): if acl and acl not in buck_acls: raise ValueError('ACL not in %s', buck_acls) try: params = {"Bucket": path, 'ACL': acl} region_name = (kwargs.get("region_name", None) or self.client_kwargs.get("region_name", None)) if region_name: params['CreateBucketConfiguration'] = { 'LocationConstraint': region_name } self.s3.create_bucket(**params) self.invalidate_cache('') self.invalidate_cache(path) except ClientError as e: raise translate_boto_error(e) except ParamValidationError as e: raise ValueError('Bucket create failed %r: %s' % (path, e))
[docs] def rmdir(self, path): path = self._strip_protocol(path).rstrip('/') if not self._parent(path): try: self.s3.delete_bucket(Bucket=path) except ClientError as e: raise translate_boto_error(e) self.invalidate_cache(path) self.invalidate_cache('')
def _lsbuckets(self, refresh=False): if '' not in self.dircache or refresh: if self.anon: # cannot list buckets if not logged in return [] try: files = self.s3.list_buckets()['Buckets'] except ClientError: # listbucket permission missing return [] for f in files: f['Key'] = f['Name'] f['Size'] = 0 f['StorageClass'] = 'BUCKET' f['size'] = 0 f['type'] = 'directory' f['name'] = f['Name'] del f['Name'] self.dircache[''] = files return self.dircache[''] def _ls(self, path, refresh=False): """ List files in given bucket, or list of buckets. Listing is cached unless `refresh=True`. Note: only your buckets associated with the login will be listed by `ls('')`, not any public buckets (even if already accessed). Parameters ---------- path : string/bytes location at which to list files refresh : bool (=False) if False, look in local cache for file details first """ path = self._strip_protocol(path) if path in ['', '/']: return self._lsbuckets(refresh) else: return self._lsdir(path, refresh)
[docs] def exists(self, path): if path in ['', '/']: # the root always exists, even if anon return True bucket, key = self.split_path(path) if key: return super().exists(path) else: try: self.ls(path) return True except FileNotFoundError: return False
[docs] def touch(self, path, truncate=True, data=None, **kwargs): """Create empty file or truncate""" bucket, key = self.split_path(path) if not truncate and self.exists(path): raise ValueError("S3 does not support touching existent files") try: self._call_s3(self.s3.put_object, kwargs, Bucket=bucket, Key=key) except ClientError as ex: raise translate_boto_error(ex) self.invalidate_cache(self._parent(path))
[docs] def info(self, path, version_id=None): if path in ['/', '']: return {'name': path, 'size': 0, 'type': 'directory'} kwargs = self.kwargs.copy() if version_id is not None: if not self.version_aware: raise ValueError("version_id cannot be specified if the " "filesystem is not version aware") kwargs['VersionId'] = version_id if self.version_aware: try: bucket, key = self.split_path(path) out = self._call_s3(self.s3.head_object, kwargs, Bucket=bucket, Key=key, **self.req_kw) return { 'ETag': out['ETag'], 'Key': '/'.join([bucket, key]), 'LastModified': out['LastModified'], 'Size': out['ContentLength'], 'size': out['ContentLength'], 'path': '/'.join([bucket, key]), 'StorageClass': "STANDARD", 'VersionId': out.get('VersionId') } except ClientError as e: ee = translate_boto_error(e) # This could have failed since the thing we are looking for is a prefix. if isinstance(ee, FileNotFoundError): return super().info(path) else: raise ee except ParamValidationError as e: raise ValueError('Failed to head path %r: %s' % (path, e)) return super().info(path)
[docs] def isdir(self, path): path = self._strip_protocol(path).strip("/") # Send buckets to super if "/" not in path: return super(S3FileSystem, self).isdir(path) if path in self.dircache: for fp in self.dircache[path]: # For files the dircache can contain itself. # If it contains anything other than itself it is a directory. if fp["name"] != path: return True return False parent = self._parent(path) if parent in self.dircache: for f in self.dircache[parent]: if f["name"] == path: # If we find ourselves return whether we are a directory return f["type"] == "directory" return False # This only returns things within the path and NOT the path object itself return bool(self._lsdir(path))
[docs] def ls(self, path, detail=False, refresh=False, **kwargs): """ List single "directory" with or without details Parameters ---------- path : string/bytes location at which to list files detail : bool (=True) if True, each list item is a dict of file properties; otherwise, returns list of filenames refresh : bool (=False) if False, look in local cache for file details first kwargs : dict additional arguments passed on """ path = self._strip_protocol(path).rstrip('/') files = self._ls(path, refresh=refresh) if not files: files = self._ls(self._parent(path), refresh=refresh) files = [o for o in files if o['name'].rstrip('/') == path and o['type'] != 'directory'] if detail: return files else: return list(sorted(set([f['name'] for f in files])))
def object_version_info(self, path, **kwargs): if not self.version_aware: raise ValueError("version specific functionality is disabled for " "non-version aware filesystems") bucket, key = self.split_path(path) kwargs = {} out = {'IsTruncated': True} versions = [] while out['IsTruncated']: out = self._call_s3(self.s3.list_object_versions, kwargs, Bucket=bucket, Prefix=key, **self.req_kw) versions.extend(out['Versions']) kwargs['VersionIdMarker'] = out.get('NextVersionIdMarker', '') return versions _metadata_cache = {}
[docs] def metadata(self, path, refresh=False, **kwargs): """ Return metadata of path. Metadata is cached unless `refresh=True`. Parameters ---------- path : string/bytes filename to get metadata for refresh : bool (=False) if False, look in local cache for file metadata first """ bucket, key = self.split_path(path) if refresh or path not in self._metadata_cache: response = self._call_s3(self.s3.head_object, kwargs, Bucket=bucket, Key=key, **self.req_kw) self._metadata_cache[path] = response['Metadata'] return self._metadata_cache[path]
[docs] def get_tags(self, path): """Retrieve tag key/values for the given path Returns ------- {str: str} """ bucket, key = self.split_path(path) response = self._call_s3(self.s3.get_object_tagging, Bucket=bucket, Key=key) return {v['Key']: v['Value'] for v in response['TagSet']}
[docs] def put_tags(self, path, tags, mode='o'): """Set tags for given existing key Tags are a str:str mapping that can be attached to any key, see https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/allocation-tag-restrictions.html This is similar to, but distinct from, key metadata, which is usually set at key creation time. Parameters ---------- path: str Existing key to attach tags to tags: dict str, str Tags to apply. mode: One of 'o' or 'm' 'o': Will over-write any existing tags. 'm': Will merge in new tags with existing tags. Incurs two remote calls. """ bucket, key = self.split_path(path) if mode == 'm': existing_tags = self.get_tags(path=path) existing_tags.update(tags) new_tags = [{'Key': k, 'Value': v} for k, v in existing_tags.items()] elif mode == 'o': new_tags = [{'Key': k, 'Value': v} for k, v in tags.items()] else: raise ValueError("Mode must be {'o', 'm'}, not %s" % mode) tag = {'TagSet': new_tags} self._call_s3(self.s3.put_object_tagging, Bucket=bucket, Key=key, Tagging=tag)
[docs] def getxattr(self, path, attr_name, **kwargs): """ Get an attribute from the metadata. Examples -------- >>> mys3fs.getxattr('mykey', 'attribute_1') # doctest: +SKIP 'value_1' """ xattr = self.metadata(path, **kwargs) if attr_name in xattr: return xattr[attr_name] return None
[docs] def setxattr(self, path, copy_kwargs=None, **kw_args): """ Set metadata. Attributes have to be of the form documented in the `Metadata Reference`_. Parameters ---------- kw_args : key-value pairs like field="value", where the values must be strings. Does not alter existing fields, unless the field appears here - if the value is None, delete the field. copy_kwargs : dict, optional dictionary of additional params to use for the underlying s3.copy_object. Examples -------- >>> mys3file.setxattr(attribute_1='value1', attribute_2='value2') # doctest: +SKIP # Example for use with copy_args >>> mys3file.setxattr(copy_kwargs={'ContentType': 'application/pdf'}, ... attribute_1='value1') # doctest: +SKIP .. Metadata Reference: http://docs.aws.amazon.com/AmazonS3/latest/dev/UsingMetadata.html#object-metadata """ bucket, key = self.split_path(path) metadata = self.metadata(path) metadata.update(**kw_args) copy_kwargs = copy_kwargs or {} # remove all keys that are None for kw_key in kw_args: if kw_args[kw_key] is None: metadata.pop(kw_key, None) self._call_s3( self.s3.copy_object, copy_kwargs, CopySource="{}/{}".format(bucket, key), Bucket=bucket, Key=key, Metadata=metadata, MetadataDirective='REPLACE', ) # refresh metadata self._metadata_cache[path] = metadata
[docs] def chmod(self, path, acl, **kwargs): """ Set Access Control on a bucket/key See http://docs.aws.amazon.com/AmazonS3/latest/dev/acl-overview.html#canned-acl Parameters ---------- path : string the object to set acl : string the value of ACL to apply """ bucket, key = self.split_path(path) if key: if acl not in key_acls: raise ValueError('ACL not in %s', key_acls) self._call_s3(self.s3.put_object_acl, kwargs, Bucket=bucket, Key=key, ACL=acl) else: if acl not in buck_acls: raise ValueError('ACL not in %s', buck_acls) self._call_s3(self.s3.put_bucket_acl, kwargs, Bucket=bucket, ACL=acl)
[docs] def url(self, path, expires=3600, **kwargs): """ Generate presigned URL to access path by HTTP Parameters ---------- path : string the key path we are interested in expires : int the number of seconds this signature will be good for. """ bucket, key = self.split_path(path) return self.s3.generate_presigned_url( ClientMethod='get_object', Params=dict(Bucket=bucket, Key=key, **kwargs), ExpiresIn=expires)
[docs] def merge(self, path, filelist, **kwargs): """ Create single S3 file from list of S3 files Uses multi-part, no data is downloaded. The original files are not deleted. Parameters ---------- path : str The final file to produce filelist : list of str The paths, in order, to assemble into the final file. """ bucket, key = self.split_path(path) mpu = self._call_s3( self.s3.create_multipart_upload, kwargs, Bucket=bucket, Key=key ) out = [self._call_s3( self.s3.upload_part_copy, kwargs, Bucket=bucket, Key=key, UploadId=mpu['UploadId'], CopySource=f, PartNumber=i + 1) for (i, f) in enumerate(filelist)] parts = [{'PartNumber': i + 1, 'ETag': o['CopyPartResult']['ETag']} for (i, o) in enumerate(out)] part_info = {'Parts': parts} self.s3.complete_multipart_upload(Bucket=bucket, Key=key, UploadId=mpu['UploadId'], MultipartUpload=part_info) self.invalidate_cache(path)
[docs] def copy_basic(self, path1, path2, **kwargs): """ Copy file between locations on S3 """ buc1, key1 = self.split_path(path1) buc2, key2 = self.split_path(path2) try: self._call_s3( self.s3.copy_object, kwargs, Bucket=buc2, Key=key2, CopySource='/'.join([buc1, key1]) ) except ClientError as e: raise translate_boto_error(e) except ParamValidationError as e: raise ValueError('Copy failed (%r -> %r): %s' % (path1, path2, e))
def copy_managed(self, path1, path2, **kwargs): buc1, key1 = self.split_path(path1) buc2, key2 = self.split_path(path2) copy_source = { 'Bucket': buc1, 'Key': key1 } try: self.s3.copy( CopySource=copy_source, Bucket=buc2, Key=key2, ExtraArgs=self._get_s3_method_kwargs( self.s3.copy_object, kwargs ) ) except ClientError as e: raise translate_boto_error(e) except ParamValidationError as e: raise ValueError('Copy failed (%r -> %r): %s' % (path1, path2, e))
[docs] def copy(self, path1, path2, **kwargs): self.copy_managed(path1, path2, **kwargs) self.invalidate_cache(path2)
[docs] def bulk_delete(self, pathlist, **kwargs): """ Remove multiple keys with one call Parameters ---------- pathlist : listof strings The keys to remove, must all be in the same bucket. """ if not pathlist: return buckets = {self.split_path(path)[0] for path in pathlist} if len(buckets) > 1: raise ValueError("Bulk delete files should refer to only one " "bucket") bucket = buckets.pop() if len(pathlist) > 1000: for i in range((len(pathlist) // 1000) + 1): self.bulk_delete(pathlist[i * 1000:(i + 1) * 1000]) return delete_keys = {'Objects': [{'Key': self.split_path(path)[1]} for path in pathlist]} for path in pathlist: self.invalidate_cache(self._parent(path)) try: self._call_s3( self.s3.delete_objects, kwargs, Bucket=bucket, Delete=delete_keys) except ClientError as e: raise translate_boto_error(e)
[docs] def rm(self, path, recursive=False, **kwargs): """ Remove keys and/or bucket. Parameters ---------- path : string The location to remove. recursive : bool (True) Whether to remove also all entries below, i.e., which are returned by `walk()`. """ bucket, key = self.split_path(path) if recursive: files = self.find(path, maxdepth=None) if key and not files: raise FileNotFoundError(path) self.bulk_delete(files, **kwargs) if not key: self.rmdir(bucket) return if key: if not self.exists(path): raise FileNotFoundError(path) try: self._call_s3( self.s3.delete_object, kwargs, Bucket=bucket, Key=key) except ClientError as e: raise translate_boto_error(e) self.invalidate_cache(self._parent(path)) else: if self.exists(bucket): try: self.s3.delete_bucket(Bucket=bucket) except BotoCoreError as e: raise IOError('Delete bucket %r failed: %s' % (bucket, e)) self.invalidate_cache(bucket) self.invalidate_cache('') else: raise FileNotFoundError(path)
[docs] def invalidate_cache(self, path=None): if path is None: self.dircache.clear() else: path = self._strip_protocol(path) self.dircache.pop(path, None) self.dircache.pop(self._parent(path), None)
[docs] def walk(self, path, maxdepth=None, **kwargs): if path in ['', '*'] + [f'{p}://' for p in self.protocol]: raise ValueError('Cannot crawl all of S3') return super().walk(path, maxdepth=maxdepth, **kwargs)
[docs]class S3File(AbstractBufferedFile): """ Open S3 key as a file. Data is only loaded and cached on demand. Parameters ---------- s3 : S3FileSystem boto3 connection path : string S3 bucket/key to access mode : str One of 'rb', 'wb', 'ab'. These have the same meaning as they do for the built-in `open` function. block_size : int read-ahead size for finding delimiters fill_cache : bool If seeking to new a part of the file beyond the current buffer, with this True, the buffer will be filled between the sections to best support random access. When reading only a few specific chunks out of a file, performance may be better if False. acl: str Canned ACL to apply version_id : str Optional version to read the file at. If not specified this will default to the current version of the object. This is only used for reading. requester_pays : bool (False) If RequesterPays buckets are supported. Examples -------- >>> s3 = S3FileSystem() # doctest: +SKIP >>> with s3.open('my-bucket/my-file.txt', mode='rb') as f: # doctest: +SKIP ... ... # doctest: +SKIP See Also -------- S3FileSystem.open: used to create ``S3File`` objects """ retries = 5 part_min = 5 * 2 ** 20 part_max = 5 * 2 ** 30 def __init__(self, s3, path, mode='rb', block_size=5 * 2 ** 20, acl="", version_id=None, fill_cache=True, s3_additional_kwargs=None, autocommit=True, cache_type='bytes', requester_pays=False): bucket, key = s3.split_path(path) if not key: raise ValueError('Attempt to open non key-like path: %s' % path) self.bucket = bucket self.key = key self.version_id = version_id self.acl = acl if self.acl and self.acl not in key_acls: raise ValueError('ACL not in %s', key_acls) self.mpu = None self.parts = None self.fill_cache = fill_cache self.s3_additional_kwargs = s3_additional_kwargs or {} self.req_kw = {'RequestPayer': 'requester'} if requester_pays else {} super().__init__(s3, path, mode, block_size, autocommit=autocommit, cache_type=cache_type) self.s3 = self.fs # compatibility if self.writable(): if block_size < 5 * 2 ** 20: raise ValueError('Block size must be >=5MB') else: if version_id and self.fs.version_aware: self.version_id = version_id self.details = self.fs.info(self.path, version_id=version_id) self.size = self.details['size'] elif self.fs.version_aware: self.version_id = self.details.get('VersionId') # In this case we have not managed to get the VersionId out of details and # we should invalidate the cache and perform a full head_object since it # has likely been partially populated by ls. if self.version_id is None: self.fs.invalidate_cache(self.path) self.details = self.fs.info(self.path) self.version_id = self.details.get('VersionId') # when not using autocommit we want to have transactional state to manage self.append_block = False if 'a' in mode and s3.exists(path): loc = s3.info(path)['size'] if loc < 5 * 2 ** 20: # existing file too small for multi-upload: download self.write(self.fs.cat(self.path)) else: self.append_block = True self.loc = loc def _call_s3(self, method, *kwarglist, **kwargs): return self.fs._call_s3(method, self.s3_additional_kwargs, *kwarglist, **kwargs) def _initiate_upload(self): if self.autocommit and not self.append_block and self.tell() < self.blocksize: # only happens when closing small file, use on-shot PUT return logger.debug("Initiate upload for %s" % self) self.parts = [] try: self.mpu = self._call_s3( self.fs.s3.create_multipart_upload, Bucket=self.bucket, Key=self.key, ACL=self.acl) except ClientError as e: raise translate_boto_error(e) except ParamValidationError as e: raise ValueError('Initiating write to %r failed: %s' % (self.path, e)) if self.append_block: # use existing data in key when appending, # and block is big enough out = self.fs._call_s3( self.fs.s3.upload_part_copy, self.s3_additional_kwargs, Bucket=self.bucket, Key=self.key, PartNumber=1, UploadId=self.mpu['UploadId'], CopySource=self.path) self.parts.append({'PartNumber': 1, 'ETag': out['CopyPartResult']['ETag']})
[docs] def metadata(self, refresh=False, **kwargs): """ Return metadata of file. See :func:`~s3fs.S3Filesystem.metadata`. Metadata is cached unless `refresh=True`. """ return self.fs.metadata(self.path, refresh, **kwargs)
[docs] def getxattr(self, xattr_name, **kwargs): """ Get an attribute from the metadata. See :func:`~s3fs.S3Filesystem.getxattr`. Examples -------- >>> mys3file.getxattr('attribute_1') # doctest: +SKIP 'value_1' """ return self.fs.getxattr(self.path, xattr_name, **kwargs)
[docs] def setxattr(self, copy_kwargs=None, **kwargs): """ Set metadata. See :func:`~s3fs.S3Filesystem.setxattr`. Examples -------- >>> mys3file.setxattr(attribute_1='value1', attribute_2='value2') # doctest: +SKIP """ if self.writable(): raise NotImplementedError('cannot update metadata while file ' 'is open for writing') return self.fs.setxattr(self.path, copy_kwargs=copy_kwargs, **kwargs)
[docs] def url(self, **kwargs): """ HTTP URL to read this file (if it already exists) """ return self.fs.url(self.path, **kwargs)
def _fetch_range(self, start, end): return _fetch_range(self.fs.s3, self.bucket, self.key, self.version_id, start, end, req_kw=self.req_kw) def _upload_chunk(self, final=False): bucket, key = self.s3.split_path(self.path) logger.debug("Upload for %s, final=%s, loc=%s, buffer loc=%s" % ( self, final, self.loc, self.buffer.tell() )) if self.autocommit and not self.append_block and final and self.tell() < self.blocksize: # only happens when closing small file, use on-shot PUT data1 = False else: self.buffer.seek(0) (data0, data1) = (None, self.buffer.read(self.blocksize)) while data1: (data0, data1) = (data1, self.buffer.read(self.blocksize)) data1_size = len(data1) if 0 < data1_size < self.blocksize: remainder = data0 + data1 remainder_size = self.blocksize + data1_size if remainder_size <= self.part_max: (data0, data1) = (remainder, None) else: partition = remainder_size // 2 (data0, data1) = (remainder[:partition], remainder[partition:]) part = len(self.parts) + 1 logger.debug("Upload chunk %s, %s" % (self, part)) for attempt in range(self.retries + 1): try: out = self._call_s3( self.fs.s3.upload_part, Bucket=bucket, PartNumber=part, UploadId=self.mpu['UploadId'], Body=data0, Key=key) break except S3_RETRYABLE_ERRORS as exc: if attempt < self.retries: logger.debug('Exception %r on S3 write, retrying', exc, exc_info=True) time.sleep(1.7**attempt * 0.1) except Exception as exc: raise IOError('Write failed: %r' % exc) else: raise IOError('Write failed after %i retries' % self.retries) self.parts.append({'PartNumber': part, 'ETag': out['ETag']}) if self.autocommit and final: self.commit() return not final
[docs] def commit(self): logger.debug("Commit %s" % self) if self.tell() == 0: if self.buffer is not None: logger.debug("Empty file committed %s" % self) self._abort_mpu() self.fs.touch(self.path) elif not self.parts: if self.buffer is not None: logger.debug("One-shot upload of %s" % self) self.buffer.seek(0) data = self.buffer.read() self._call_s3( self.fs.s3.put_object, Key=self.key, Bucket=self.bucket, Body=data, **self.kwargs ) else: raise RuntimeError else: logger.debug("Complete multi-part upload for %s " % self) part_info = {'Parts': self.parts} write_result = self._call_s3( self.fs.s3.complete_multipart_upload, Bucket=self.bucket, Key=self.key, UploadId=self.mpu['UploadId'], MultipartUpload=part_info) if self.fs.version_aware: self.version_id = write_result.get('VersionId') # complex cache invalidation, since file's appearance can cause several # directories self.buffer = None parts = self.path.split('/') path = parts[0] for p in parts[1:]: if path in self.fs.dircache and not [ True for f in self.fs.dircache[path] if f['name'] == path + '/' + p]: self.fs.invalidate_cache(path) path = path + '/' + p
[docs] def discard(self): self._abort_mpu() self.buffer = None # file becomes unusable
def _abort_mpu(self): if self.mpu: self._call_s3( self.fs.s3.abort_multipart_upload, Bucket=self.bucket, Key=self.key, UploadId=self.mpu['UploadId'], ) self.mpu = None
def _fetch_range(client, bucket, key, version_id, start, end, max_attempts=10, req_kw=None): if req_kw is None: req_kw = {} if start == end: # When these match, we would make a request with `range=start-end - 1` # According to RFC2616, servers are supposed to ignore the Range # field when it's invalid like this. S3 does ignore it, moto doesn't. # To avoid differences in behavior under mocking, we just avoid # making these requests. It's hoped that since we're being called # from a caching object, this won't end up mattering. logger.debug( 'skip fetch for negative range - bucket=%s,key=%s,start=%d,end=%d', bucket, key, start, end ) return b'' logger.debug("Fetch: %s/%s, %s-%s", bucket, key, start, end) for i in range(max_attempts): try: if version_id is not None: kwargs = dict({'VersionId': version_id}, **req_kw) else: kwargs = req_kw resp = client.get_object(Bucket=bucket, Key=key, Range='bytes=%i-%i' % (start, end - 1), **kwargs) return resp['Body'].read() except S3_RETRYABLE_ERRORS as e: logger.debug('Exception %r on S3 download, retrying', e, exc_info=True) time.sleep(1.7**i * 0.1) continue except ConnectionError as e: logger.debug('ConnectionError %r on S3 download, retrying', e, exc_info=True) time.sleep(1.7**i * 0.1) continue except ClientError as e: if e.response['Error'].get('Code', 'Unknown') in ['416', 'InvalidRange']: return b'' raise translate_boto_error(e) except Exception as e: if 'time' in str(e).lower(): # Actual exception type changes often continue else: raise raise RuntimeError("Max number of S3 retries exceeded")