Source code for apache_beam.io.azure.blobstorageio

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"""Azure Blob Storage client.
"""

# pytype: skip-file

import errno
import io
import logging
import os
import re
import tempfile
import time

from apache_beam.io.filesystemio import Downloader
from apache_beam.io.filesystemio import DownloaderStream
from apache_beam.io.filesystemio import Uploader
from apache_beam.io.filesystemio import UploaderStream
from apache_beam.utils import retry

_LOGGER = logging.getLogger(__name__)

try:
  # pylint: disable=wrong-import-order, wrong-import-position
  # pylint: disable=ungrouped-imports
  from azure.core.exceptions import ResourceNotFoundError
  from azure.storage.blob import (
      BlobServiceClient,
      ContentSettings,
  )
  AZURE_DEPS_INSTALLED = True
except ImportError:
  AZURE_DEPS_INSTALLED = False

DEFAULT_READ_BUFFER_SIZE = 16 * 1024 * 1024

MAX_BATCH_OPERATION_SIZE = 100


[docs]def parse_azfs_path(azfs_path, blob_optional=False, get_account=False): """Return the storage account, the container and blob names of the given azfs:// path. """ match = re.match( '^azfs://([a-z0-9]{3,24})/([a-z0-9](?![a-z0-9-]*--[a-z0-9-]*)' '[a-z0-9-]{1,61}[a-z0-9])/(.*)$', azfs_path) if match is None or (match.group(3) == '' and not blob_optional): raise ValueError( 'Azure Blob Storage path must be in the form ' 'azfs://<storage-account>/<container>/<path>.') result = None if get_account: result = match.group(1), match.group(2), match.group(3) else: result = match.group(2), match.group(3) return result
[docs]def get_azfs_url(storage_account, container, blob=''): """Returns the url in the form of https://account.blob.core.windows.net/container/blob-name """ return 'https://' + storage_account + '.blob.core.windows.net/' + \ container + '/' + blob
[docs]class Blob(): """A Blob in Azure Blob Storage.""" def __init__(self, etag, name, last_updated, size, mime_type): self.etag = etag self.name = name self.last_updated = last_updated self.size = size self.mime_type = mime_type
[docs]class BlobStorageIOError(IOError, retry.PermanentException): """Blob Strorage IO error that should not be retried.""" pass
[docs]class BlobStorageError(Exception): """Blob Storage client error.""" def __init__(self, message=None, code=None): self.message = message self.code = code
[docs]class BlobStorageIO(object): """Azure Blob Storage I/O client.""" def __init__(self, client=None): connect_str = os.getenv('AZURE_STORAGE_CONNECTION_STRING') if client is None: self.client = BlobServiceClient.from_connection_string(connect_str) else: self.client = client if not AZURE_DEPS_INSTALLED: raise RuntimeError('Azure dependencies are not installed. Unable to run.')
[docs] def open( self, filename, mode='r', read_buffer_size=DEFAULT_READ_BUFFER_SIZE, mime_type='application/octet-stream'): """Open an Azure Blob Storage file path for reading or writing. Args: filename (str): Azure Blob Storage file path in the form ``azfs://<storage-account>/<container>/<path>``. mode (str): ``'r'`` for reading or ``'w'`` for writing. read_buffer_size (int): Buffer size to use during read operations. mime_type (str): Mime type to set for write operations. Returns: Azure Blob Storage file object. Raises: ValueError: Invalid open file mode. """ if mode == 'r' or mode == 'rb': downloader = BlobStorageDownloader( self.client, filename, buffer_size=read_buffer_size) return io.BufferedReader( DownloaderStream( downloader, read_buffer_size=read_buffer_size, mode=mode), buffer_size=read_buffer_size) elif mode == 'w' or mode == 'wb': uploader = BlobStorageUploader(self.client, filename, mime_type) return io.BufferedWriter( UploaderStream(uploader, mode=mode), buffer_size=128 * 1024) else: raise ValueError('Invalid file open mode: %s.' % mode)
[docs] @retry.with_exponential_backoff( retry_filter=retry.retry_on_beam_io_error_filter) def copy(self, src, dest): """Copies a single Azure Blob Storage blob from src to dest. Args: src: Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. dest: Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. Raises: TimeoutError: on timeout. """ src_storage_account, src_container, src_blob = parse_azfs_path( src, get_account=True) dest_container, dest_blob = parse_azfs_path(dest) source_blob = get_azfs_url(src_storage_account, src_container, src_blob) copied_blob = self.client.get_blob_client(dest_container, dest_blob) try: copied_blob.start_copy_from_url(source_blob) except ResourceNotFoundError as e: message = e.reason code = e.status_code raise BlobStorageError(message, code)
# We intentionally do not decorate this method with a retry, since the # underlying copy operation is already an idempotent operation protected # by retry decorators.
[docs] def copy_tree(self, src, dest): """Renames the given Azure Blob storage directory and its contents recursively from src to dest. Args: src: Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. dest: Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. Returns: List of tuples of (src, dest, exception) where exception is None if the operation succeeded or the relevant exception if the operation failed. """ assert src.endswith('/') assert dest.endswith('/') results = [] for entry in self.list_prefix(src): rel_path = entry[len(src):] try: self.copy(entry, dest + rel_path) results.append((entry, dest + rel_path, None)) except BlobStorageError as e: results.append((entry, dest + rel_path, e)) return results
# We intentionally do not decorate this method with a retry, since the # underlying copy operation is already an idempotent operation protected # by retry decorators.
[docs] def copy_paths(self, src_dest_pairs): """Copies the given Azure Blob Storage blobs from src to dest. This can handle directory or file paths. Args: src_dest_pairs: List of (src, dest) tuples of azfs://<storage-account>/<container>/[name] file paths to copy from src to dest. Returns: List of tuples of (src, dest, exception) in the same order as the src_dest_pairs argument, where exception is None if the operation succeeded or the relevant exception if the operation failed. """ if not src_dest_pairs: return [] results = [] for src_path, dest_path in src_dest_pairs: # Case 1. They are directories. if src_path.endswith('/') and dest_path.endswith('/'): try: results += self.copy_tree(src_path, dest_path) except BlobStorageError as e: results.append((src_path, dest_path, e)) # Case 2. They are individual blobs. elif not src_path.endswith('/') and not dest_path.endswith('/'): try: self.copy(src_path, dest_path) results.append((src_path, dest_path, None)) except BlobStorageError as e: results.append((src_path, dest_path, e)) # Mismatched paths (one directory, one non-directory) get an error. else: e = BlobStorageError( "Unable to copy mismatched paths" + "(directory, non-directory): %s, %s" % (src_path, dest_path), 400) results.append((src_path, dest_path, e)) return results
# We intentionally do not decorate this method with a retry, since the # underlying copy and delete operations are already idempotent operations # protected by retry decorators.
[docs] def rename(self, src, dest): """Renames the given Azure Blob Storage blob from src to dest. Args: src: Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. dest: Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. """ self.copy(src, dest) self.delete(src)
# We intentionally do not decorate this method with a retry, since the # underlying copy and delete operations are already idempotent operations # protected by retry decorators.
[docs] def rename_files(self, src_dest_pairs): """Renames the given Azure Blob Storage blobs from src to dest. Args: src_dest_pairs: List of (src, dest) tuples of azfs://<storage-account>/<container>/[name] file paths to rename from src to dest. Returns: List of tuples of (src, dest, exception) in the same order as the src_dest_pairs argument, where exception is None if the operation succeeded or the relevant exception if the operation failed. """ if not src_dest_pairs: return [] for src, dest in src_dest_pairs: if src.endswith('/') or dest.endswith('/'): raise ValueError('Unable to rename a directory.') # Results from copy operation. copy_results = self.copy_paths(src_dest_pairs) paths_to_delete = \ [src for (src, _, error) in copy_results if error is None] # Results from delete operation. delete_results = self.delete_files(paths_to_delete) # Get rename file results (list of tuples). results = [] # Using a dictionary will make the operation faster. delete_results_dict = {src: error for (src, error) in delete_results} for src, dest, error in copy_results: # If there was an error in the copy operation. if error is not None: results.append((src, dest, error)) # If there was an error in the delete operation. elif delete_results_dict[src] is not None: results.append((src, dest, delete_results_dict[src])) # If there was no error in the operations. else: results.append((src, dest, None)) return results
[docs] def exists(self, path): """Returns whether the given Azure Blob Storage blob exists. Args: path: Azure Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. """ try: self._blob_properties(path) return True except ResourceNotFoundError as e: if e.status_code == 404: # HTTP 404 indicates that the file did not exist. return False else: # We re-raise all other exceptions. raise
[docs] def size(self, path): """Returns the size of a single Blob Storage blob. This method does not perform glob expansion. Hence the given path must be for a single Blob Storage blob. Returns: size of the Blob Storage blob in bytes. """ return self._blob_properties(path).size
[docs] def last_updated(self, path): """Returns the last updated epoch time of a single Azure Blob Storage blob. This method does not perform glob expansion. Hence the given path must be for a single Azure Blob Storage blob. Returns: last updated time of the Azure Blob Storage blob in seconds. """ return self._updated_to_seconds(self._blob_properties(path).last_modified)
[docs] def checksum(self, path): """Looks up the checksum of an Azure Blob Storage blob. Args: path: Azure Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. """ return self._blob_properties(path).properties.etag
def _status(self, path): """For internal use only; no backwards-compatibility guarantees. Returns supported fields (checksum, last_updated, size) of a single object as a dict at once. This method does not perform glob expansion. Hence the given path must be for a single blob property. Returns: dict of fields of the blob property. """ properties = self._blob_properties(path) file_status = {} if hasattr(properties, 'etag'): file_status['checksum'] = properties.etag if hasattr(properties, 'last_modified'): file_status['last_updated'] = self._updated_to_seconds( properties.last_modified) if hasattr(properties, 'size'): file_status['size'] = properties.size return file_status @retry.with_exponential_backoff( retry_filter=retry.retry_on_beam_io_error_filter) def _blob_properties(self, path): """Returns a blob properties object for the given path This method does not perform glob expansion. Hence the given path must be for a single blob properties object. Returns: blob properties. """ container, blob = parse_azfs_path(path) blob_to_check = self.client.get_blob_client(container, blob) try: properties = blob_to_check.get_blob_properties() except ResourceNotFoundError as e: message = e.reason code = e.status_code raise BlobStorageError(message, code) return properties @staticmethod def _updated_to_seconds(updated): """Helper function transform the updated field of response to seconds""" return ( time.mktime(updated.timetuple()) - time.timezone + updated.microsecond / 1000000.0)
[docs] @retry.with_exponential_backoff( retry_filter=retry.retry_on_beam_io_error_filter) def delete(self, path): """Deletes a single blob at the given Azure Blob Storage path. Args: path: Azure Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. """ container, blob = parse_azfs_path(path) blob_to_delete = self.client.get_blob_client(container, blob) try: blob_to_delete.delete_blob() except ResourceNotFoundError as e: if e.status_code == 404: # Return success when the file doesn't exist anymore for idempotency. return else: logging.error('HTTP error while deleting file %s', path) raise e
# We intentionally do not decorate this method with a retry, since the # underlying copy and delete operations are already idempotent operations # protected by retry decorators.
[docs] def delete_paths(self, paths): """Deletes the given Azure Blob Storage blobs from src to dest. This can handle directory or file paths. Args: paths: list of Azure Blob Storage paths in the form azfs://<storage-account>/<container>/[name] that give the file blobs to be deleted. Returns: List of tuples of (src, dest, exception) in the same order as the src_dest_pairs argument, where exception is None if the operation succeeded or the relevant exception if the operation failed. """ directories, blobs = [], [] # Retrieve directories and not directories. for path in paths: if path.endswith('/'): directories.append(path) else: blobs.append(path) results = {} for directory in directories: directory_result = dict(self.delete_tree(directory)) results.update(directory_result) blobs_results = dict(self.delete_files(blobs)) results.update(blobs_results) return results
# We intentionally do not decorate this method with a retry, since the # underlying copy and delete operations are already idempotent operations # protected by retry decorators.
[docs] def delete_tree(self, root): """Deletes all blobs under the given Azure BlobStorage virtual directory. Args: path: Azure Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name] (ending with a "/"). Returns: List of tuples of (path, exception), where each path is a blob under the given root. exception is None if the operation succeeded or the relevant exception if the operation failed. """ assert root.endswith('/') # Get the blob under the root directory. paths_to_delete = self.list_prefix(root) return self.delete_files(paths_to_delete)
# We intentionally do not decorate this method with a retry, since the # underlying copy and delete operations are already idempotent operations # protected by retry decorators.
[docs] def delete_files(self, paths): """Deletes the given Azure Blob Storage blobs from src to dest. Args: paths: list of Azure Blob Storage paths in the form azfs://<storage-account>/<container>/[name] that give the file blobs to be deleted. Returns: List of tuples of (src, dest, exception) in the same order as the src_dest_pairs argument, where exception is None if the operation succeeded or the relevant exception if the operation failed. """ if not paths: return [] # Group blobs into containers. containers, blobs = zip(*[parse_azfs_path(path, get_account=False) \ for path in paths]) grouped_blobs = {container: [] for container in containers} # Fill dictionary. for container, blob in zip(containers, blobs): grouped_blobs[container].append(blob) results = {} # Delete minibatches of blobs for each container. for container, blobs in grouped_blobs.items(): for i in range(0, len(blobs), MAX_BATCH_OPERATION_SIZE): blobs_to_delete = blobs[i:i + MAX_BATCH_OPERATION_SIZE] results.update(self._delete_batch(container, blobs_to_delete)) final_results = \ [(path, results[parse_azfs_path(path, get_account=False)]) \ for path in paths] return final_results
@retry.with_exponential_backoff( retry_filter=retry.retry_on_beam_io_error_filter) def _delete_batch(self, container, blobs): """A helper method. Azure Blob Storage Python Client allows batch deletions for blobs within the same container. Args: container: container name. blobs: list of blobs to be deleted. Returns: Dictionary of the form {(container, blob): error}, where error is None if the operation succeeded. """ container_client = self.client.get_container_client(container) results = {} for blob in blobs: try: response = container_client.delete_blob(blob) results[(container, blob)] = response except ResourceNotFoundError as e: results[(container, blob)] = e.status_code return results
[docs] @retry.with_exponential_backoff( retry_filter=retry.retry_on_beam_io_error_filter) def list_prefix(self, path, with_metadata=False): """Lists files matching the prefix. Args: path: Azure Blob Storage file path pattern in the form azfs://<storage-account>/<container>/[name]. with_metadata: Experimental. Specify whether returns file metadata. Returns: If ``with_metadata`` is False: dict of file name -> size; if ``with_metadata`` is True: dict of file name -> tuple(size, timestamp). """ storage_account, container, blob = parse_azfs_path( path, blob_optional=True, get_account=True) file_info = {} counter = 0 start_time = time.time() if with_metadata: logging.debug("Starting the file information of the input") else: logging.debug("Starting the size estimation of the input") container_client = self.client.get_container_client(container) while True: response = container_client.list_blobs(name_starts_with=blob) for item in response: file_name = "azfs://%s/%s/%s" % (storage_account, container, item.name) if with_metadata: file_info[file_name] = ( item.size, self._updated_to_seconds(item.last_modified)) else: file_info[file_name] = item.size counter += 1 if counter % 10000 == 0: if with_metadata: logging.info( "Finished computing file information of: %s files", len(file_info)) else: logging.info("Finished computing size of: %s files", len(file_info)) break logging.log( # do not spam logs when list_prefix is likely used to check empty folder logging.INFO if counter > 0 else logging.DEBUG, "Finished listing %s files in %s seconds.", counter, time.time() - start_time) return file_info
[docs]class BlobStorageDownloader(Downloader): def __init__(self, client, path, buffer_size): self._client = client self._path = path self._container, self._blob = parse_azfs_path(path) self._buffer_size = buffer_size self._blob_to_download = self._client.get_blob_client( self._container, self._blob) try: properties = self._get_object_properties() except ResourceNotFoundError as http_error: if http_error.status_code == 404: raise IOError(errno.ENOENT, 'Not found: %s' % self._path) else: _LOGGER.error( 'HTTP error while requesting file %s: %s', self._path, http_error) raise self._size = properties.size @retry.with_exponential_backoff( retry_filter=retry.retry_on_beam_io_error_filter) def _get_object_properties(self): return self._blob_to_download.get_blob_properties() @property def size(self): return self._size
[docs] def get_range(self, start, end): # Download_blob first parameter is offset and second is length (exclusive). blob_data = self._blob_to_download.download_blob(start, end - start) # Returns the content as bytes. return blob_data.readall()
[docs]class BlobStorageUploader(Uploader): def __init__(self, client, path, mime_type='application/octet-stream'): self._client = client self._path = path self._container, self._blob = parse_azfs_path(path) self._content_settings = ContentSettings(mime_type) self._blob_to_upload = self._client.get_blob_client( self._container, self._blob) # Temporary file. self._temporary_file = tempfile.NamedTemporaryFile()
[docs] def put(self, data): self._temporary_file.write(data.tobytes())
[docs] def finish(self): self._temporary_file.seek(0) # The temporary file is deleted immediately after the operation. with open(self._temporary_file.name, "rb") as f: self._blob_to_upload.upload_blob( f.read(), overwrite=True, content_settings=self._content_settings)