| Index: tools/telemetry/third_party/gsutilz/gslib/daisy_chain_wrapper.py
|
| diff --git a/tools/telemetry/third_party/gsutilz/gslib/daisy_chain_wrapper.py b/tools/telemetry/third_party/gsutilz/gslib/daisy_chain_wrapper.py
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| deleted file mode 100644
|
| index 4e5717df8077b8fe1e8e89d58468da3e082c1eb6..0000000000000000000000000000000000000000
|
| --- a/tools/telemetry/third_party/gsutilz/gslib/daisy_chain_wrapper.py
|
| +++ /dev/null
|
| @@ -1,282 +0,0 @@
|
| -# -*- coding: utf-8 -*-
|
| -# Copyright 2014 Google Inc. All Rights Reserved.
|
| -#
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| -# Licensed under the Apache License, Version 2.0 (the "License");
|
| -# you may not use this file except in compliance with the License.
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| -# You may obtain a copy of the License at
|
| -#
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| -# http://www.apache.org/licenses/LICENSE-2.0
|
| -#
|
| -# Unless required by applicable law or agreed to in writing, software
|
| -# distributed under the License is distributed on an "AS IS" BASIS,
|
| -# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
| -# See the License for the specific language governing permissions and
|
| -# limitations under the License.
|
| -"""Wrapper for use in daisy-chained copies."""
|
| -
|
| -from collections import deque
|
| -import os
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| -import threading
|
| -import time
|
| -
|
| -from gslib.cloud_api import BadRequestException
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| -from gslib.cloud_api import CloudApi
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| -from gslib.util import CreateLock
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| -from gslib.util import TRANSFER_BUFFER_SIZE
|
| -
|
| -
|
| -# This controls the amount of bytes downloaded per download request.
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| -# We do not buffer this many bytes in memory at a time - that is controlled by
|
| -# DaisyChainWrapper.max_buffer_size. This is the upper bound of bytes that may
|
| -# be unnecessarily downloaded if there is a break in the resumable upload.
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| -_DEFAULT_DOWNLOAD_CHUNK_SIZE = 1024*1024*100
|
| -
|
| -
|
| -class BufferWrapper(object):
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| - """Wraps the download file pointer to use our in-memory buffer."""
|
| -
|
| - def __init__(self, daisy_chain_wrapper):
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| - """Provides a buffered write interface for a file download.
|
| -
|
| - Args:
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| - daisy_chain_wrapper: DaisyChainWrapper instance to use for buffer and
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| - locking.
|
| - """
|
| - self.daisy_chain_wrapper = daisy_chain_wrapper
|
| -
|
| - def write(self, data): # pylint: disable=invalid-name
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| - """Waits for space in the buffer, then writes data to the buffer."""
|
| - while True:
|
| - with self.daisy_chain_wrapper.lock:
|
| - if (self.daisy_chain_wrapper.bytes_buffered <
|
| - self.daisy_chain_wrapper.max_buffer_size):
|
| - break
|
| - # Buffer was full, yield thread priority so the upload can pull from it.
|
| - time.sleep(0)
|
| - data_len = len(data)
|
| - if data_len:
|
| - with self.daisy_chain_wrapper.lock:
|
| - self.daisy_chain_wrapper.buffer.append(data)
|
| - self.daisy_chain_wrapper.bytes_buffered += data_len
|
| -
|
| -
|
| -class DaisyChainWrapper(object):
|
| - """Wrapper class for daisy-chaining a cloud download to an upload.
|
| -
|
| - This class instantiates a BufferWrapper object to buffer the download into
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| - memory, consuming a maximum of max_buffer_size. It implements intelligent
|
| - behavior around read and seek that allow for all of the operations necessary
|
| - to copy a file.
|
| -
|
| - This class is coupled with the XML and JSON implementations in that it
|
| - expects that small buffers (maximum of TRANSFER_BUFFER_SIZE) in size will be
|
| - used.
|
| - """
|
| -
|
| - def __init__(self, src_url, src_obj_size, gsutil_api, progress_callback=None,
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| - download_chunk_size=_DEFAULT_DOWNLOAD_CHUNK_SIZE):
|
| - """Initializes the daisy chain wrapper.
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| -
|
| - Args:
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| - src_url: Source CloudUrl to copy from.
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| - src_obj_size: Size of source object.
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| - gsutil_api: gsutil Cloud API to use for the copy.
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| - progress_callback: Optional callback function for progress notifications
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| - for the download thread. Receives calls with arguments
|
| - (bytes_transferred, total_size).
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| - download_chunk_size: Integer number of bytes to download per
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| - GetObjectMedia request. This is the upper bound of bytes that may be
|
| - unnecessarily downloaded if there is a break in the resumable upload.
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| -
|
| - """
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| - # Current read position for the upload file pointer.
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| - self.position = 0
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| - self.buffer = deque()
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| -
|
| - self.bytes_buffered = 0
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| - # Maximum amount of bytes in memory at a time.
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| - self.max_buffer_size = 1024 * 1024 # 1 MiB
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| -
|
| - self._download_chunk_size = download_chunk_size
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| -
|
| - # We save one buffer's worth of data as a special case for boto,
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| - # which seeks back one buffer and rereads to compute hashes. This is
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| - # unnecessary because we can just compare cloud hash digests at the end,
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| - # but it allows this to work without modfiying boto.
|
| - self.last_position = 0
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| - self.last_data = None
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| -
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| - # Protects buffer, position, bytes_buffered, last_position, and last_data.
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| - self.lock = CreateLock()
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| -
|
| - # Protects download_exception.
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| - self.download_exception_lock = CreateLock()
|
| -
|
| - self.src_obj_size = src_obj_size
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| - self.src_url = src_url
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| -
|
| - # This is safe to use the upload and download thread because the download
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| - # thread calls only GetObjectMedia, which creates a new HTTP connection
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| - # independent of gsutil_api. Thus, it will not share an HTTP connection
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| - # with the upload.
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| - self.gsutil_api = gsutil_api
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| -
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| - # If self.download_thread dies due to an exception, it is saved here so
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| - # that it can also be raised in the upload thread.
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| - self.download_exception = None
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| - self.download_thread = None
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| - self.progress_callback = progress_callback
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| - self.stop_download = threading.Event()
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| - self.StartDownloadThread(progress_callback=self.progress_callback)
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| -
|
| - def StartDownloadThread(self, start_byte=0, progress_callback=None):
|
| - """Starts the download thread for the source object (from start_byte)."""
|
| -
|
| - def PerformDownload(start_byte, progress_callback):
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| - """Downloads the source object in chunks.
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| -
|
| - This function checks the stop_download event and exits early if it is set.
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| - It should be set when there is an error during the daisy-chain upload,
|
| - then this function can be called again with the upload's current position
|
| - as start_byte.
|
| -
|
| - Args:
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| - start_byte: Byte from which to begin the download.
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| - progress_callback: Optional callback function for progress
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| - notifications. Receives calls with arguments
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| - (bytes_transferred, total_size).
|
| - """
|
| - # TODO: Support resumable downloads. This would require the BufferWrapper
|
| - # object to support seek() and tell() which requires coordination with
|
| - # the upload.
|
| - try:
|
| - while start_byte + self._download_chunk_size < self.src_obj_size:
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| - self.gsutil_api.GetObjectMedia(
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| - self.src_url.bucket_name, self.src_url.object_name,
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| - BufferWrapper(self), start_byte=start_byte,
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| - end_byte=start_byte + self._download_chunk_size - 1,
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| - generation=self.src_url.generation, object_size=self.src_obj_size,
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| - download_strategy=CloudApi.DownloadStrategy.ONE_SHOT,
|
| - provider=self.src_url.scheme, progress_callback=progress_callback)
|
| - if self.stop_download.is_set():
|
| - # Download thread needs to be restarted, so exit.
|
| - self.stop_download.clear()
|
| - return
|
| - start_byte += self._download_chunk_size
|
| - self.gsutil_api.GetObjectMedia(
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| - self.src_url.bucket_name, self.src_url.object_name,
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| - BufferWrapper(self), start_byte=start_byte,
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| - generation=self.src_url.generation, object_size=self.src_obj_size,
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| - download_strategy=CloudApi.DownloadStrategy.ONE_SHOT,
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| - provider=self.src_url.scheme, progress_callback=progress_callback)
|
| - # We catch all exceptions here because we want to store them.
|
| - except Exception, e: # pylint: disable=broad-except
|
| - # Save the exception so that it can be seen in the upload thread.
|
| - with self.download_exception_lock:
|
| - self.download_exception = e
|
| - raise
|
| -
|
| - # TODO: If we do gzip encoding transforms mid-transfer, this will fail.
|
| - self.download_thread = threading.Thread(
|
| - target=PerformDownload,
|
| - args=(start_byte, progress_callback))
|
| - self.download_thread.start()
|
| -
|
| - def read(self, amt=None): # pylint: disable=invalid-name
|
| - """Exposes a stream from the in-memory buffer to the upload."""
|
| - if self.position == self.src_obj_size or amt == 0:
|
| - # If there is no data left or 0 bytes were requested, return an empty
|
| - # string so callers can call still call len() and read(0).
|
| - return ''
|
| - if amt is None or amt > TRANSFER_BUFFER_SIZE:
|
| - raise BadRequestException(
|
| - 'Invalid HTTP read size %s during daisy chain operation, '
|
| - 'expected <= %s.' % (amt, TRANSFER_BUFFER_SIZE))
|
| -
|
| - while True:
|
| - with self.lock:
|
| - if self.buffer:
|
| - break
|
| - with self.download_exception_lock:
|
| - if self.download_exception:
|
| - # Download thread died, so we will never recover. Raise the
|
| - # exception that killed it.
|
| - raise self.download_exception # pylint: disable=raising-bad-type
|
| - # Buffer was empty, yield thread priority so the download thread can fill.
|
| - time.sleep(0)
|
| - with self.lock:
|
| - # TODO: Need to handle the caller requesting less than a
|
| - # transfer_buffer_size worth of data.
|
| - data = self.buffer.popleft()
|
| - self.last_position = self.position
|
| - self.last_data = data
|
| - data_len = len(data)
|
| - self.position += data_len
|
| - self.bytes_buffered -= data_len
|
| - if data_len > amt:
|
| - raise BadRequestException(
|
| - 'Invalid read during daisy chain operation, got data of size '
|
| - '%s, expected size %s.' % (data_len, amt))
|
| - return data
|
| -
|
| - def tell(self): # pylint: disable=invalid-name
|
| - with self.lock:
|
| - return self.position
|
| -
|
| - def seek(self, offset, whence=os.SEEK_SET): # pylint: disable=invalid-name
|
| - restart_download = False
|
| - if whence == os.SEEK_END:
|
| - if offset:
|
| - raise IOError(
|
| - 'Invalid seek during daisy chain operation. Non-zero offset %s '
|
| - 'from os.SEEK_END is not supported' % offset)
|
| - with self.lock:
|
| - self.last_position = self.position
|
| - self.last_data = None
|
| - # Safe because we check position against src_obj_size in read.
|
| - self.position = self.src_obj_size
|
| - elif whence == os.SEEK_SET:
|
| - with self.lock:
|
| - if offset == self.position:
|
| - pass
|
| - elif offset == self.last_position:
|
| - self.position = self.last_position
|
| - if self.last_data:
|
| - # If we seek to end and then back, we won't have last_data; we'll
|
| - # get it on the next call to read.
|
| - self.buffer.appendleft(self.last_data)
|
| - self.bytes_buffered += len(self.last_data)
|
| - else:
|
| - # Once a download is complete, boto seeks to 0 and re-reads to
|
| - # compute the hash if an md5 isn't already present (for example a GCS
|
| - # composite object), so we have to re-download the whole object.
|
| - # Also, when daisy-chaining to a resumable upload, on error the
|
| - # service may have received any number of the bytes; the download
|
| - # needs to be restarted from that point.
|
| - restart_download = True
|
| -
|
| - if restart_download:
|
| - self.stop_download.set()
|
| -
|
| - # Consume any remaining bytes in the download thread so that
|
| - # the thread can exit, then restart the thread at the desired position.
|
| - while self.download_thread.is_alive():
|
| - with self.lock:
|
| - while self.bytes_buffered:
|
| - self.bytes_buffered -= len(self.buffer.popleft())
|
| - time.sleep(0)
|
| -
|
| - with self.lock:
|
| - self.position = offset
|
| - self.buffer = deque()
|
| - self.bytes_buffered = 0
|
| - self.last_position = 0
|
| - self.last_data = None
|
| - self.StartDownloadThread(start_byte=offset,
|
| - progress_callback=self.progress_callback)
|
| - else:
|
| - raise IOError('Daisy-chain download wrapper does not support '
|
| - 'seek mode %s' % whence)
|
| -
|
| - def seekable(self): # pylint: disable=invalid-name
|
| - return True
|
|
|