# -*- coding: utf-8 -*-
# Copyright 2014 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# 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.
"""Helper functions for progress callbacks."""
import logging
import sys
from gslib.util import MakeHumanReadable
from gslib.util import UTF8
# Default upper and lower bounds for progress callback frequency.
_START_BYTES_PER_CALLBACK = 1024*64
_MAX_BYTES_PER_CALLBACK = 1024*1024*100
# Max width of URL to display in progress indicator. Wide enough to allow
# 15 chars for x/y display on an 80 char wide terminal.
MAX_PROGRESS_INDICATOR_COLUMNS = 65
class ProgressCallbackWithBackoff(object):
"""Makes progress callbacks with exponential backoff to a maximum value.
This prevents excessive log message output.
"""
def __init__(self, total_size, callback_func,
start_bytes_per_callback=_START_BYTES_PER_CALLBACK,
max_bytes_per_callback=_MAX_BYTES_PER_CALLBACK,
calls_per_exponent=10):
"""Initializes the callback with backoff.
Args:
total_size: Total bytes to process. If this is None, size is not known
at the outset.
callback_func: Func of (int: processed_so_far, int: total_bytes)
used to make callbacks.
start_bytes_per_callback: Lower bound of bytes per callback.
max_bytes_per_callback: Upper bound of bytes per callback.
calls_per_exponent: Number of calls to make before reducing rate.
"""
self._bytes_per_callback = start_bytes_per_callback
self._callback_func = callback_func
self._calls_per_exponent = calls_per_exponent
self._max_bytes_per_callback = max_bytes_per_callback
self._total_size = total_size
self._bytes_processed_since_callback = 0
self._callbacks_made = 0
self._total_bytes_processed = 0
def Progress(self, bytes_processed):
"""Tracks byte processing progress, making a callback if necessary."""
self._bytes_processed_since_callback += bytes_processed
if (self._bytes_processed_since_callback > self._bytes_per_callback or
(self._total_bytes_processed + self._bytes_processed_since_callback >=
self._total_size and self._total_size is not None)):
self._total_bytes_processed += self._bytes_processed_since_callback
# TODO: We check if >= total_size and truncate because JSON uploads count
# headers+metadata during their send progress. If the size is unknown,
# we can't do this and the progress message will make it appear that we
# send more than the original stream.
if self._total_size is not None:
bytes_sent = min(self._total_bytes_processed, self._total_size)
else:
bytes_sent = self._total_bytes_processed
self._callback_func(bytes_sent, self._total_size)
self._bytes_processed_since_callback = 0
self._callbacks_made += 1
if self._callbacks_made > self._calls_per_exponent:
self._bytes_per_callback = min(self._bytes_per_callback * 2,
self._max_bytes_per_callback)
self._callbacks_made = 0
def ConstructAnnounceText(operation_name, url_string):
"""Constructs announce text for ongoing operations on url_to_display.
This truncates the text to a maximum of MAX_PROGRESS_INDICATOR_COLUMNS.
Thus, concurrent output (gsutil -m) leaves progress counters in a readable
(fixed) position.
Args:
operation_name: String describing the operation, i.e.
'Uploading' or 'Hashing'.
url_string: String describing the file/object being processed.
Returns:
Formatted announce text for outputting operation progress.
"""
# Operation name occupies 11 characters (enough for 'Downloading'), plus a
# space. The rest is used for url_to_display. If a longer operation name is
# used, it will be truncated. We can revisit this size if we need to support
# a longer operation, but want to make sure the terminal output is meaningful.
justified_op_string = operation_name[:11].ljust(12)
start_len = len(justified_op_string)
end_len = len(': ')
if (start_len + len(url_string) + end_len >
MAX_PROGRESS_INDICATOR_COLUMNS):
ellipsis_len = len('...')
url_string = '...%s' % url_string[
-(MAX_PROGRESS_INDICATOR_COLUMNS - start_len - end_len - ellipsis_len):]
base_announce_text = '%s%s:' % (justified_op_string, url_string)
format_str = '{0:%ds}' % MAX_PROGRESS_INDICATOR_COLUMNS
return format_str.format(base_announce_text.encode(UTF8))
class FileProgressCallbackHandler(object):
"""Outputs progress info for large operations like file copy or hash."""
def __init__(self, announce_text, logger, start_byte=0,
override_total_size=None):
"""Initializes the callback handler.
Args:
announce_text: String describing the operation.
logger: For outputting log messages.
start_byte: The beginning of the file component, if one is being used.
override_total_size: The size of the file component, if one is being used.
"""
self._announce_text = announce_text
self._logger = logger
self._start_byte = start_byte
self._override_total_size = override_total_size
# Ensures final newline is written once even if we get multiple callbacks.
self._last_byte_written = False
# Function signature is in boto callback format, which cannot be changed.
def call(self, # pylint: disable=invalid-name
last_byte_processed,
total_size):
"""Prints an overwriting line to stderr describing the operation progress.
Args:
last_byte_processed: The last byte processed in the file. For file
components, this number should be in the range
[start_byte:start_byte + override_total_size].
total_size: Total size of the ongoing operation.
"""
if not self._logger.isEnabledFor(logging.INFO) or self._last_byte_written:
return
if self._override_total_size:
total_size = self._override_total_size
if total_size:
total_size_string = '/%s' % MakeHumanReadable(total_size)
else:
total_size_string = ''
# Use sys.stderr.write instead of self.logger.info so progress messages
# output on a single continuously overwriting line.
# TODO: Make this work with logging.Logger.
sys.stderr.write('%s%s%s \r' % (
self._announce_text,
MakeHumanReadable(last_byte_processed - self._start_byte),
total_size_string))
if total_size and last_byte_processed - self._start_byte == total_size:
self._last_byte_written = True
sys.stderr.write('\n')