def fetch_data(blob_key,
start_index,
end_index,
_make_sync_call=apiproxy_stub_map.MakeSyncCall):
"""Fetch data for blob.
See docstring for ext.blobstore.fetch_data for more details.
Args:
blob: BlobKey, str or unicode representation of BlobKey of
blob to fetch data from.
start_index: Start index of blob data to fetch. May not be negative.
end_index: End index (exclusive) of blob data to fetch. Must be
>= start_index.
Returns:
str containing partial data of blob. See docstring for
ext.blobstore.fetch_data for more details.
Raises:
See docstring for ext.blobstore.fetch_data for more details.
"""
if not isinstance(start_index, (int, long)):
raise TypeError('start_index must be integer.')
if not isinstance(end_index, (int, long)):
raise TypeError('end_index must be integer.')
if isinstance(blob_key, BlobKey):
blob_key = str(blob_key).decode('utf-8')
elif isinstance(blob_key, str):
blob_key = blob_key.decode('utf-8')
elif not isinstance(blob_key, unicode):
raise TypeError('Blob-key must be str, unicode or BlobKey: %s' %
blob_key)
if start_index < 0:
raise DataIndexOutOfRangeError('May not fetch blob at negative index.')
if end_index < start_index:
raise DataIndexOutOfRangeError('Start index %d > end index %d' %
(start_index, end_index))
fetch_size = end_index - start_index + 1
if fetch_size > MAX_BLOB_FETCH_SIZE:
raise BlobFetchSizeTooLargeError('Blob fetch size is too large: %d' %
fetch_size)
request = blobstore_service_pb.FetchDataRequest()
response = blobstore_service_pb.FetchDataResponse()
request.set_blob_key(blob_key)
request.set_start_index(start_index)
request.set_end_index(end_index)
try:
_make_sync_call('blobstore', 'FetchData', request, response)
except apiproxy_errors.ApplicationError, e:
raise _ToBlobstoreError(e)
def fetch_data_async(blob_key, start_index, end_index, rpc=None):
"""Fetch data for blob -- async version.
See docstring for ext.blobstore.fetch_data for more details.
Args:
blob: BlobKey, str or unicode representation of BlobKey of
blob to fetch data from.
start_index: Start index of blob data to fetch. May not be negative.
end_index: End index (exclusive) of blob data to fetch. Must be
>= start_index.
rpc: Optional UserRPC object.
Returns:
A UserRPC whose result will be a str as returned by fetch_data().
Raises:
See docstring for ext.blobstore.fetch_data for more details.
"""
if not isinstance(start_index, six.integer_types):
raise TypeError('start_index must be integer.')
if not isinstance(end_index, six.integer_types):
raise TypeError('end_index must be integer.')
if isinstance(blob_key, BlobKey):
blob_key = str(blob_key).decode('utf-8')
elif isinstance(blob_key, str):
blob_key = blob_key.decode('utf-8')
elif not isinstance(blob_key, six.text_type):
raise TypeError('Blob-key must be str, unicode or BlobKey: %s' % blob_key)
if start_index < 0:
raise DataIndexOutOfRangeError(
'May not fetch blob at negative index.')
if end_index < start_index:
raise DataIndexOutOfRangeError(
'Start index %d > end index %d' % (start_index, end_index))
fetch_size = end_index - start_index + 1
if fetch_size > MAX_BLOB_FETCH_SIZE:
raise BlobFetchSizeTooLargeError(
'Blob fetch size is too large: %d' % fetch_size)
request = blobstore_service_pb.FetchDataRequest()
response = blobstore_service_pb.FetchDataResponse()
request.set_blob_key(blob_key)
request.set_start_index(start_index)
request.set_end_index(end_index)
return _make_async_call(rpc, 'FetchData', request, response,
_get_result_hook, lambda rpc: rpc.response.data())
def fetch_data_async(blob_key, start_index, end_index, rpc=None):
"""Asynchronously fetches the data for a blob.
Args:
blob_key: A `BlobKey`, string, or Unicode representation of a `BlobKey` of
the blob from which you want to fetch data.
start_index: The start index value of the blob data to fetch. This argument
cannot be set to a negative value.
end_index: The end index value (exclusive) of the blob data to fetch. This
argument must be greater than or equal to the `start_index` value.
rpc: Optional UserRPC object.
Returns:
A UserRPC whose result will be a string as returned by `fetch_data()`.
"""
if not isinstance(start_index, (int, long)):
raise TypeError('start_index must be an integer.')
if not isinstance(end_index, (int, long)):
raise TypeError('end_index must be an integer.')
if isinstance(blob_key, BlobKey):
blob_key = str(blob_key).decode('utf-8')
elif isinstance(blob_key, str):
blob_key = blob_key.decode('utf-8')
elif not isinstance(blob_key, unicode):
raise TypeError('blob_key must be str, Unicode or BlobKey: %s' % blob_key)
if start_index < 0:
raise DataIndexOutOfRangeError(
'Cannot fetch blob at negative index.')
if end_index < start_index:
raise DataIndexOutOfRangeError(
'Start index %d > end index %d' % (start_index, end_index))
fetch_size = end_index - start_index + 1
if fetch_size > MAX_BLOB_FETCH_SIZE:
raise BlobFetchSizeTooLargeError(
'Blob fetch size is too large: %d' % fetch_size)
request = blobstore_service_pb.FetchDataRequest()
response = blobstore_service_pb.FetchDataResponse()
request.set_blob_key(blob_key)
request.set_start_index(start_index)
request.set_end_index(end_index)
return _make_async_call(rpc, 'FetchData', request, response,
_get_result_hook, lambda rpc: rpc.response.data())
