def testSeekPartialBuffer(self): """Tests seeking back partially within the buffer.""" tmp_file = self._GetTestFile() read_size = TRANSFER_BUFFER_SIZE with open(tmp_file, 'rb') as stream: wrapper = ResumableStreamingJsonUploadWrapper( stream, TRANSFER_BUFFER_SIZE * 3, test_small_buffer=True) position = 0 for _ in xrange(3): data = wrapper.read(read_size) self.assertEqual( self._temp_test_file_contents[position:position + read_size], data, 'Data from position %s to %s did not match file contents.' % (position, position + read_size)) position += len(data) data = wrapper.read(read_size / 2) # Buffer contents should now be have contents from: # read_size/2 through 7*read_size/2. position = read_size / 2 wrapper.seek(position) data = wrapper.read() self.assertEqual( self._temp_test_file_contents[-len(data):], data, 'Data from position %s to EOF did not match file contents.' % position)
def testSeekPartialBuffer(self): """Tests seeking back partially within the buffer.""" tmp_file = self._GetTestFile() read_size = TRANSFER_BUFFER_SIZE with open(tmp_file, 'rb') as stream: wrapper = ResumableStreamingJsonUploadWrapper(stream, TRANSFER_BUFFER_SIZE * 3, test_small_buffer=True) position = 0 for _ in range(3): data = wrapper.read(read_size) self.assertEqual( self._temp_test_file_contents[position:position + read_size], data, 'Data from position %s to %s did not match file contents.' % (position, position + read_size)) position += len(data) data = wrapper.read(read_size // 2) # Buffer contents should now be have contents from: # read_size/2 through 7*read_size/2. position = read_size // 2 wrapper.seek(position) data = wrapper.read() self.assertEqual( self._temp_test_file_contents[-len(data):], data, 'Data from position %s to EOF did not match file contents.' % position)
def _testSeekBack(self, initial_reads, buffer_size, seek_back_amount): """Tests reading then seeking backwards. This function simulates an upload that is resumed after a connection break. It reads one transfer buffer at a time until it reaches initial_position, then seeks backwards (as if the server did not receive some of the bytes) and reads to the end of the file, ensuring the data read after the seek matches the original file. Args: initial_reads: List of integers containing read sizes to perform before seek. buffer_size: Maximum buffer size for the wrapper. seek_back_amount: Number of bytes to seek backward. Raises: AssertionError on wrong data returned by the wrapper. """ tmp_file = self._GetTestFile() initial_position = 0 for read_size in initial_reads: initial_position += read_size self.assertGreaterEqual( buffer_size, seek_back_amount, 'seek_back_amount must be less than initial position %s ' '(but was actually: %s)' % (buffer_size, seek_back_amount)) self.assertLess( initial_position, self._temp_test_file_len, 'initial_position must be less than test file size %s ' '(but was actually: %s)' % (self._temp_test_file_len, initial_position)) with open(tmp_file, 'rb') as stream: wrapper = ResumableStreamingJsonUploadWrapper( stream, buffer_size, test_small_buffer=True) position = 0 for read_size in initial_reads: data = wrapper.read(read_size) self.assertEqual( self._temp_test_file_contents[position:position + read_size], data, 'Data from position %s to %s did not match file contents.' % (position, position + read_size)) position += len(data) wrapper.seek(initial_position - seek_back_amount) self.assertEqual(wrapper.tell(), initial_position - seek_back_amount) data = wrapper.read() self.assertEqual( self._temp_test_file_len - (initial_position - seek_back_amount), len(data), 'Unexpected data length with initial pos %s seek_back_amount %s. ' 'Expected: %s, actual: %s.' % (initial_position, seek_back_amount, self._temp_test_file_len - (initial_position - seek_back_amount), len(data))) self.assertEqual( self._temp_test_file_contents[-len(data):], data, 'Data from position %s to EOF did not match file contents.' % position)
def testSeekEnd(self): tmp_file = self._GetTestFile() for buffer_size in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1): for seek_back in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1): expect_exception = seek_back > buffer_size with open(tmp_file, 'rb') as stream: wrapper = ResumableStreamingJsonUploadWrapper(stream, buffer_size, test_small_buffer=True) # Read to the end. while wrapper.read(TRANSFER_BUFFER_SIZE): pass try: wrapper.seek(seek_back, whence=os.SEEK_END) if expect_exception: self.fail('Did not get expected CommandException for ' 'seek_back size %s, buffer size %s' % (seek_back, buffer_size)) except CommandException as e: if not expect_exception: self.fail('Got unexpected CommandException "%s" for ' 'seek_back size %s, buffer size %s' % (str(e), seek_back, buffer_size))
def testSeekEnd(self): tmp_file = self._GetTestFile() for buffer_size in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1): for seek_back in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1): expect_exception = seek_back > buffer_size with open(tmp_file, 'rb') as stream: wrapper = ResumableStreamingJsonUploadWrapper( stream, buffer_size, test_small_buffer=True) # Read to the end. while wrapper.read(TRANSFER_BUFFER_SIZE): pass try: wrapper.seek(seek_back, whence=os.SEEK_END) if expect_exception: self.fail( 'Did not get expected CommandException for ' 'seek_back size %s, buffer size %s' % (seek_back, buffer_size)) except CommandException, e: if not expect_exception: self.fail( 'Got unexpected CommandException "%s" for ' 'seek_back size %s, buffer size %s' % (str(e), seek_back, buffer_size))
def testReadInChunksWithSeekToBeginning(self): """Reads one buffer, then seeks to 0 and reads chunks until the end.""" tmp_file = self._GetTestFile() for initial_read in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1, TRANSFER_BUFFER_SIZE * 2 - 1, TRANSFER_BUFFER_SIZE * 2, TRANSFER_BUFFER_SIZE * 2 + 1, TRANSFER_BUFFER_SIZE * 3 - 1, TRANSFER_BUFFER_SIZE * 3, TRANSFER_BUFFER_SIZE * 3 + 1): for buffer_size in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1, self._temp_test_file_len - 1, self._temp_test_file_len, self._temp_test_file_len + 1): # Can't seek to 0 if the buffer is too small, so we expect an # exception. expect_exception = buffer_size < self._temp_test_file_len with open(tmp_file, 'rb') as stream: wrapper = ResumableStreamingJsonUploadWrapper( stream, buffer_size, test_small_buffer=True) wrapper.read(initial_read) # CalculateMd5FromContents seeks to 0, reads in chunks, then seeks # to 0 again. try: hex_digest = CalculateMd5FromContents(wrapper) if expect_exception: self.fail('Did not get expected CommandException for ' 'initial read size %s, buffer size %s' % (initial_read, buffer_size)) except CommandException, e: if not expect_exception: self.fail('Got unexpected CommandException "%s" for ' 'initial read size %s, buffer size %s' % (str(e), initial_read, buffer_size)) if not expect_exception: with open(tmp_file, 'rb') as stream: actual = CalculateMd5FromContents(stream) self.assertEqual( actual, hex_digest, 'Digests not equal for initial read size %s, buffer size %s' % (initial_read, buffer_size))
def testReadInChunksWithSeekToBeginning(self): """Reads one buffer, then seeks to 0 and reads chunks until the end.""" tmp_file = self._GetTestFile() for initial_read in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1, TRANSFER_BUFFER_SIZE * 2 - 1, TRANSFER_BUFFER_SIZE * 2, TRANSFER_BUFFER_SIZE * 2 + 1, TRANSFER_BUFFER_SIZE * 3 - 1, TRANSFER_BUFFER_SIZE * 3, TRANSFER_BUFFER_SIZE * 3 + 1): for buffer_size in (TRANSFER_BUFFER_SIZE - 1, TRANSFER_BUFFER_SIZE, TRANSFER_BUFFER_SIZE + 1, self._temp_test_file_len - 1, self._temp_test_file_len, self._temp_test_file_len + 1): # Can't seek to 0 if the buffer is too small, so we expect an # exception. expect_exception = buffer_size < self._temp_test_file_len with open(tmp_file, 'rb') as stream: wrapper = ResumableStreamingJsonUploadWrapper( stream, buffer_size, test_small_buffer=True) wrapper.read(initial_read) # CalculateMd5FromContents seeks to 0, reads in chunks, then seeks # to 0 again. try: hex_digest = CalculateMd5FromContents(wrapper) if expect_exception: self.fail( 'Did not get expected CommandException for ' 'initial read size %s, buffer size %s' % (initial_read, buffer_size)) except CommandException, e: if not expect_exception: self.fail( 'Got unexpected CommandException "%s" for ' 'initial read size %s, buffer size %s' % (str(e), initial_read, buffer_size)) if not expect_exception: with open(tmp_file, 'rb') as stream: actual = CalculateMd5FromContents(stream) self.assertEqual( actual, hex_digest, 'Digests not equal for initial read size %s, buffer size %s' % (initial_read, buffer_size))