Python snappy.uncompress() Examples

def decompress(data, compressor_id):
    if compressor_id == SnappyContext.compressor_id:
        # python-snappy doesn't support the buffer interface.
        # https://github.com/andrix/python-snappy/issues/65
        # This only matters when data is a memoryview since
        # id(bytes(data)) == id(data) when data is a bytes.
        # NOTE: bytes(memoryview) returns the memoryview repr
        # in Python 2.7. The right thing to do in 2.7 is call
        # memoryview.tobytes(), but we currently only use
        # memoryview in Python 3.x.
        return snappy.uncompress(bytes(data))
    elif compressor_id == ZlibContext.compressor_id:
        return zlib.decompress(data)
    elif compressor_id == ZstdContext.compressor_id:
        # ZstdDecompressor is not thread safe.
        # TODO: Use a pool?
        return ZstdDecompressor().decompress(data)
    else:
        raise ValueError("Unknown compressorId %d" % (compressor_id,)) 

def post(self):
        buf = snappy.uncompress(pecan.request.body)
        f = remote_pb2.WriteRequest()
        f.ParseFromString(buf)
        measures_by_rid = collections.defaultdict(dict)
        for ts in f.timeseries:
            attrs = dict((l.name, l.value) for l in ts.labels)
            original_rid = (attrs.get("job", "none"),
                            attrs.get("instance", "none"))
            name = attrs['__name__']
            if ts.samples:
                data = [{'timestamp': s.timestamp_ms / 1000.0,
                         'value': s.value} for s in ts.samples]
                measures_by_rid[original_rid][name] = validate(
                    MeasuresListSchema, data)

        creator = pecan.request.auth_helper.get_current_user(pecan.request)

        measures_to_batch = {}
        for (job, instance), measures in measures_by_rid.items():
            original_rid = '%s@%s' % (job, instance)
            rid = ResourceUUID(original_rid, creator=creator)
            metric_names = list(measures.keys())
            timeout = pecan.request.conf.api.operation_timeout
            metrics = get_or_create_resource_and_metrics.retry_with(
                stop=tenacity.stop_after_delay(timeout))(
                    creator, rid, original_rid, metric_names,
                    dict(job=job, instance=instance),
                    "prometheus", self.PROMETHEUS_RESOURCE_TYPE)

            for metric in metrics:
                enforce("post measures", metric)

            measures_to_batch.update(
                dict((metric.id, measures[metric.name]) for metric in
                     metrics if metric.name in measures))

        pecan.request.incoming.add_measures_batch(measures_to_batch)
        pecan.response.status = 202 

def decompress(data, compressor_id):
    if compressor_id == SnappyContext.compressor_id:
        # python-snappy doesn't support the buffer interface.
        # https://github.com/andrix/python-snappy/issues/65
        # This only matters when data is a memoryview since
        # id(bytes(data)) == id(data) when data is a bytes.
        # NOTE: bytes(memoryview) returns the memoryview repr
        # in Python 2.7. The right thing to do in 2.7 is call
        # memoryview.tobytes(), but we currently only use
        # memoryview in Python 3.x.
        return snappy.uncompress(bytes(data))
    elif compressor_id == ZlibContext.compressor_id:
        return zlib.decompress(data)
    else:
        raise ValueError("Unknown compressorId %d" % (compressor_id,)) 

def _unpack_msgpack_snappy(str):
    if str.startswith(b'S'):
        tmp = snappy.uncompress(str[1:])
        # print "SNAPPY: ", len(str), len(tmp)
        obj = msgpack.loads(tmp, encoding='utf-8')
    elif str.startswith(b'\0'):
        obj = msgpack.loads(str[1:], encoding='utf-8')
    else:
        return None
    
    return obj 

def decompress(data):
    """
    Decompresses the given data via the snappy algorithm.

    If ``python-snappy`` is not installed a ``RuntimeError`` is raised.
    """
    if not snappy_available:
        raise RuntimeError("Snappy compression unavailable.")

    buff_offset = len(raw_header)  # skip the header
    length = len(data) - len(raw_header)

    output = BytesIO()

    while buff_offset <= length:
        block_size = struct.unpack_from("!i", data, buff_offset)[0]
        buff_offset += struct.calcsize("!i")

        block = struct.unpack_from("!%ds" % block_size, data, buff_offset)[0]
        buff_offset += block_size

        output.write(snappy.uncompress(block))

    result = output.getvalue()

    output.close()

    return result 

def _unpack_msgpack_snappy(str):
    if str.startswith(b'S'):
        tmp = snappy.uncompress(str[1:])
        # print "SNAPPY: ", len(str), len(tmp)
        obj = msgpack.loads(tmp, encoding='utf-8')
    elif str.startswith(b'\0'):
        obj = msgpack.loads(str[1:], encoding='utf-8')
    else:
        return None
    
    return obj 

def _unpack_msgpack_snappy(str):
    if str.startswith(b'S'):
        tmp = snappy.uncompress(str[1:])
        # print "SNAPPY: ", len(str), len(tmp)
        obj = msgpack.loads(tmp, encoding='utf-8')
    elif str.startswith(b'\0'):
        obj = msgpack.loads(str[1:], encoding='utf-8')
    else:
        return None
    
    return obj