- author
INADA Naoki
- version
0.2.0
- date
2012-06-27
Use packb
for packing and unpackb
for unpacking. msgpack provides dumps
and loads
as alias for compatibility with json
and pickle
.
pack
and dump
packs to file-like object. unpack
and load
unpacks from file-like object.
>>> import msgpack >>> msgpack.packb([1, 2, 3]) 'x93x01x02x03' >>> msgpack.unpackb(_) (1, 2, 3)
unpack
unpacks msgpack's array to Python's tuple. To unpack it to list, Use use_list
option.
>>> msgpack.unpackb(b'x93x01x02x03', use_list=True) [1, 2, 3]
Read docstring for other options.
Unpacker
is "streaming unpacker". It unpacks multiple objects from one stream.
import msgpack
from io import BytesIO
buf = BytesIO()
for i in range(100):
buf.write(msgpack.packb(range(i)))
buf.seek(0)
unpacker = msgpack.Unpacker()
while True:
data = buf.read(16)
if not data:
break
unpacker.feed(data)
for unpacked in unpacker:
print unpacked
Also possible to pack/unpack user's data types. Here is an example for datetime.datetime
.
import datetime
import msgpack
useful_dict = {
"id": 1,
"created": datetime.datetime.now(),
}
def decode_datetime(obj):
if b'__datetime__' in obj:
obj = datetime.datetime.strptime(obj["as_str"], "%Y%m%dT%H:%M:%S.%f")
return obj
def encode_datetime(obj):
if isinstance(obj, datetime.datetime):
return {'__datetime__': True, 'as_str': obj.strftime("%Y%m%dT%H:%M:%S.%f")}
return obj
packed_dict = msgpack.packb(useful_dict, default=encode_datetime)
this_dict_again = msgpack.unpackb(packed_dict, object_hook=decode_datetime)
You can use pip
or easy_install
to install msgpack:
$ easy_install msgpack-python
or
$ pip install msgpack-python
msgpack provides some binary distribution for Windows. You can install msgpack without compiler with them.
When you can't use binary distribution, you need to install Visual Studio or Windows SDK on Windows. (NOTE: Visual C++ Express 2010 doesn't support amd64. Windows SDK is recommanded way to build amd64 msgpack without any fee.)
MessagePack uses nosetest for testing. Run test with following command:
$ nosetests test