u-msgpack-python

A portable, lightweight MessagePack serializer and deserializer written in pure Python.


Keywords
msgpack, serialization, deserialization
License
MIT
Install
pip install u-msgpack-python==2.8.0

Documentation

u-msgpack-python Tests Status Docs Status GitHub release License

u-msgpack-python is a lightweight MessagePack serializer and deserializer module written in pure Python, compatible with Python 2 and 3, as well CPython and PyPy implementations of Python. u-msgpack-python is fully compliant with the latest MessagePack specification. In particular, it supports the new binary, UTF-8 string, application-defined ext, and timestamp types.

u-msgpack-python is currently distributed as a package on PyPI and as a single file module.

Installation

With pip:

$ pip install u-msgpack-python

With easy_install:

$ easy_install u-msgpack-python

or simply drop umsgpack.py into your project!

$ wget https://raw.github.com/vsergeev/u-msgpack-python/master/umsgpack/__init__.py -O umsgpack.py

Examples

Basic Example:

>>> import umsgpack
>>> umsgpack.packb({u"compact": True, u"schema": 0})
b'\x82\xa7compact\xc3\xa6schema\x00'
>>> umsgpack.unpackb(_)
{u'compact': True, u'schema': 0}
>>> 

A more complicated example:

>>> umsgpack.packb([1, True, False, 0xffffffff, {u"foo": b"\x80\x01\x02", \
...                 u"bar": [1,2,3, {u"a": [1,2,3,{}]}]}, -1, 2.12345])
b'\x97\x01\xc3\xc2\xce\xff\xff\xff\xff\x82\xa3foo\xc4\x03\x80\x01\
\x02\xa3bar\x94\x01\x02\x03\x81\xa1a\x94\x01\x02\x03\x80\xff\xcb\
@\x00\xfc\xd3Z\x85\x87\x94'
>>> umsgpack.unpackb(_)
[1, True, False, 4294967295, {u'foo': b'\x80\x01\x02', \
 u'bar': [1, 2, 3, {u'a': [1, 2, 3, {}]}]}, -1, 2.12345]
>>> 

Streaming serialization with file-like objects:

>>> f = open('test.bin', 'wb')
>>> umsgpack.pack({u"compact": True, u"schema": 0}, f)
>>> umsgpack.pack([1,2,3], f)
>>> f.close()
>>> 
>>> f = open('test.bin', 'rb')
>>> umsgpack.unpack(f)
{u'compact': True, u'schema': 0}
>>> umsgpack.unpack(f)
[1, 2, 3]
>>> f.close()
>>> 

Serializing and deserializing a raw Ext type:

>>> # Create an Ext object with type 5 and data b"\x01\x02\x03"
... foo = umsgpack.Ext(5, b"\x01\x02\x03")
>>> umsgpack.packb({u"stuff": foo, u"awesome": True})
b'\x82\xa5stuff\xc7\x03\x05\x01\x02\x03\xa7awesome\xc3'
>>> 
>>> bar = umsgpack.unpackb(_)
>>> print(bar['stuff'])
Ext Object (Type: 5, Data: 0x01 0x02 0x03)
>>> bar['stuff'].type
5
>>> bar['stuff'].data
b'\x01\x02\x03'
>>> 

Serializing and deserializing application-defined types with ext_serializable():

>>> @umsgpack.ext_serializable(0x50)
... class Point(collections.namedtuple('Point', ['x', 'y'])):
...     def packb(self):
...         return struct.pack(">ii", self.x, self.y)
...     @staticmethod
...     def unpackb(data):
...         return Point(*struct.unpack(">ii", data))
... 
>>> umsgpack.packb(Point(1, 2))
b'\xd7P\x00\x00\x00\x01\x00\x00\x00\x02'
>>> umsgpack.unpackb(_)
Point(x=1, y=2)
>>> 

Serializing and deserializing application-defined types with Ext handlers:

>>> umsgpack.packb([complex(1,2), decimal.Decimal("0.31")],
...  ext_handlers = {
...   complex: lambda obj: umsgpack.Ext(0x30, struct.pack("ff", obj.real, obj.imag)),
...   decimal.Decimal: lambda obj: umsgpack.Ext(0x40, str(obj).encode()),
... })
b'\x92\xd70\x00\x00\x80?\x00\x00\x00@\xd6@0.31'
>>> umsgpack.unpackb(_,
...  ext_handlers = {
...   0x30: lambda ext: complex(*struct.unpack("ff", ext.data)),
...   0x40: lambda ext: decimal.Decimal(ext.data.decode()),
... })
[(1+2j), Decimal('0.31')]
>>> 

Python standard library style names dump, dumps, load, loads are also available:

>>> umsgpack.dumps({u"compact": True, u"schema": 0})
b'\x82\xa7compact\xc3\xa6schema\x00'
>>> umsgpack.loads(_)
{u'compact': True, u'schema': 0}
>>> 
>>> f = open('test.bin', 'wb')
>>> umsgpack.dump({u"compact": True, u"schema": 0}, f)
>>> f.close()
>>> 
>>> f = open('test.bin', 'rb')
>>> umsgpack.load(f)
{u'compact': True, u'schema': 0}
>>> 

Documentation

Documentation is hosted at https://u-msgpack-python.readthedocs.io.

To build documentation locally with Sphinx, run:

cd docs
make html

Sphinx will produce the HTML documentation in docs/_build/html/.

Run make help to see other output targets (LaTeX, man, text, etc.).

Testing

The included unit tests may be run with test_umsgpack.py, under your favorite interpreter.

$ python2 test_umsgpack.py
$ python3 test_umsgpack.py
$ pypy test_umsgpack.py
$ pypy3 test_umsgpack.py

Alternatively, you can use tox or detox to test multiple Python versions at once.

$ pip install tox
$ tox

License

u-msgpack-python is MIT licensed. See the included LICENSE file for more details.