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Inada Naoki 2020-12-18 16:13:35 +09:00
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README.md
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@ -64,9 +64,9 @@ See note below for detail.
## Install
$ pip install msgpack
```
$ pip install msgpack
```
### Pure Python implementation
@ -103,18 +103,18 @@ msgpack provides `dumps` and `loads` as an alias for compatibility with
`unpack` and `load` unpacks from a file-like object.
```pycon
>>> import msgpack
>>> msgpack.packb([1, 2, 3], use_bin_type=True)
'\x93\x01\x02\x03'
>>> msgpack.unpackb(_, raw=False)
[1, 2, 3]
>>> import msgpack
>>> msgpack.packb([1, 2, 3], use_bin_type=True)
'\x93\x01\x02\x03'
>>> msgpack.unpackb(_, raw=False)
[1, 2, 3]
```
`unpack` unpacks msgpack's array to Python's list, but can also unpack to tuple:
```pycon
>>> msgpack.unpackb(b'\x93\x01\x02\x03', use_list=False, raw=False)
(1, 2, 3)
>>> msgpack.unpackb(b'\x93\x01\x02\x03', use_list=False, raw=False)
(1, 2, 3)
```
You should always specify the `use_list` keyword argument for backward compatibility.
@ -129,18 +129,18 @@ Read the docstring for other options.
stream (or from bytes provided through its `feed` method).
```py
import msgpack
from io import BytesIO
import msgpack
from io import BytesIO
buf = BytesIO()
for i in range(100):
buf.write(msgpack.packb(i, use_bin_type=True))
buf = BytesIO()
for i in range(100):
buf.write(msgpack.packb(i, use_bin_type=True))
buf.seek(0)
buf.seek(0)
unpacker = msgpack.Unpacker(buf, raw=False)
for unpacked in unpacker:
print(unpacked)
unpacker = msgpack.Unpacker(buf, raw=False)
for unpacked in unpacker:
print(unpacked)
```
@ -150,27 +150,27 @@ It is also possible to pack/unpack custom data types. Here is an example for
`datetime.datetime`.
```py
import datetime
import msgpack
import datetime
import msgpack
useful_dict = {
"id": 1,
"created": datetime.datetime.now(),
}
useful_dict = {
"id": 1,
"created": datetime.datetime.now(),
}
def decode_datetime(obj):
if '__datetime__' in obj:
obj = datetime.datetime.strptime(obj["as_str"], "%Y%m%dT%H:%M:%S.%f")
return obj
def decode_datetime(obj):
if '__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
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, use_bin_type=True)
this_dict_again = msgpack.unpackb(packed_dict, object_hook=decode_datetime, raw=False)
packed_dict = msgpack.packb(useful_dict, default=encode_datetime, use_bin_type=True)
this_dict_again = msgpack.unpackb(packed_dict, object_hook=decode_datetime, raw=False)
```
`Unpacker`'s `object_hook` callback receives a dict; the
@ -183,25 +183,25 @@ key-value pairs.
It is also possible to pack/unpack custom data types using the **ext** type.
```pycon
>>> import msgpack
>>> import array
>>> def default(obj):
... if isinstance(obj, array.array) and obj.typecode == 'd':
... return msgpack.ExtType(42, obj.tostring())
... raise TypeError("Unknown type: %r" % (obj,))
...
>>> def ext_hook(code, data):
... if code == 42:
... a = array.array('d')
... a.fromstring(data)
... return a
... return ExtType(code, data)
...
>>> data = array.array('d', [1.2, 3.4])
>>> packed = msgpack.packb(data, default=default, use_bin_type=True)
>>> unpacked = msgpack.unpackb(packed, ext_hook=ext_hook, raw=False)
>>> data == unpacked
True
>>> import msgpack
>>> import array
>>> def default(obj):
... if isinstance(obj, array.array) and obj.typecode == 'd':
... return msgpack.ExtType(42, obj.tostring())
... raise TypeError("Unknown type: %r" % (obj,))
...
>>> def ext_hook(code, data):
... if code == 42:
... a = array.array('d')
... a.fromstring(data)
... return a
... return ExtType(code, data)
...
>>> data = array.array('d', [1.2, 3.4])
>>> packed = msgpack.packb(data, default=default, use_bin_type=True)
>>> unpacked = msgpack.unpackb(packed, ext_hook=ext_hook, raw=False)
>>> data == unpacked
True
```
@ -226,11 +226,11 @@ You can pack into and unpack from this old spec using `use_bin_type=False`
and `raw=True` options.
```pycon
>>> import msgpack
>>> msgpack.unpackb(msgpack.packb([b'spam', u'eggs'], use_bin_type=False), raw=True)
[b'spam', b'eggs']
>>> msgpack.unpackb(msgpack.packb([b'spam', u'eggs'], use_bin_type=True), raw=False)
[b'spam', 'eggs']
>>> import msgpack
>>> msgpack.unpackb(msgpack.packb([b'spam', u'eggs'], use_bin_type=False), raw=True)
[b'spam', b'eggs']
>>> msgpack.unpackb(msgpack.packb([b'spam', u'eggs'], use_bin_type=True), raw=False)
[b'spam', 'eggs']
```
### ext type
@ -238,10 +238,10 @@ and `raw=True` options.
To use the **ext** type, pass `msgpack.ExtType` object to packer.
```pycon
>>> import msgpack
>>> packed = msgpack.packb(msgpack.ExtType(42, b'xyzzy'))
>>> msgpack.unpackb(packed)
ExtType(code=42, data='xyzzy')
>>> import msgpack
>>> packed = msgpack.packb(msgpack.ExtType(42, b'xyzzy'))
>>> msgpack.unpackb(packed)
ExtType(code=42, data='xyzzy')
```
You can use it with `default` and `ext_hook`. See below.