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README: ` ->
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Inada Naoki
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README.md
74
README.md
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@ -28,10 +28,10 @@ msgpack is removed, and `import msgpack` fail.
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### Compatibility with the old format
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You can use ``use_bin_type=False`` option to pack ``bytes``
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You can use `use_bin_type=False` option to pack `bytes`
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object into raw type in the old msgpack spec, instead of bin type in new msgpack spec.
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You can unpack old msgpack format using ``raw=True`` option.
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You can unpack old msgpack format using `raw=True` option.
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It unpacks str (raw) type in msgpack into Python bytes.
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See note below for detail.
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@ -42,23 +42,23 @@ See note below for detail.
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* Python 2
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* The extension module does not support Python 2 anymore.
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The pure Python implementation (``msgpack.fallback``) is used for Python 2.
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The pure Python implementation (`msgpack.fallback`) is used for Python 2.
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* Packer
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* ``use_bin_type=True`` by default. bytes are encoded in bin type in msgpack.
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* `use_bin_type=True` by default. bytes are encoded in bin type in msgpack.
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**If you are still sing Python 2, you must use unicode for all string types.**
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You can use ``use_bin_type=False`` to encode into old msgpack format.
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* ``encoding`` option is removed. UTF-8 is used always.
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You can use `use_bin_type=False` to encode into old msgpack format.
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* `encoding` option is removed. UTF-8 is used always.
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* Unpacker
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* ``raw=False`` by default. It assumes str types are valid UTF-8 string
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* `raw=False` by default. It assumes str types are valid UTF-8 string
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and decode them to Python str (unicode) object.
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* ``encoding`` option is removed. You can use ``raw=True`` to support old format.
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* Default value of ``max_buffer_size`` is changed from 0 to 100 MiB.
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* Default value of ``strict_map_key`` is changed to True to avoid hashdos.
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You need to pass ``strict_map_key=False`` if you have data which contain map keys
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* `encoding` option is removed. You can use `raw=True` to support old format.
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* Default value of `max_buffer_size` is changed from 0 to 100 MiB.
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* Default value of `strict_map_key` is changed to True to avoid hashdos.
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You need to pass `strict_map_key=False` if you have data which contain map keys
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which type is not bytes or str.
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@ -70,10 +70,10 @@ See note below for detail.
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### Pure Python implementation
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The extension module in msgpack (``msgpack._cmsgpack``) does not support
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The extension module in msgpack (`msgpack._cmsgpack`) does not support
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Python 2 and PyPy.
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But msgpack provides a pure Python implementation (``msgpack.fallback``)
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But msgpack provides a pure Python implementation (`msgpack.fallback`)
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for PyPy and Python 2.
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Since the [pip](https://pip.pypa.io/) uses the pure Python implementation,
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@ -89,18 +89,18 @@ Without extension, using pure Python implementation on CPython runs slowly.
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## How to use
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NOTE: In examples below, I use ``raw=False`` and ``use_bin_type=True`` for users
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NOTE: In examples below, I use `raw=False` and `use_bin_type=True` for users
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using msgpack < 1.0. These options are default from msgpack 1.0 so you can omit them.
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### One-shot pack & unpack
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Use ``packb`` for packing and ``unpackb`` for unpacking.
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msgpack provides ``dumps`` and ``loads`` as an alias for compatibility with
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``json`` and ``pickle``.
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Use `packb` for packing and `unpackb` for unpacking.
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msgpack provides `dumps` and `loads` as an alias for compatibility with
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`json` and `pickle`.
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``pack`` and ``dump`` packs to a file-like object.
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``unpack`` and ``load`` unpacks from a file-like object.
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`pack` and `dump` packs to a file-like object.
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`unpack` and `load` unpacks from a file-like object.
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```pycon
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>>> import msgpack
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@ -110,14 +110,14 @@ msgpack provides ``dumps`` and ``loads`` as an alias for compatibility with
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[1, 2, 3]
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```
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``unpack`` unpacks msgpack's array to Python's list, but can also unpack to tuple:
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`unpack` unpacks msgpack's array to Python's list, but can also unpack to tuple:
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```pycon
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>>> msgpack.unpackb(b'\x93\x01\x02\x03', use_list=False, raw=False)
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(1, 2, 3)
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```
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You should always specify the ``use_list`` keyword argument for backward compatibility.
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You should always specify the `use_list` keyword argument for backward compatibility.
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See performance issues relating to `use_list option`_ below.
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Read the docstring for other options.
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@ -125,8 +125,8 @@ Read the docstring for other options.
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### Streaming unpacking
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``Unpacker`` is a "streaming unpacker". It unpacks multiple objects from one
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stream (or from bytes provided through its ``feed`` method).
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`Unpacker` is a "streaming unpacker". It unpacks multiple objects from one
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stream (or from bytes provided through its `feed` method).
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```py
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import msgpack
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@ -147,7 +147,7 @@ stream (or from bytes provided through its ``feed`` method).
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### Packing/unpacking of custom data type
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It is also possible to pack/unpack custom data types. Here is an example for
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``datetime.datetime``.
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`datetime.datetime`.
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```py
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import datetime
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@ -173,8 +173,8 @@ It is also possible to pack/unpack custom data types. Here is an example for
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this_dict_again = msgpack.unpackb(packed_dict, object_hook=decode_datetime, raw=False)
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```
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``Unpacker``'s ``object_hook`` callback receives a dict; the
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``object_pairs_hook`` callback may instead be used to receive a list of
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`Unpacker`'s `object_hook` callback receives a dict; the
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`object_pairs_hook` callback may instead be used to receive a list of
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key-value pairs.
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@ -207,8 +207,8 @@ It is also possible to pack/unpack custom data types using the **ext** type.
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### Advanced unpacking control
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As an alternative to iteration, ``Unpacker`` objects provide ``unpack``,
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``skip``, ``read_array_header`` and ``read_map_header`` methods. The former two
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As an alternative to iteration, `Unpacker` objects provide `unpack`,
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`skip`, `read_array_header` and `read_map_header` methods. The former two
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read an entire message from the stream, respectively de-serialising and returning
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the result, or ignoring it. The latter two methods return the number of elements
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in the upcoming container, so that each element in an array, or key-value pair
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@ -222,8 +222,8 @@ in a map, can be unpacked or skipped individually.
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Early versions of msgpack didn't distinguish string and binary types.
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The type for representing both string and binary types was named **raw**.
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You can pack into and unpack from this old spec using ``use_bin_type=False``
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and ``raw=True`` options.
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You can pack into and unpack from this old spec using `use_bin_type=False`
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and `raw=True` options.
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```pycon
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>>> import msgpack
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@ -235,7 +235,7 @@ and ``raw=True`` options.
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### ext type
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To use the **ext** type, pass ``msgpack.ExtType`` object to packer.
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To use the **ext** type, pass `msgpack.ExtType` object to packer.
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```pycon
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>>> import msgpack
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@ -244,7 +244,7 @@ To use the **ext** type, pass ``msgpack.ExtType`` object to packer.
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ExtType(code=42, data='xyzzy')
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```
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You can use it with ``default`` and ``ext_hook``. See below.
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You can use it with `default` and `ext_hook`. See below.
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### Security
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@ -252,24 +252,24 @@ You can use it with ``default`` and ``ext_hook``. See below.
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To unpacking data received from unreliable source, msgpack provides
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two security options.
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``max_buffer_size`` (default: 100*1024*1024) limits the internal buffer size.
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`max_buffer_size` (default: `100*1024*1024`) limits the internal buffer size.
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It is used to limit the preallocated list size too.
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``strict_map_key`` (default: ``True``) limits the type of map keys to bytes and str.
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`strict_map_key` (default: `True`) limits the type of map keys to bytes and str.
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While msgpack spec doesn't limit the types of the map keys,
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there is a risk of the hashdos.
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If you need to support other types for map keys, use ``strict_map_key=False``.
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If you need to support other types for map keys, use `strict_map_key=False`.
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### Performance tips
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CPython's GC starts when growing allocated object.
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This means unpacking may cause useless GC.
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You can use ``gc.disable()`` when unpacking large message.
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You can use `gc.disable()` when unpacking large message.
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List is the default sequence type of Python.
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But tuple is lighter than list.
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You can use ``use_list=False`` while unpacking when performance is important.
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You can use `use_list=False` while unpacking when performance is important.
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## Development
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