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| 1 | +.. encoding: utf-8 |
| 2 | +
|
| 3 | +Developer's guide |
| 4 | +================= |
| 5 | + |
| 6 | +Tarantool database basic concepts |
| 7 | +--------------------------------- |
| 8 | + |
| 9 | +To understand, what is "space", "tuple" and what basic operations are, |
| 10 | +refer to `Tarantool data model documentation`_. |
| 11 | + |
| 12 | +Field types |
| 13 | +----------- |
| 14 | + |
| 15 | +Tarantool uses `MessagePack`_ as a format for receiving requests and sending |
| 16 | +responses. Refer to `Lua versus MessagePack`_ to see how types are encoded |
| 17 | +and decoded. |
| 18 | + |
| 19 | +While working with Tarantool from Python with this connector, |
| 20 | +each request data is encoded to MessagePack and each response data |
| 21 | +is decoded from MessagePack with the `Python MessagePack`_ module. See its |
| 22 | +documentation to explore how basic types are encoded and decoded. |
| 23 | + |
| 24 | +There are several cases when you may tune up the behavior. |
| 25 | +Use :class:`tarantool.Connection` parameters to set Python MessagePack |
| 26 | +module options. |
| 27 | + |
| 28 | +Use :paramref:`~tarantool.Connection.params.encoding` to tune |
| 29 | +behavior for string encoding. |
| 30 | + |
| 31 | +``encoding='utf-8'`` (default): |
| 32 | + |
| 33 | + +--------------+----+----------------------------------+----+--------------+ |
| 34 | + | Python | -> | MessagePack (Tarantool/Lua) | -> | Python | |
| 35 | + +==============+====+==================================+====+==============+ |
| 36 | + | :obj:`str` | -> | `mp_str`_ (``string``) | -> | :obj:`str` | |
| 37 | + +--------------+----+----------------------------------+----+--------------+ |
| 38 | + | :obj:`bytes` | -> | `mp_bin`_ (``binary``/``cdata``) | -> | :obj:`bytes` | |
| 39 | + +--------------+----+----------------------------------+----+--------------+ |
| 40 | + |
| 41 | +``encoding=None`` (work with non-UTF8 strings): |
| 42 | + |
| 43 | + +--------------+----+----------------------------------+----+--------------+ |
| 44 | + | Python | -> | MessagePack (Tarantool/Lua) | -> | Python | |
| 45 | + +==============+====+==================================+====+==============+ |
| 46 | + | :obj:`bytes` | -> | `mp_str`_ (``string``) | -> | :obj:`bytes` | |
| 47 | + +--------------+----+----------------------------------+----+--------------+ |
| 48 | + | :obj:`str` | -> | `mp_str`_ (``string``) | -> | :obj:`bytes` | |
| 49 | + +--------------+----+----------------------------------+----+--------------+ |
| 50 | + | | -> | `mp_bin`_ (``binary``/``cdata``) | -> | :obj:`bytes` | |
| 51 | + +--------------+----+----------------------------------+----+--------------+ |
| 52 | + |
| 53 | +Use :paramref:`~tarantool.Connection.params.use_list` to tune |
| 54 | +behavior for `mp_array`_ (Lua ``table``) decoding. |
| 55 | + |
| 56 | +``use_list='True'`` (default): |
| 57 | + |
| 58 | + +--------------+----+-----------------------------+----+--------------+ |
| 59 | + | Python | -> | MessagePack (Tarantool/Lua) | -> | Python | |
| 60 | + +==============+====+=============================+====+==============+ |
| 61 | + | :obj:`list` | -> | `mp_array`_ (``table``) | -> | :obj:`list` | |
| 62 | + +--------------+----+-----------------------------+----+--------------+ |
| 63 | + | :obj:`tuple` | -> | `mp_array`_ (``table``) | -> | :obj:`list` | |
| 64 | + +--------------+----+-----------------------------+----+--------------+ |
| 65 | + |
| 66 | +``use_list='False'``: |
| 67 | + |
| 68 | + +--------------+----+-----------------------------+----+--------------+ |
| 69 | + | Python | -> | MessagePack (Tarantool/Lua) | -> | Python | |
| 70 | + +==============+====+=============================+====+==============+ |
| 71 | + | :obj:`list` | -> | `mp_array`_ (``table``) | -> | :obj:`tuple` | |
| 72 | + +--------------+----+-----------------------------+----+--------------+ |
| 73 | + | :obj:`tuple` | -> | `mp_array`_ (``table``) | -> | :obj:`tuple` | |
| 74 | + +--------------+----+-----------------------------+----+--------------+ |
| 75 | + |
| 76 | +Tarantool implements several `extension types`_. In Python, |
| 77 | +they are represented with in-built and custom types: |
| 78 | + |
| 79 | + +-----------------------------+----+-------------+----+-----------------------------+ |
| 80 | + | Python | -> | Tarantool | -> | Python | |
| 81 | + +=============================+====+=============+====+=============================+ |
| 82 | + | :obj:`decimal.Decimal` | -> | `DECIMAL`_ | -> | :obj:`decimal.Decimal` | |
| 83 | + +-----------------------------+----+-------------+----+-----------------------------+ |
| 84 | + | :obj:`uuid.UUID` | -> | `UUID`_ | -> | :obj:`uuid.UUID` | |
| 85 | + +-----------------------------+----+-------------+----+-----------------------------+ |
| 86 | + | :class:`tarantool.Datetime` | -> | `DATETIME`_ | -> | :class:`tarantool.Datetime` | |
| 87 | + +-----------------------------+----+-------------+----+-----------------------------+ |
| 88 | + | :class:`tarantool.Interval` | -> | `INTERVAL`_ | -> | :class:`tarantool.Interval` | |
| 89 | + +-----------------------------+----+-------------+----+-----------------------------+ |
| 90 | + |
| 91 | +Request response |
| 92 | +---------------- |
| 93 | + |
| 94 | +Server requests (except for :meth:`~tarantool.Connection.ping`) |
| 95 | +return :class:`~tarantool.response.Response` instance in case |
| 96 | +of success. |
| 97 | + |
| 98 | +:class:`~tarantool.response.Response` is inherited from |
| 99 | +:class:`collections.abc.Sequence`, so you can index response data |
| 100 | +and iterate through it as with any other serializable object. |
| 101 | + |
| 102 | +.. _Tarantool data model documentation: https://www.tarantool.io/en/doc/latest/concepts/data_model/ |
| 103 | +.. _MessagePack: https://msgpack.org/ |
| 104 | +.. _Lua versus MessagePack: https://www.tarantool.io/en/doc/latest/concepts/data_model/value_store/#lua-versus-msgpack |
| 105 | +.. _Python MessagePack: https://pypi.org/project/msgpack/ |
| 106 | +.. _mp_str: https://github.com/msgpack/msgpack/blob/master/spec.md#str-format-family |
| 107 | +.. _mp_bin: https://github.com/msgpack/msgpack/blob/master/spec.md#bin-format-family |
| 108 | +.. _mp_array: https://github.com/msgpack/msgpack/blob/master/spec.md#array-format-family |
| 109 | +.. _extension types: https://www.tarantool.io/en/doc/latest/dev_guide/internals/msgpack_extensions/ |
| 110 | +.. _DECIMAL: https://www.tarantool.io/en/doc/latest/dev_guide/internals/msgpack_extensions/#the-decimal-type |
| 111 | +.. _UUID: https://www.tarantool.io/en/doc/latest/dev_guide/internals/msgpack_extensions/#the-uuid-type |
| 112 | +.. _DATETIME: https://www.tarantool.io/en/doc/latest/dev_guide/internals/msgpack_extensions/#the-datetime-type |
| 113 | +.. _INTERVAL: https://www.tarantool.io/en/doc/latest/dev_guide/internals/msgpack_extensions/#the-interval-type |
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