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.. -*- coding: utf-8 -*-
.. :Project: python-rapidjson -- dump function documentation
.. :Author: Lele Gaifax <lele@metapensiero.it>
.. :License: MIT License
.. :Copyright: © 2017, 2018, 2019, 2020 Lele Gaifax
..
=================
dump() function
=================
.. currentmodule:: rapidjson
.. testsetup::
import io
from rapidjson import dump, dumps
.. function:: dump(obj, stream, *, skipkeys=False, ensure_ascii=True, \
write_mode=WM_COMPACT, indent=4, default=None, sort_keys=False, \
number_mode=None, datetime_mode=None, uuid_mode=None, \
bytes_mode=BM_UTF8, iterable_mode=IM_ANY_ITERABLE, \
mapping_mode=MM_ANY_MAPPING, chunk_size=65536, allow_nan=True)
Encode given Python `obj` instance into a ``JSON`` stream.
:param obj: the value to be serialized
:param stream: a *file-like* instance
:param bool skipkeys: whether skip invalid :class:`dict` keys
:param bool ensure_ascii: whether the output should contain only ASCII
characters
:param int write_mode: enable particular pretty print behaviors
:param indent: indentation width or string to produce pretty printed JSON
:param callable default: a function that gets called for objects that can't
otherwise be serialized
:param bool sort_keys: whether dictionary keys should be sorted
alphabetically
:param int number_mode: enable particular behaviors in handling numbers
:param int datetime_mode: how should :class:`datetime`, :class:`time` and
:class:`date` instances be handled
:param int uuid_mode: how should :class:`UUID` instances be handled
:param int bytes_mode: how should :class:`bytes` instances be handled
:param int iterable_mode: how should `iterable` values be handled
:param int mapping_mode: how should `mapping` values be handled
:param int chunk_size: write the stream in chunks of this size at a time
:param bool allow_nan: *compatibility* flag equivalent to ``number_mode=NM_NAN``
The function has the same behaviour as :func:`dumps()`, except that it requires
an additional mandatory parameter, a *file-like* writable `stream` instance:
.. doctest::
>>> stream = io.BytesIO()
>>> dump('bar', stream)
>>> stream.getvalue()
b'"bar"'
The target may also be a text stream\ [#]_:
.. doctest::
>>> stream = io.StringIO()
>>> dump(r'¯\_(ツ)_/¯', stream)
>>> stream.getvalue() == dumps(r'¯\_(ツ)_/¯')
True
.. rubric:: `chunk_size`
The `chunk_size` argument determines the size of the *buffer* used to feed the
*stream*: the greater the value, the fewer calls will be made to its ``write()``
method.
Consult the :func:`dumps()` documentation for details on all other arguments.
.. [#] A *text stream* is recognized by checking the presence of an ``encoding`` member
attribute on the instance.
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