jsonpath-rw-ext 0.1.8

===============================
python-jsonpath-rw-ext
===============================

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Extensions for JSONPath RW

jsonpath-rw-ext extends json-path-rw capabilities by adding multiple extensions.
'len' that allows one to get the length of a list. 'sorted' that returns a sorted version
of a list, 'arithmetic' that permits one to make math operation between elements and
'filter' to select only certain elements of a list.

Each extensions will be proposed `upstream <https://github.com/kennknowles/python-jsonpath-rw>`__
and will stay here only if they are refused.

* Free software: Apache license
* Documentation: https://python-jsonpath-rw-ext.readthedocs.org/en/latest/
* Source: http://github.com/sileht/python-jsonpath-rw-ext


Quick Start
-----------

At the command line::

$ pip install jsonpath-rw-ext

Or, if you have virtualenvwrapper installed::

$ mkvirtualenv jsonpath-rw-ext
$ pip install jsonpath-rw-ext


To replace the jsonpath_rw parser by this one with::

import jsonpath_rw_ext
jsonpath_rw_ext.parse("$.foo").find(...)

Or::

from jsonpath_rw_ext import parser
parser.ExtentedJsonPathParser().parse("$.foo").find(...)


The jsonpath classes are not part of the public API, because the name/structure
can change when they will be implemented upstream. Only the syntax *shouldn't*
change.

Extensions
----------

+--------------+----------------------------------------------+
| name | Example |
+==============+==============================================+
| len | - $.objects.`len` |
+--------------+----------------------------------------------+
| sub | - $.field.`sub(/foo\\\\+(.*)/, \\\\1)` |
+--------------+----------------------------------------------+
| split | - $.field.`split(+, 2, -1)` |
| | - $.field.`split(sep, segement, maxsplit)` |
+--------------+----------------------------------------------+
| sorted | - $.objects.`sorted` |
| | - $.objects[\\some_field] |
| | - $.objects[\\some_field,/other_field] |
+--------------+----------------------------------------------+
| filter | - $.objects[?(@some_field > 5)] |
| | - $.objects[?some_field = "foobar")] |
| | - $.objects[?some_field > 5 & other < 2)] |
+--------------+----------------------------------------------+
| arithmetic | - $.foo + "_" + $.bar |
| (-+*/) | - $.foo * 12 |
| | - $.objects[*].cow + $.objects[*].cat |
+--------------+----------------------------------------------+

About arithmetic and string
---------------------------

Operations are done with python operators and allows types that python
allows, and return [] if the operation can be done due to incompatible types.

When operators are used, a jsonpath must be be fully defined otherwise
jsonpath-rw-ext can't known if the expression is a string or a jsonpath field,
in this case it will choice string as type.

Example with data::

{
'cow': 'foo',
'fish': 'bar'
}

| **cow + fish** returns **cowfish**
| **$.cow + $.fish** returns **foobar**
| **$.cow + "_" + $.fish** returns **foo_bar**
| **$.cow + "_" + fish** returns **foo_fish**

About arithmetic and list
-------------------------

Arithmetic can be used against two lists if they have the same size.

Example with data::

{'objects': [
{'cow': 2, 'cat': 3},
{'cow': 4, 'cat': 6}
]}

| **$.objects[\*].cow + $.objects[\*].cat** returns **[6, 9]**