py-context 0.3.1

Python dict with stacked context data

Python dict with stacked context data

• Free software: MIT license

• GitHub: https://github.com/dealertrack/py-context

Installing

You can install py-context using pip:

$ pip install py-context

Example

>>> context = Context({'user': 'Fred', 'city': 'Bedrock'})
>>> context['user']
'Fred'
>>> context['city']
'Bedrock'
>>> context.push({'user': 'Barney'})
>>> context['user']
'Barney'
>>> context['city']
'Bedrock'
>>> context.pop()
{'user': 'Barney'}
>>> context['user']
'Fred'

Context also supports signals. Signal handler can be attached globally:

>>> @context_key_changed.connect
... def handler(sender, context, key, new, old):
...     print(key, new, old)

>>> context = Context()
>>> context['hello'] = 'world'
hello world <Missing>

Or to individual context instances:

>>> def handler(sender, context, key, new, old):
...     print(key, new, old)
>>> context = Context()
>>> context_key_changed.connect(handler, sender=context)

Supported signals:

>>> @context_initialized.connect
... def handler(sender, context):
...     pass

>>> @pre_context_changed.connect
... def handler(sender, context):
...     pass

>>> @post_context_changed.connect
... def handler(sender, context):
...     pass

>>> @context_key_changed.connect
... def handler(sender, context, key, new, old):
...     pass

Additionally, ClassSignallingContext can be used to subscribe signals by sender classes, not instances:

>>> class TestContext(ClassSignallingContext):
...     pass
>>> def context_key_changed_handler(sender, context, key, new, old):
...     print(key, new, old)
>>> _ = context_key_changed.connect(context_key_changed_handler, sender=TestContext)

>>> context = Context()
>>> class_context = TestContext()

>>> context['foo'] = 'bar'
>>> class_context['foo'] = 'bar'
foo bar <Missing>

Testing

To run the tests you need to install testing requirements first:

$ make install

Then to run tests, you can use nosetests or simply use Makefile command:

$ nosetests -sv
# or
$ make test

History

0.3.1 (2018-04-11)

• Added support for *args, **kwargs in Context.push().

• Added __dir__ support.

0.3.0 (2018-02-16)

• Added signals support - context_initialized, pre_context_changed, post_context_changed and context_key_changed. See README for examples.

0.2.1 (2017-07-28)

• Excluding tests from being installed

0.2.0 (2017-05-11)

• Add attribute support

• Add make watch target

0.1.0 (2017-03-22)

• First release on PyPI.

Credits

Originally Context was taken from Genshi project. See LICENSE for copyright notices.

Development Lead

• Miroslav Shubernetskiy - https://github.com/miki725

Contributors

• Serkan Hosca - https://github.com/shosca

Copyright (C) 2006-2010 Edgewall Software

Copyright (C) 2017 Dealertrack Technologies, Inc.

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modification, are permitted provided that the following conditions
are met:

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   notice, this list of conditions and the following disclaimer in
   the documentation and/or other materials provided with the
   distribution.
3. The name of the author may not be used to endorse or promote
   products derived from this software without specific prior
   written permission.

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