initial commit

Author: Kub-AT

.gitignore

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+*.py[cod]
+__pycache__
+
+# C extensions
+*.so
+
+# Packages
+*.egg
+*.egg-info
+dist
+build
+eggs
+parts
+var
+sdist
+develop-eggs
+.installed.cfg
+lib
+lib64
+
+# Installer logs
+pip-log.txt
+
+# Unit test / coverage reports
+.coverage
+.tox
+nosetests.xml
+
+# Mr Developer
+.mr.developer.cfg
+.project
+.pydevproject
+
+# Backup versions of files [Kw’s scheme]
+o.*
+
+# GitHub token file
+.pypt/gh-token

.travis.yml

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+language: python
+sudo: false
+python:
+ - "2.7"
+ - "3.3"
+ - "3.4"
+ - "3.5"
+ - "pypy"
+
+install:
+ - "pip install -r requirements.txt"
+ - "pip install ."
+
+script:
+  - "py.test --cov cache_fallback --cov-report term-missing tests/"
+
+notifications:
+  email:
+    on_success: change
+    on_failure: always

AUTHORS

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+Jakub S

LICENSE

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+MIT License
+
+Copyright (c) 2016 Jakub S.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

MANIFEST.in

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+graft cache_fallback
+graft docs
+graft tests
+include README.rst AUTHORS LICENSE CHANGELOG.rst setup.py setup.cfg requirements.txt
+global-exclude __pycache__ *.pyc

README.rst

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+==============================================================================
+Django Cache Fallback.
+==============================================================================
+:Info: This is the README file for Django Cache Fallback.
+:Author: Jakub S
+
+.. index: README
+.. image:: https://travis-ci.org/Kub-AT/django-cache-fallback.svg?branch=master
+   :target: https://travis-ci.org/Kub-AT/django-cache-fallback
+
+PURPOSE
+-------
+Allows you to set fallback cache backend. 
+The data is not shared between cache backends.
+Example: Memcached is not available, backend switch to fallback. Site may slow down (cache have to be set)
+but will not rise an error (watch your logs)
+
+INSTALLATION
+------------
+pip install django-cache-fallback
+
+INSTALLED_APPS = (
+    ...
+    'cache_fallback',
+)
+
+USAGE
+-----
+Usage example PyLibMCCache + LocMemCache
+
+.. code:: python
+
+    CACHES = {
+        'default': {
+            'BACKEND': 'cache_fallback.FallbackCache',
+        },
+
+        'main_cache': {
+            'BACKEND': 'django.core.cache.backends.memcached.PyLibMCCache',
+            'LOCATION': '/tmp/memcached.sock',
+            'TIMEOUT': 500,
+        },
+        'fallback_cache': {
+            'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
+            'LOCATION': 'unique'
+        }
+
+    }
+
+NOTES
+-----

cache_fallback/__init__.py

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+## -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from .cache import FallbackCache
+
+__title__ = 'Django Cache Fallback'
+
+__all__ = (FallbackCache, )
+

cache_fallback/cache.py

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+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+import logging
+from django.core import signals
+from django.core.cache.backends.base import BaseCache
+
+logging.basicConfig()
+logger = logging.getLogger(__name__)
+
+
+
+def get_cache(backend, **kwargs):
+    """
+    Compatibilty wrapper for getting Django's cache backend instance
+
+    original source:
+    https://github.com/vstoykov/django-imagekit/commit/c26f8a0538778969a64ee471ce99b25a04865a8e
+    """
+    from django.core import cache
+
+    # Django < 1.7
+    if not hasattr(cache, '_create_cache'):
+        return cache.get_cache(backend, **kwargs)
+
+    cache = cache._create_cache(backend, **kwargs)
+    # Some caches -- python-memcached in particular -- need to do a cleanup at the
+    # end of a request cycle. If not implemented in a particular backend
+    # cache.close is a no-op. Not available in Django 1.5
+    if hasattr(cache, 'close'):
+        signals.request_finished.connect(cache.close)
+    return cache
+
+
+class FallbackCache(BaseCache):
+    _cache = None
+    _cache_fallback = None
+
+    def __init__(self, host, *args, **kwargs):
+        BaseCache.__init__(self, *args, **kwargs)
+        self._cache = get_cache('main_cache')
+        self._cache_fallback = get_cache('fallback_cache')
+
+    def _call_with_fallback(self, method, *args, **kwargs):
+        try:
+            return getattr(self._cache, method)(*args, **kwargs)
+        except Exception as e:
+            logger.exception(e)
+            return getattr(self._cache_fallback, method)(*args, **kwargs)
+
+    def add(self, key, value, timeout=None, version=None):
+        return self._call_with_fallback('add', key, value, timeout=None, version=None)
+
+    def get(self, key, default=None, version=None):
+        return self._call_with_fallback('get', key, default=default, version=version)
+
+    def set(self, key, value, timeout=None, version=None, client=None):
+        return self._call_with_fallback('set', key, value, timeout=timeout, version=version)
+
+    def delete(self, key, version=None):
+        return self._call_with_fallback('delete', key, version=version)
+
+    def clear(self):
+        return self._call_with_fallback('clear')

requirements.txt

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+django
+pytest
+coverage
+pytest-cov

setup.cfg

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+[wheel]
+universal = 1
+
+[tool:pytest]
+norecursedirs = .git
+addopts = --cov=cache_fallback --cov-report term-missing
+
+[coverage:run]
+branch = True
+omit = tests/*