django-heroku-memcacheify 0.4

# django-heroku-memcacheify

Automatic Django memcached configuration on Heroku.




## Install

To install ``django-heroku-memcacheify``, simply run
``pip install django-heroku-memcacheify`` and you'll get the latest version
installed automatically.

**NOTE**: If you'd like to install this locally, you'll need to have the
``libmemcached-dev`` libraries installed for this to compile properly. On
Debian and Ubuntu you can install this by running ``sudo aptitude -y install
libmemcached-dev``. If you're using a Mac, you can use
[homebrew](http://mxcl.github.com/homebrew/) and run ``brew install libmemcached``.


## Usage

Modify your Django ``settings.py`` file, and set:

``` python
from memcacheify import memcacheify

CACHES = memcacheify()
```

Next, edit your ``requirements.txt`` file (which Heroku reads) and add
``pylibmc==1.2.3`` to the bottom of the file. This is required for Heroku to
detect the necessary C dependencies and 'bootstrap' your application. This requirement
has to be in the root ``requirements.txt`` file, not in any imported requirements.
([Solution from Stack Overflow](http://stackoverflow.com/questions/11507639/memcached-on-heroku-w-django-cant-install-pylibmc-memcacheify/11587142#11587142))

Assuming you have a memcache server available to your application on Heroku, it
will instantly be available. If you have no memcache addon provisioned for your
app, ``memcacheify`` will default to using local memory caching as a backup :)


## Heroku Setup

Now that you've got Django configured to use memcache, all you need to do is
install one of the two excellent memcache addons that Heroku provides!

- [Memcache](https://addons.heroku.com/memcache) - Been around longer, but
pretty expensive, or
- [MemCachier](https://addons.heroku.com/memcachier) - Newer, less expensive.

Let's say I want to install the ``memcachier`` addon, I could simply run:

``` bash
$ heroku addons:add memcachier:25
$ heroku config
...
MEMCACHIER_SERVERS => memcachier1.example.net
MEMCACHIER_USERNAME => bobslob
MEMCACHIER_PASSWORD => l0nGr4ndoMstr1Ngo5strang3CHaR4cteRS
...
```

The example above will provision a *free* 25m memcache server for your
application. Assuming everything worked, ``heroku config``'s output should show
that you now have 3 new environment variables set.


## Testing Your Cache

If you don't trust me, and want to make sure your caching is working as
expected, you may do the following:

``` bash
$ heroku run python manage.py shell
Running python manage.py shell attached to terminal... up, run.1
Python 2.7.2 (default, Oct 31 2011, 16:22:04)
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from django.core.cache import cache
>>> cache.set('memcache', 'ify!')
True
>>> cache.get('memcache')
'ify!'
>>>
```

Assuming everything is working, you should be able to set and retrieve cache
keys.


## References

If you're confused, you should probably read:

- [Heroku's Getting Started Guide](http://devcenter.heroku.com/articles/django)
- [Heroku's memcache Addon Documentation](https://devcenter.heroku.com/articles/memcache#using_memcache_from_python)
- [Heroku's memcachier Addon Documentation](https://devcenter.heroku.com/articles/memcachier)


## Tests

[](http://travis-ci.org/rdegges/django-heroku-memcacheify)

Want to run the tests? No problem:

``` bash
$ git clone git://github.com/rdegges/django-heroku-memcacheify.git
$ cd django-heroku-memcacheify
$ python setup.py develop
...
$ pip install -r requirements.txt # Install test dependencies.
$ nosetests
.............
----------------------------------------------------------------------
Ran 13 tests in 0.166s

OK
```


## Changelog

v0.4: 12-5-2012

- Update which allows memcachier users to support multiple servers >:)
Thanks @alexlod!

v0.3: 6-27-2012

- Fixing broken memcachier support.

v0.2: 5-22-2012

- Adding support for memcachier Heroku addon.
- Updating documentation.
- Refactoring implementation for clarity.
- Adding better tests.

v0.1: 5-2-2012

- Initial release!