:mod:`formalchemy.ext.fsblob` -- File system renderer
=====================================================

This extension is used to store binary files/images on filesystem and only
store the file path in the database.

This page present a Pylons integration but it should work on most framework.

.. automodule:: formalchemy.ext.fsblob

Renderers
---------

.. autoclass:: FileFieldRenderer
   :members:

.. autoclass:: ImageFieldRenderer
   :members:


Usage
-----

You must override the `storage_path` attribute:

.. literalinclude:: ../../pylonsapp/pylonsapp/forms/fsblob.py

As you can see, you can use it like all :mod:`~formalchemy.fields` in the
`.configure` method.

Validators
----------

Work like all :mod:`~formalchemy.validators`.

.. autofunction:: file_extension

    >>> from formalchemy.ext.fsblob import file_extension
    >>> validator = file_extension(extensions=['txt'])
    >>> validator('my image.txt')

    >>> validator('my image.png') # doctest: +ELLIPSIS
    Traceback (most recent call last):
    ...
    ValidationError: Invalid file extension. Must be txt


.. autofunction:: image_extension

    >>> from formalchemy.ext.fsblob import image_extension
    >>> validator = image_extension()
    >>> validator('my image.png')

    >>> validator('my image.txt') # doctest: +ELLIPSIS
    Traceback (most recent call last):
    ...
    ValidationError: Invalid image file. Must be jpeg, jpg, gif, png

Sample app 
----------

You can have a look at the complete `source
<http://code.google.com/p/formalchemy/source/browse/#svn/trunk/pylonsapp>`_ of
the application used for FA's testing.