django-imagekit: Generate predictable filenames in cache ¶

file settings.py:

#
#  ImageKit
#

#IMAGEKIT_DEFAULT_CACHEFILE_STRATEGY = 'imagekit.cachefiles.strategies.Optimistic'

# Generate predictable filenames in cache
#IMAGEKIT_SPEC_CACHEFILE_NAMER = 'imagekit.cachefiles.namers.source_name_as_path'
IMAGEKIT_SPEC_CACHEFILE_NAMER = 'main.imagekit_overrides.source_name_as_path'

where file main.imagekit_overrides.py is:

# adapted from "imagekit.cachefiles.namers.source_name_as_path.py"

from django.conf import settings
import os
from imagekit.utils import format_to_extension, suggest_extension


def my_get_hash(generator):
    name = ''
    try:
        processor = generator.processors[0]
        width = processor.width
        height = processor.height
        name = '%dx%d' % (width, height)
    except Exception as e:
        name = generator.get_hash()
    return name


def source_name_as_path(generator):
    """
    A namer that, given the following source file name::

        photos/thumbnails/bulldog.jpg

    will generate a name like this::

        /path/to/generated/images/photos/thumbnails/bulldog/5ff3233527c5ac3e4b596343b440ff67.jpg

    where "/path/to/generated/images/" is the value specified by the
    ``IMAGEKIT_CACHEFILE_DIR`` setting.

    """
    source_filename = getattr(generator.source, 'name', None)

    if source_filename is None or os.path.isabs(source_filename):
        # Generally, we put the file right in the cache file directory.
        dir = settings.IMAGEKIT_CACHEFILE_DIR
    else:
        # For source files with relative names (like Django media files),
        # use the source's name to create the new filename.
        dir = os.path.join(settings.IMAGEKIT_CACHEFILE_DIR,
                           os.path.splitext(source_filename)[0])

    ext = suggest_extension(source_filename or '', generator.format)
    #return os.path.normpath(os.path.join(dir, '%s%s' % (generator.get_hash(), ext)))
    return os.path.normpath(os.path.join(dir, '%s%s' % (my_get_hash(generator), ext)))