Merge pull request #17 from relekang/django-filters

Add django filters for markdown and html

docs/creating-thumbnails.rst

@@ -28,3 +28,46 @@ name for the thumbnail with an ``as`` keyword as shown in the example below.
     {% get_thumbnail "image.jpg" "400x400" crop="center" as thumbnail %}
     <img src="{{ thumbnail.url }}" alt="The thumbnail" style="width: {{ thumbnail.width }} />
 
+
+Filters
+^^^^^^^
+
+.. autofunction:: thumbnails.templatetags.thumbnails.markdown_thumbnails
+
+.. code-block:: html+django
+
+    {% load thumbnails %}
+
+    {{ content|markdown_thumbnails }}
+
+.. autofunction:: thumbnails.templatetags.thumbnails.html_thumbnails
+
+.. code-block:: html+django
+
+    {% load thumbnails %}
+
+    {{ content|html_thumbnails }}
+
+.. autofunction:: thumbnails.templatetags.thumbnails.safe_html_thumbnails
+
+.. code-block:: html+django
+
+    {% load thumbnails %}
+
+    {{ content|safe_html_thumbnails }}
+
+**Creating custom text filters**
+
+It is possible to create custom text filters by utilizing the ``text_filter`` function described
+below.
+
+.. autofunction:: thumbnails.templatetags.thumbnails.text_filter
+
+Below is the code for the ``html_thumbnails``-filter shown as an example of how to use
+``text_filter``.
+
+.. code-block:: python
+
+    @register.filter
+    def html_thumbnails(value):
+        return mark_safe(text_filter('<img(?: alt="(%(caption)s)?")? src="(%(image)s)"', value))

docs/settings.rst

@@ -71,6 +71,18 @@ Image options
       an alternative version with the number as a proportions-factor.
     | **Default:** ``[2]``
 
+
+Templatetags and filters
+------------------------
+
+.. attribute:: THUMBNAIL_FILTER_OPTIONS
+    :noindex:
+
+        | The options passed into ``get_thumbnail`` by the Markdown and HTML filter. It can contain
+          all options that is supported by ``get_thumbnails``, however size is required.
+        | **Default:** ``{'size': '500'}``
+
+
 Dummy thumbnails
 ----------------
 

tests/test_templatetags.py

@@ -1,6 +1,8 @@
 # -*- coding: utf-8 -*-
 import unittest
 
+from thumbnails import settings
+
 from .compat import mock
 from .utils import has_installed
 
@@ -55,3 +57,55 @@ def test_get_thumbnail_templatetag_with_FileField_as_source(self, mock_get_thumb
         }))
 
         mock_get_thumbnail.assert_called_once_with(_file, '200x200')
+
+
+@mock.patch('{}.get_thumbnail'.format(settings.THUMBNAIL_ENGINE), lambda *args: None)
+@mock.patch('thumbnails.images.Thumbnail.save', lambda *args: None)
+@mock.patch('thumbnails.images.Thumbnail.save_alternative_resolution', lambda *args: None)
+@unittest.skipIf(not has_installed('django'), 'Django not installed')
+class FilterTestCase(unittest.TestCase):
+
+    def setUp(self):
+        self.MARKDOWN_TEMPLATE = Template('{% load thumbnails %}{{ text|markdown_thumbnails }}')
+        self.HTML_TEMPLATE = Template('{% load thumbnails %}{{ text|html_thumbnails }}')
+        self.SAFE_HTML_TEMPLATE = Template('{% load thumbnails %}{{ text|safe_html_thumbnails }}')
+
+    def test_markdown_filter(self):
+        self.assertEqual(self.MARKDOWN_TEMPLATE.render(Context({
+            'text': 'image: ![Title](/image.jpg)'
+        })), 'image: ![Title](thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e.jpg)')
+
+        self.assertEqual(self.MARKDOWN_TEMPLATE.render(Context({
+            'text': 'image: ![](/image.jpg)'
+        })), 'image: ![](thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e.jpg)')
+
+    def test_html_filter(self):
+        self.assertEqual(self.HTML_TEMPLATE.render(Context({
+            'text': 'image: <img src="/image.jpg" alt="Title" />'
+        })), 'image: <img src="thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e.jpg"'
+             ' alt="Title" />')
+
+        self.assertEqual(self.HTML_TEMPLATE.render(Context({
+            'text': 'image: <img src="/image.jpg" alt="" />'
+        })), 'image: <img src="thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e.jpg"'
+             ' alt="" />')
+
+        self.assertEqual(self.HTML_TEMPLATE.render(Context({
+            'text': 'image: <img src="/image.jpg" />'
+        })), 'image: <img src="thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e.jpg" />')
+
+    def test_safe_html_filter(self):
+        self.assertEqual(self.SAFE_HTML_TEMPLATE.render(Context({
+            'text': 'image: <img src="/image.jpg" alt="Title" />'
+        })), 'image: &lt;img src=&quot;thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e'
+             '.jpg&quot; alt=&quot;Title&quot; /&gt;')
+
+        self.assertEqual(self.SAFE_HTML_TEMPLATE.render(Context({
+            'text': 'image: <img src="/image.jpg" alt="" />'
+        })), 'image: &lt;img src=&quot;thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e'
+             '.jpg&quot; alt=&quot;&quot; /&gt;')
+
+        self.assertEqual(self.SAFE_HTML_TEMPLATE.render(Context({
+            'text': 'image: <img src="/image.jpg" />'
+        })), 'image: &lt;img src=&quot;thumbnails-cache/09a/e5965fd6bcafba14e3e696059acfa3db6ca8e'
+             '.jpg&quot; /&gt;')

thumbnails/conf/defaults.py

@@ -14,5 +14,8 @@
 THUMBNAIL_COLORMODE = 'RGB'
 THUMBNAIL_ALTERNATIVE_RESOLUTIONS = [2]
 
+THUMBNAIL_FILTER_SIZE = '500'
+THUMBNAIL_FILTER_OPTIONS = {'size': '500'}
+
 THUMBNAIL_DUMMY = False
 THUMBNAIL_DUMMY_URL = 'http://puppies.lkng.me/{}x{}'

thumbnails/templatetags/thumbnails.py

@@ -6,6 +6,9 @@
 from django import template
 from django.template import Library
 from django.template.base import TemplateSyntaxError
+from django.utils.safestring import mark_safe
+
+from thumbnails import settings
 
 register = Library()
 
@@ -49,3 +52,55 @@ def render(self, context):
             raise TemplateSyntaxError()
 
         return ''
+
+
+def text_filter(regex_base, value):
+    """
+    A text-filter helper, used in ``markdown_thumbnails``-filter and ``html_thumbnails``-filter.
+    It can be used to build custom thumbnail text-filters.
+
+    :param regex_base: A string with a regex that contains ``%(captions)s`` and ``%(image)s`` where
+                       the caption and image should be.
+    :param value: String of text in which the source URLs can be found.
+    :return: A string ready to be put in a template.
+    """
+    from thumbnails import get_thumbnail
+    regex = regex_base % {
+        'caption': '[a-zA-Z0-9\.\,:;/_ \(\)\-\!\?\"]+',
+        'image': '[a-zA-Z0-9\.:/_\-\% ]+'
+    }
+    images = re.findall(regex, value)
+
+    for i in images:
+        image_url = i[1]
+        image = get_thumbnail(
+            image_url,
+            **settings.THUMBNAIL_FILTER_OPTIONS
+        )
+        value = value.replace(i[1], image.url)
+
+    return value
+
+
+@register.filter
+def markdown_thumbnails(value):
+    """
+    Markdown filter that replaces all images with thumbnails.
+    """
+    return text_filter('!\[(%(caption)s)?\][ ]?\((%(image)s)\)', value)
+
+
+@register.filter
+def safe_html_thumbnails(value):
+    """
+    HTML filter that replaces all images with thumbnails, the returned string is not marked as safe.
+    """
+    return text_filter('<img(?: alt="(%(caption)s)?")? src="(%(image)s)"', value)
+
+
+@register.filter
+def html_thumbnails(value):
+    """
+    HTML filter that replaces all images with thumbnails, the returned string is marked as safe.
+    """
+    return mark_safe(text_filter('<img(?: alt="(%(caption)s)?")? src="(%(image)s)"', value))