Image sizer plugin: add image dimensions in HTML code

This plugin adds `width` and `height` tags to `img` when they are not
present. It also adds them when only one of them is present
(respecting proportions).

hyde/ext/plugins/images.py

@@ -0,0 +1,86 @@
+# -*- coding: utf-8 -*-
+"""
+Contains classes to handle images related things
+"""
+
+from hyde.plugin import Plugin
+
+import re
+import Image
+from BeautifulSoup import BeautifulSoup
+
+class ImageSizerPlugin(Plugin):
+    """
+    Each HTML page is modified to add width and height for images if
+    they are not already specified.
+    """
+
+    def __init__(self, site):
+        super(ImageSizerPlugin, self).__init__(site)
+        self.cache = {}
+
+    def text_resource_complete(self, resource, text):
+        """
+        When the resource is generated, search for img tag and specify
+        their sizes.
+        """
+        try:
+            mode = self.site.config.mode
+        except AttributeError:
+            mode = "production"
+
+        if not resource.source_file.kind == 'html':
+            return
+
+        if mode.startswith('dev'):
+            self.logger.debug("Skipping sizer in development mode.")
+            return
+
+        soup = BeautifulSoup(text)
+        for img in soup.findAll('img'):
+            if img.has_key('width') and img.has_key('height'):
+                continue
+            if not img.has_key('src'):
+                self.logger.warn("[%s] has an img tag without src attribute" % resource)
+                continue
+            if not img['src'] in self.cache:
+                if not re.match(r"(/[^/]|[^/]).*", img['src']):
+                    # Not a local link
+                    continue
+                if img['src'].startswith("/"):
+                    # Absolute resource
+                    path = img['src'].lstrip("/")
+                    image = self.site.content.resource_from_relative_deploy_path(path)
+                else:
+                    # Relative resource
+                    path = resource.node.source_folder.child(img['src'])
+                    image = self.site.content.resource_from_path(path)
+                if image is None:
+                    self.logger.warn(
+                        "[%s] has an unknown image" % resource)
+                    continue
+                if image.source_file.kind not in ['png', 'jpg', 'jpeg', 'gif']:
+                    self.logger.warn(
+                        "[%s] has an img tag not linking to an image" % resource)
+                    continue
+                # Now, get the size of the image
+                try:
+                    self.cache[img['src']] = Image.open(image.path).size
+                except IOError:
+                    self.logger.warn(
+                        "Unable to process image [%s]" % image)
+                    self.cache[img['src']] = (None, None)
+                    continue
+                self.logger.debug("Image [%s] is %s" % (img['src'],
+                                                        self.cache[img['src']]))
+            width, height = self.cache[img['src']]
+            if width is None:
+                continue
+            if img.has_key('width'):
+                height = int(img['width'])*height/width
+                width = int(img['width'])
+            elif img.has_key('height'):
+                width = int(img['height'])*width/height
+                height = int(img['height'])
+            img['height'], img['width'] = height, width
+        return unicode(soup)

hyde/tests/ext/test_images.py

@@ -0,0 +1,84 @@
+# -*- coding: utf-8 -*-
+"""
+Use nose
+`$ pip install nose`
+`$ nosetests`
+"""
+from hyde.fs import File, Folder
+from hyde.generator import Generator
+from hyde.site import Site
+
+from pyquery import PyQuery
+
+TEST_SITE = File(__file__).parent.parent.child_folder('_test')
+IMAGE_SOURCE = File(__file__).parent.child_folder('optipng')
+IMAGE_NAME = "hyde-lt-b.png"
+IMAGE_SIZE = (538, 132)
+
+class TestImageSizer(object):
+
+    def setUp(self):
+        TEST_SITE.make()
+        TEST_SITE.parent.child_folder(
+                    'sites/test_jinja').copy_contents_to(TEST_SITE)
+        IMAGES = TEST_SITE.child_folder('content/media/img')
+        IMAGES.make()
+        IMAGE_SOURCE.copy_contents_to(IMAGES)
+
+    def tearDown(self):
+        TEST_SITE.delete()
+
+    def _generic_test_image(self, text):
+        site = Site(TEST_SITE)
+        site.config.mode = "production"
+        site.config.plugins = ['hyde.ext.plugins.images.ImageSizerPlugin']
+        tlink = File(site.content.source_folder.child('timg.html'))
+        tlink.write(text)
+        gen = Generator(site)
+        gen.generate_all()
+        f = File(site.config.deploy_root_path.child(tlink.name))
+        assert f.exists
+        html = f.read_all()
+        assert html
+        print html
+        return html
+
+    def test_size_image(self):
+        text = u"""
+<img src="/media/img/%s">
+""" % IMAGE_NAME
+        html = self._generic_test_image(text)
+        assert ' width="%d"' % IMAGE_SIZE[0] in html
+        assert ' height="%d"' % IMAGE_SIZE[1] in html
+
+    def test_size_image_relative(self):
+        text = u"""
+<img src="media/img/%s">
+""" % IMAGE_NAME
+        html = self._generic_test_image(text)
+        assert ' width="%d"' % IMAGE_SIZE[0] in html
+        assert ' height="%d"' % IMAGE_SIZE[1] in html
+
+    def test_size_image_no_resize(self):
+        text = u"""
+<img src="/media/img/%s" width="2000" height="150">
+""" % IMAGE_NAME
+        html = self._generic_test_image(text)
+        assert ' width="%d"' % IMAGE_SIZE[0] not in html
+        assert ' height="%d"' % IMAGE_SIZE[1] not in html
+
+    def test_size_image_size_proportional(self):
+        text = u"""
+<img src="/media/img/%s" width="%d">
+""" % (IMAGE_NAME,  IMAGE_SIZE[0]*2)
+        html = self._generic_test_image(text)
+        assert ' width="%d"' % (IMAGE_SIZE[0]*2) in html
+        assert ' height="%d"' % (IMAGE_SIZE[1]*2) in html
+
+    def test_size_image_not_exists(self):
+        text = u"""
+<img src="/media/img/hyde-logo-no.png">
+"""
+        html = self._generic_test_image(text)
+
+