Refactor: guess_mimetype()

sphinx/environment.py

@@ -16,7 +16,6 @@ import time
 import types
 import bisect
 import codecs
-import imghdr
 import string
 import unicodedata
 from os import path
@@ -41,6 +40,7 @@ from sphinx.util import url_re, get_matching_docs, docname_join, split_into, \
 from sphinx.util.nodes import clean_astext, make_refnode, WarningStream, is_translatable
 from sphinx.util.osutil import SEP, getcwd, fs_encoding, ensuredir
 from sphinx.util.i18n import find_catalog_files
+from sphinx.util.images import guess_mimetype
 from sphinx.util.console import bold, purple
 from sphinx.util.matching import compile_matchers
 from sphinx.util.parallel import ParallelTasks, parallel_available, make_chunks
@@ -902,24 +902,15 @@ class BuildEnvironment:
                 for filename in glob(full_imgpath):
                     new_imgpath = relative_path(path.join(self.srcdir, 'dummy'),
                                                 filename)
-                    if filename.lower().endswith('.pdf'):
-                        candidates['application/pdf'] = new_imgpath
-                    elif filename.lower().endswith('.svg'):
-                        candidates['image/svg+xml'] = new_imgpath
-                    else:
-                        try:
-                            f = open(filename, 'rb')
-                            try:
-                                imgtype = imghdr.what(f)
-                            finally:
-                                f.close()
-                        except (OSError, IOError) as err:
-                            self.warn_node('image file %s not readable: %s' %
-                                           (filename, err), node)
-                        if imgtype:
-                            candidates['image/' + imgtype] = new_imgpath
+                    try:
+                        mimetype = guess_mimetype(filename)
+                        candidates[mimetype] = new_imgpath
+                    except (OSError, IOError) as err:
+                        self.warn_node('image file %s not readable: %s' %
+                                       (filename, err), node)
             else:
                 candidates['*'] = rel_imgpath
+
             # map image paths to unique image names (so that they can be put
             # into a single directory)
             for imgpath in itervalues(candidates):

sphinx/util/images.py

@@ -9,7 +9,9 @@
     :license: BSD, see LICENSE for details.
 """
 
+import imghdr
 import imagesize
+from os import path
 
 try:
     from PIL import Image        # check for the Python Imaging Library
@@ -19,6 +21,11 @@ except ImportError:
     except ImportError:
         Image = None
 
+mime_suffixes = {
+    '.pdf': 'application/pdf',
+    '.svg': 'image/svg+xml',
+}
+
 
 def get_image_size(filename):
     try:
@@ -37,3 +44,16 @@ def get_image_size(filename):
         return size
     except:
         return None
+
+
+def guess_mimetype(filename):
+    _, ext = path.splitext(filename)
+    if ext in mime_suffixes:
+        return mime_suffixes[ext]
+    else:
+        with open(filename, 'rb') as f:
+            imgtype = imghdr.what(f)
+            if imgtype:
+                return 'image/' + imgtype
+
+    return None