Refactor image resize code, with better filenames (#261)

[mediagoblin.git] / mediagoblin / media_types / image / processing.py

diff --git a/mediagoblin/media_types/image/processing.py b/mediagoblin/media_types/image/processing.py
index b61e717d60c8fd1a851b99caee045eef08c6fef0..2a00606a3f743d5f8693ea6084e541436cbd14cf 100644 (file)
--- a/mediagoblin/media_types/image/processing.py
+++ b/mediagoblin/media_types/image/processing.py
@@ -23,6 +23,46 @@ from mediagoblin.processing import BadMediaFail, \
 from mediagoblin.tools.exif import exif_fix_image_orientation, \
     extract_exif, clean_exif, get_gps_data, get_useful
 
+MAX_FILENAME_LENGTH = 255  # the limit in VFAT -- seems like a good baseline
+
+def resize_image(entry, filename, basename, file_tail, exif_tags, workdir,
+                 new_size, size_limits=None):
+    """Store a resized version of an image and return its pathname.
+
+    Arguments:
+    entry -- the entry for the image to resize
+    filename -- the filename of the original image being resized
+    basename -- simple basename of the given filename
+    file_tail -- ending string and extension for the resized filename
+    exif_tags -- EXIF data for the original image
+    workdir -- directory path for storing converted image files
+    new_size -- 2-tuple size for the resized image
+    size_limits (optional) -- image is only resized if it exceeds this size
+
+    """
+    try:
+        resized = Image.open(filename)
+    except IOError:
+        raise BadMediaFail()
+    resized = exif_fix_image_orientation(resized, exif_tags)  # Fix orientation
+
+    if ((size_limits is None) or
+        (resized.size[0] > size_limits[0]) or
+        (resized.size[1] > size_limits[1])):
+        resized.thumbnail(new_size, Image.ANTIALIAS)
+
+    resized_filename = (basename[:MAX_FILENAME_LENGTH - len(file_tail)] +
+                        file_tail)
+    resized_filepath = create_pub_filepath(entry, resized_filename)
+
+    # Copy the new file to the conversion subdir, then remotely.
+    tmp_resized_filename = os.path.join(workdir, resized_filename)
+    with file(tmp_resized_filename, 'w') as resized_file:
+        resized.save(resized_file)
+    mgg.public_store.copy_local_to_storage(
+        tmp_resized_filename, resized_filepath)
+    return resized_filepath
+
 def process_image(entry):
     """
     Code to process an image
@@ -46,50 +86,17 @@ def process_image(entry):
     exif_tags = extract_exif(queued_filename)
     gps_data = get_gps_data(exif_tags)
 
-    try:
-        thumb = Image.open(queued_filename)
-    except IOError:
-        raise BadMediaFail()
-
-    thumb = exif_fix_image_orientation(thumb, exif_tags)
-
-    thumb.thumbnail(THUMB_SIZE, Image.ANTIALIAS)
-
-    # Copy the thumb to the conversion subdir, then remotely.
-    thumb_filename = 'thumbnail' + extension
-    thumb_filepath = create_pub_filepath(entry, thumb_filename)
-
-    tmp_thumb_filename = os.path.join(
-        conversions_subdir, thumb_filename)
-
-    with file(tmp_thumb_filename, 'w') as thumb_file:
-        thumb.save(thumb_file)
-
-    mgg.public_store.copy_local_to_storage(
-        tmp_thumb_filename, thumb_filepath)
+    # Always create a small thumbnail
+    thumb_filepath = resize_image(entry, queued_filename, basename,
+                                  '.thumbnail' + extension, exif_tags,
+                                  conversions_subdir, THUMB_SIZE)
 
     # If the size of the original file exceeds the specified size of a `medium`
-    # file, a `medium.jpg` files is created and later associated with the media
+    # file, a `.medium.jpg` files is created and later associated with the media
     # entry.
-    medium = Image.open(queued_filename)
-
-    # Fix orientation
-    medium = exif_fix_image_orientation(medium, exif_tags)
-
-    if medium.size[0] > MEDIUM_SIZE[0] or medium.size[1] > MEDIUM_SIZE[1]:
-        medium.thumbnail(MEDIUM_SIZE, Image.ANTIALIAS)
-
-    medium_filename = 'medium' + extension
-    medium_filepath = create_pub_filepath(entry, medium_filename)
-
-    tmp_medium_filename = os.path.join(
-        conversions_subdir, medium_filename)
-
-    with file(tmp_medium_filename, 'w') as medium_file:
-        medium.save(medium_file)
-
-    mgg.public_store.copy_local_to_storage(
-        tmp_medium_filename, medium_filepath)
+    medium_filepath = resize_image(entry, queued_filename, basename,
+                                   '.medium' + extension, exif_tags,
+                                   conversions_subdir, MEDIUM_SIZE, MEDIUM_SIZE)
 
     # we have to re-read because unlike PIL, not everything reads
     # things in string representation :)
@@ -115,10 +122,13 @@ def process_image(entry):
 
     # Insert exif data into database
     media_data = entry.setdefault('media_data', {})
-    media_data['exif'] = {
-        'clean': clean_exif(exif_tags)}
-    media_data['exif']['useful'] = get_useful(
-        media_data['exif']['clean'])
+
+    # TODO: Fix for sql media_data, when exif is in sql
+    if media_data is not None:
+        media_data['exif'] = {
+            'clean': clean_exif(exif_tags)}
+        media_data['exif']['useful'] = get_useful(
+            media_data['exif']['clean'])
 
     if len(gps_data):
         for key in list(gps_data.keys()):