X-Git-Url: https://git.mdrn.pl/librarian.git/blobdiff_plain/e93c90799341b6627eca7fe03c7fefb95b4db9eb..43eba2bf6d9822eff219c4bdc78b715eecfe2fe1:/librarian/formats/cover/evens/__init__.py

diff --git a/librarian/formats/cover/evens/__init__.py b/librarian/formats/cover/evens/__init__.py
index e07f78b..bc05ec4 100644
--- a/librarian/formats/cover/evens/__init__.py
+++ b/librarian/formats/cover/evens/__init__.py
@@ -27,6 +27,9 @@ class EvensCover(Cover):
             raise BuildError('No cover specified (metadata field relation.coverimage.url empty)')
         if cover_url.startswith('file://'):
             cover_url = ctx.files_path + urllib.quote(cover_url[7:])
+        IMG_EXT = ('png', 'jpg', 'jpeg', 'gif')
+        if '.' not in cover_url or cover_url.rsplit('.')[1].lower() not in IMG_EXT:
+            raise BuildError('Wrong cover format, should be PNG, JPG or GIF')
         try:
             self.background_img = urlopen(cover_url)
         except URLError: