[gfycat] Support embeds (#2229)

Closes #2214
Authored by: coletdjnz

yt_dlp/extractor/gfycat.py

@@ -1,6 +1,8 @@
 # coding: utf-8
 from __future__ import unicode_literals
 
+import re
+
 from .common import InfoExtractor
 from ..utils import (
     int_or_none,
@@ -11,7 +13,7 @@ from ..utils import (
 
 
 class GfycatIE(InfoExtractor):
-    _VALID_URL = r'https?://(?:(?:www|giant|thumbs)\.)?gfycat\.com/(?:ru/|ifr/|gifs/detail/)?(?P<id>[^-/?#\.]+)'
+    _VALID_URL = r'(?i)https?://(?:(?:www|giant|thumbs)\.)?gfycat\.com/(?:ru/|ifr/|gifs/detail/)?(?P<id>[^-/?#\."\']+)'
     _TESTS = [{
         'url': 'http://gfycat.com/DeadlyDecisiveGermanpinscher',
         'info_dict': {
@@ -78,8 +80,19 @@ class GfycatIE(InfoExtractor):
     }, {
         'url': 'https://giant.gfycat.com/acceptablehappygoluckyharborporpoise.mp4',
         'only_matching': True
+    }, {
+        'url': 'http://gfycat.com/IFR/JauntyTimelyAmazontreeboa',
+        'only_matching': True
     }]
 
+    @staticmethod
+    def _extract_urls(webpage):
+        return [
+            mobj.group('url')
+            for mobj in re.finditer(
+                r'<(?:iframe|source)[^>]+\bsrc=["\'](?P<url>%s)' % GfycatIE._VALID_URL,
+                webpage)]
+
     def _real_extract(self, url):
         video_id = self._match_id(url)