[redgifs] add image extractor (#724)

docs/supportedsites.rst

@@ -105,6 +105,7 @@ Read Comic Online    https://readcomiconline.to/         Comic Issues, Comics
 Realbooru            https://realbooru.com/              Pools, Posts, Tag Searches
 RebeccaBlackTech     https://rbt.asia/                   Threads
 Reddit               https://www.reddit.com/             |reddit-C|                                         Optional (OAuth)
+RedGIFs              https://redgifs.com/                individual Images
 rule #34             https://rule34.paheal.net/          Posts, Tag Searches
 Rule 34              https://rule34.xxx/                 Pools, Posts, Tag Searches
 Safebooru            https://safebooru.org/              Pools, Posts, Tag Searches

gallery_dl/extractor/__init__.py

@@ -94,6 +94,7 @@ modules = [
     "readcomiconline",
     "realbooru",
     "reddit",
+    "redgifs",
     "rule34",
     "safebooru",
     "sankaku",

gallery_dl/extractor/redgifs.py

@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+
+# Copyright 2020 Mike Fährmann
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+
+"""Extractors for https://redgifs.com/"""
+
+from .gfycat import GfycatImageExtractor
+
+
+class RedgifsImageExtractor(GfycatImageExtractor):
+    """Extractor for individual images from redgifs.com"""
+    category = "redgifs"
+    pattern = r"(?:https?://)?redgifs\.com/watch/([A-Za-z]+)"
+    test = ("https://redgifs.com/watch/foolishforkedabyssiniancat", {
+        "pattern": "https://giant.gfycat.com/FoolishForkedAbyssiniancat.mp4",
+        "content": "f6e03f1df9a2ff2a74092f53ee7580d2fb943533",
+    })

scripts/supportedsites.py

@@ -68,6 +68,7 @@ CATEGORY_MAP = {
     "powermanga"     : "PowerManga",
     "readcomiconline": "Read Comic Online",
     "rbt"            : "RebeccaBlackTech",
+    "redgifs"        : "RedGIFs",
     "rule34"         : "Rule 34",
     "sankaku"        : "Sankaku Channel",
     "sankakucomplex" : "Sankaku Complex",