[gelbooru_v01] replace 'extract_all()' with 'extract_from()'

It's even slightly faster, especially on Python before 3.11

gallery_dl/extractor/gelbooru_v01.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-# Copyright 2021-2022 Mike Fährmann
+# Copyright 2021-2023 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
@@ -19,24 +19,23 @@ class GelbooruV01Extractor(booru.BooruExtractor):
     def _parse_post(self, post_id):
         url = "{}/index.php?page=post&s=view&id={}".format(
             self.root, post_id)
-        page = self.request(url).text
-
-        post = text.extract_all(page, (
-            ("created_at", 'Posted: ', ' <'),
-            ("uploader"  , 'By: ', ' <'),
-            ("width"     , 'Size: ', 'x'),
-            ("height"    , '', ' <'),
-            ("source"    , 'Source: <a href="', '"'),
-            ("rating"    , 'Rating: ', '<'),
-            ("score"     , 'Score: ', ' <'),
-            ("file_url"  , '<img alt="img" src="', '"'),
-            ("tags"      , 'id="tags" name="tags" cols="40" rows="5">', '<'),
-        ))[0]
-
-        post["id"] = post_id
+        extr = text.extract_from(self.request(url).text)
+
+        post = {
+            "id"        : post_id,
+            "created_at": extr('Posted: ', ' <'),
+            "uploader"  : extr('By: ', ' <'),
+            "width"     : extr('Size: ', 'x'),
+            "height"    : extr('', ' <'),
+            "source"    : extr('Source: <a href="', '"'),
+            "rating"    : (extr('Rating: ', '<') or "?")[0].lower(),
+            "score"     : extr('Score: ', ' <'),
+            "file_url"  : extr('<img alt="img" src="', '"'),
+            "tags"      : text.unescape(extr(
+                'id="tags" name="tags" cols="40" rows="5">', '<')),
+        }
+
         post["md5"] = post["file_url"].rpartition("/")[2].partition(".")[0]
-        post["rating"] = (post["rating"] or "?")[0].lower()
-        post["tags"] = text.unescape(post["tags"])
         post["date"] = text.parse_datetime(
             post["created_at"], "%Y-%m-%d %H:%M:%S")
 
@@ -186,7 +185,7 @@ class GelbooruV01PostExtractor(GelbooruV01Extractor):
                 "md5": "2aaa0438d58fc7baa75a53b4a9621bb89a9d3fdb",
                 "rating": "s",
                 "score": str,
-                "source": None,
+                "source": "",
                 "tags": "blush dress green_eyes green_hair hatsune_miku "
                         "long_hair twintails vocaloid",
                 "uploader": "Honochi31",