Support short custom YouTube channel URLs

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/linkHandler/YoutubeChannelLinkHandlerFactory.java

@@ -1,5 +1,6 @@
 package org.schabi.newpipe.extractor.services.youtube.linkHandler;
 
+import java.util.regex.Pattern;
 import org.schabi.newpipe.extractor.exceptions.ParsingException;
 import org.schabi.newpipe.extractor.linkhandler.ListLinkHandlerFactory;
 import org.schabi.newpipe.extractor.services.youtube.YoutubeParsingHelper;
@@ -32,6 +33,9 @@ public class YoutubeChannelLinkHandlerFactory extends ListLinkHandlerFactory {
 
     private static final YoutubeChannelLinkHandlerFactory instance = new YoutubeChannelLinkHandlerFactory();
 
+    private static final Pattern excludedSegments =
+      Pattern.compile("playlist|watch|attribution_link|watch_popup|embed|feed|select_site");
+
     public static YoutubeChannelLinkHandlerFactory getInstance() {
         return instance;
     }
@@ -48,27 +52,44 @@ public static YoutubeChannelLinkHandlerFactory getInstance() {
     public String getUrl(String id, List<String> contentFilters, String searchFilter) {
         return "https://www.youtube.com/" + id;
     }
+
+    /**
+     * Returns true if path conform to
+     * custom short channel URLs like youtube.com/yourcustomname
+     *
+     * @param splitPath path segments array
+     * @return true - if value conform to short channel URL, false - not
+     */
+    private boolean isCustomShortChannelUrl(final String[] splitPath) {
+        return splitPath.length == 1 && !excludedSegments.matcher(splitPath[0]).matches();
+    }
 
     @Override
     public String getId(String url) throws ParsingException {
         try {
-            URL urlObj = Utils.stringToURL(url);
+            final URL urlObj = Utils.stringToURL(url);
             String path = urlObj.getPath();
 
             if (!Utils.isHTTP(urlObj) || !(YoutubeParsingHelper.isYoutubeURL(urlObj) ||
                     YoutubeParsingHelper.isInvidioURL(urlObj) || YoutubeParsingHelper.isHooktubeURL(urlObj))) {
                 throw new ParsingException("the URL given is not a Youtube-URL");
             }
 
-            if (!path.startsWith("/user/") && !path.startsWith("/channel/") && !path.startsWith("/c/")) {
-                throw new ParsingException("the URL given is neither a channel nor an user");
-            }
-
             // remove leading "/"
             path = path.substring(1);
-
             String[] splitPath = path.split("/");
-            String id = splitPath[1];
+
+            // Handle custom short channel URLs like youtube.com/yourcustomname
+            if (isCustomShortChannelUrl(splitPath)) {
+                path = "c/" + path;
+                splitPath = path.split("/");
+            }
+
+            if (!path.startsWith("user/") && !path.startsWith("channel/") && !path.startsWith("c/")) {
+                throw new ParsingException("the URL given is neither a channel nor an user");
+            }
+
+            final String id = splitPath[1];
 
             if (id == null || !id.matches("[A-Za-z0-9_-]+")) {
                 throw new ParsingException("The given id is not a Youtube-Video-ID");

extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/YoutubeChannelLinkHandlerFactoryTest.java

@@ -8,6 +8,7 @@
 import org.schabi.newpipe.extractor.services.youtube.linkHandler.YoutubeChannelLinkHandlerFactory;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -30,6 +31,8 @@ public void acceptUrlTest() throws ParsingException {
 
         assertTrue(linkHandler.acceptUrl("https://www.youtube.com/c/creatoracademy"));
 
+        assertTrue(linkHandler.acceptUrl("https://youtube.com/DIMENSI0N"));
+
         assertTrue(linkHandler.acceptUrl("https://www.youtube.com/channel/UClq42foiSgl7sSpLupnugGA"));
         assertTrue(linkHandler.acceptUrl("https://www.youtube.com/channel/UClq42foiSgl7sSpLupnugGA/videos?disable_polymer=1"));
 
@@ -44,6 +47,18 @@ public void acceptUrlTest() throws ParsingException {
 
         assertTrue(linkHandler.acceptUrl("https://invidio.us/channel/UClq42foiSgl7sSpLupnugGA"));
         assertTrue(linkHandler.acceptUrl("https://invidio.us/channel/UClq42foiSgl7sSpLupnugGA/videos?disable_polymer=1"));
+        assertTrue(linkHandler.acceptUrl("https://www.youtube.com/watchismo"));
+
+
+        // do not accept URLs which are not channels
+        assertFalse(linkHandler.acceptUrl("https://www.youtube.com/watch?v=jZViOEv90dI&t=100"));
+        assertFalse(linkHandler.acceptUrl("http://www.youtube.com/watch_popup?v=uEJuoEs1UxY"));
+        assertFalse(linkHandler.acceptUrl("http://www.youtube.com/attribution_link?a=JdfC0C9V6ZI&u=%2Fwatch%3Fv%3DEhxJLojIE_o%26feature%3Dshare"));
+        assertFalse(linkHandler.acceptUrl("https://www.youtube.com/playlist?list=PLW5y1tjAOzI3orQNF1yGGVL5x-pR2K1d"));
+        assertFalse(linkHandler.acceptUrl("https://www.youtube.com/embed/jZViOEv90dI"));
+        assertFalse(linkHandler.acceptUrl("https://www.youtube.com/feed/subscriptions?list=PLz8YL4HVC87WJQDzVoY943URKQCsHS9XV"));
+        assertFalse(linkHandler.acceptUrl("https://www.youtube.com/?app=desktop&persist_app=1"));
+        assertFalse(linkHandler.acceptUrl("https://m.youtube.com/select_site"));
     }
 
     @Test