File load-tags-from-stream-as-metadata.patch of Package rygel-test

Listen for tag events and add some to meta-data
--- src/librygel-renderer-gst/rygel-playbin-player.vala	Fri Jul 21 18:58:26 2017
+++ src/librygel-renderer-gst/rygel-playbin-player.vala	Thu Oct 12 11:42:35 2017
@@ -510,6 +510,108 @@
                structure.get_name () == "image/png";
     }
 
+    // copied from rygel-player-controller.vala
+    /*protected string xml_escape (string input) {
+        var result = input.replace ("\"", "&quot;");
+        result = result.replace ("<", "&lt;");
+        result = result.replace (">", "&gt;");
+        result = result.replace ("'", "&apos;");
+        result = result.replace ("&", "&amp;");
+
+        return result;
+    }*/
+
+    // copied from rygel-player-default-controller.vala
+    private const string DIDL_FRAME_TEMPLATE = "<DIDL-Lite " +
+        "xmlns:dc=\"http://purl.org/dc/elements/1.1/\" " +
+        "xmlns:upnp=\"urn:schemas-upnp-org:metadata-1-0/upnp/\" " +
+        "xmlns:dlna=\"urn:schemas-dlna-org:metadata-1-0/\" " +
+        "xmlns=\"urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/\">" +
+        "%s</DIDL-Lite>";
+
+    private void modify_didl_for_new_tag (string title, string artist) {
+        DIDLLiteObject didl_object = null;
+        var didl_parser = new DIDLLiteParser ();
+        string class;
+
+        if((title == null || title.length == 0)
+           && (artist == null || artist.length == 0))
+            return;
+
+        didl_parser.object_available.connect ((object) => {
+            didl_object = object;
+        });
+
+        try {
+            didl_parser.parse_didl (this.metadata);
+        } catch (Error parse_err) {
+             return;
+        }
+
+        if (didl_object == null) 
+          return;
+
+        // only modify for internet radio stations
+        class = didl_object.get_upnp_class();
+        if(class == null || class != "object.item.audioItem.audioBroadcast")
+            return;
+
+        if(title != null && title.length > 0)
+          didl_object.title = title;
+        if(artist != null && artist.length > 0)
+          didl_object.artist = artist;
+
+        //debug ("modify_didl_for_new_tag before: %s\n", this.metadata);
+        this.metadata = DIDL_FRAME_TEMPLATE.printf(didl_object.get_xml_string());
+        //debug ("modify_didl_for_new_tag after: %s\n", this.metadata);
+    }
+
+    private void handle_tags (Gst.TagList tag_list) {
+        int i,j,n;
+        string tag;
+        string value = "";
+        string title = "";
+        string artist = "";
+        uint size, uintv;
+
+        n = tag_list.n_tags();
+        for(i=0;i<n;i++) {
+          tag = tag_list.nth_tag_name(i);
+          /*size = tag_list.get_tag_size(tag);
+          debug ("tag[%d]=%s of size %u\n", i, tag, size);
+          for(j=0;j<size;j++) {
+            if(tag_list.get_string_index (tag, j, out value))
+              debug ("  value[%d]=%s\n", j, value);
+            else if(tag_list.get_uint_index (tag, j, out uintv))
+              debug ("  value[%d]=%u\n", j, uintv);
+          }*/
+          switch (tag) {
+            case "title":
+            case "organization":
+            case "genre":
+            case "audio-codec":
+              tag_list.get_string(tag, out value);
+              debug ("tag: %s = %s\n", tag, value);
+              break;
+            case "nominal-bitrate":
+              tag_list.get_uint(tag, out uintv);
+              debug ("tag: %s = %u\n", tag, uintv);
+              break;
+            default:
+              break;
+          }
+          switch (tag) {
+            case "title":
+              title = value;
+              break;
+            case "organization":
+              artist = value;
+              break;
+          }
+        }
+        modify_didl_for_new_tag(title, artist);
+    }
+
     private void bus_handler (Gst.Bus bus,
                               Message message) {
         switch (message.type) {
@@ -562,6 +664,11 @@
                     this.playback_state = "PLAYING";
                 }
             }
+            break;
+        case MessageType.TAG:
+            Gst.TagList tag_list;
+            message.parse_tag (out tag_list);
+            handle_tags(tag_list);
             break;
         case MessageType.EOS:
             if (!this.is_rendering_image ()) {