[gnome-music/wip/jfelder/songeditor-gtk4: 8/32] grltrackerwrapper: Retrieve publication year for songs

[Jean Felder <jfelder src gnome org>]

commit 2114539bc0f7da6c6a7e6f1c748db981d62e8de6
Author: Sumaid Syed <sumaidsyed gmail com>
Date:   Wed Jul 29 12:03:58 2020 +0200

    grltrackerwrapper: Retrieve publication year for songs
    
    Based on the patches by Jean Felder.
    
    https://gitlab.gnome.org/GNOME/gnome-music/issues/293

 gnomemusic/grilowrappers/grltrackerwrapper.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/gnomemusic/grilowrappers/grltrackerwrapper.py b/gnomemusic/grilowrappers/grltrackerwrapper.py
index 111c24c3a..60ce6e4d6 100644
--- a/gnomemusic/grilowrappers/grltrackerwrapper.py
+++ b/gnomemusic/grilowrappers/grltrackerwrapper.py
@@ -427,7 +427,7 @@ class GrlTrackerWrapper(GObject.GObject):
             ?type ?urn ?title ?id ?url
             ?artist ?album
             ?duration ?trackNumber
-            ?albumDiscNumber
+            ?albumDiscNumber ?publicationDate
             nie:usageCounter(?urn) AS ?playCount
             ?tag AS ?favorite
         WHERE {{
@@ -445,8 +445,10 @@ class GrlTrackerWrapper(GObject.GObject):
                         nmm:trackNumber(?song) AS ?trackNumber
                         nmm:setNumber(nmm:musicAlbumDisc(?song))
                             AS ?albumDiscNumber
+                        YEAR(?date) AS ?publicationDate
                     WHERE {{
                         ?song a nmm:MusicPiece .
+                        OPTIONAL {{ ?song nie:contentCreated ?date . }}
                         {songs_filter}
                         {location_filter}
                     }}