Fixed: Ping plex.tv to keep auth token active

Closes #2981

(cherry picked from commit 93bd8543b158c952b50e56d4339e4a3c699770b0)

src/NzbDrone.Core/Notifications/Plex/PlexTv/PlexTvProxy.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Net;
 using NLog;
 using NzbDrone.Common.EnvironmentInfo;
@@ -10,6 +11,7 @@ namespace NzbDrone.Core.Notifications.Plex.PlexTv
     public interface IPlexTvProxy
     {
         string GetAuthToken(string clientIdentifier, int pinId);
+        bool Ping(string clientIdentifier, string authToken);
     }
 
     public class PlexTvProxy : IPlexTvProxy
@@ -38,6 +40,29 @@ namespace NzbDrone.Core.Notifications.Plex.PlexTv
             return response.AuthToken;
         }
 
+        public bool Ping(string clientIdentifier, string authToken)
+        {
+            try
+            {
+                // Allows us to tell plex.tv that we're still active and tokens should not be expired.
+                var request = BuildRequest(clientIdentifier);
+
+                request.ResourceUrl = "/api/v2/ping";
+                request.AddQueryParam("X-Plex-Token", authToken);
+
+                ProcessRequest(request);
+
+                return true;
+            }
+            catch (Exception e)
+            {
+                // Catch all exceptions and log at trace, this information could be interesting in debugging, but expired tokens will be handled elsewhere.
+                _logger.Trace(e, "Unable to ping plex.tv");
+            }
+
+            return false;
+        }
+
         private HttpRequestBuilder BuildRequest(string clientIdentifier)
         {
             var requestBuilder = new HttpRequestBuilder("https://plex.tv")

src/NzbDrone.Core/Notifications/Plex/PlexTv/PlexTvService.cs

@@ -1,6 +1,8 @@
+using System;
 using System.Linq;
 using System.Net.Http;
 using System.Text;
+using NzbDrone.Common.Cache;
 using NzbDrone.Common.EnvironmentInfo;
 using NzbDrone.Common.Http;
 using NzbDrone.Core.Configuration;
@@ -12,17 +14,20 @@ namespace NzbDrone.Core.Notifications.Plex.PlexTv
         PlexTvPinUrlResponse GetPinUrl();
         PlexTvSignInUrlResponse GetSignInUrl(string callbackUrl, int pinId, string pinCode);
         string GetAuthToken(int pinId);
+        void Ping(string authToken);
     }
 
     public class PlexTvService : IPlexTvService
     {
         private readonly IPlexTvProxy _proxy;
         private readonly IConfigService _configService;
+        private readonly ICached<bool> _cache;
 
-        public PlexTvService(IPlexTvProxy proxy, IConfigService configService)
+        public PlexTvService(IPlexTvProxy proxy, IConfigService configService, ICacheManager cacheManager)
         {
             _proxy = proxy;
             _configService = configService;
+            _cache = cacheManager.GetCache<bool>(GetType());
         }
 
         public PlexTvPinUrlResponse GetPinUrl()
@@ -81,5 +86,11 @@ namespace NzbDrone.Core.Notifications.Plex.PlexTv
 
             return authToken;
         }
+
+        public void Ping(string authToken)
+        {
+            // Ping plex.tv if we haven't done so in the last 24 hours for this auth token.
+            _cache.Get(authToken, () => _proxy.Ping(_configService.PlexClientIdentifier, authToken), TimeSpan.FromHours(24));
+        }
     }
 }

src/NzbDrone.Core/Notifications/Plex/Server/PlexServer.cs

@@ -55,6 +55,8 @@ namespace NzbDrone.Core.Notifications.Plex.Server
 
         private void UpdateIfEnabled(Artist artist)
         {
+            _plexTvService.Ping(Settings.AuthToken);
+
             if (Settings.UpdateLibrary)
             {
                 _logger.Debug("Scheduling library update for artist {0} {1}", artist.Id, artist.Name);
@@ -68,7 +70,8 @@ namespace NzbDrone.Core.Notifications.Plex.Server
 
         public override void ProcessQueue()
         {
-            PlexUpdateQueue queue = _pendingArtistCache.Find(Settings.Host);
+            var queue = _pendingArtistCache.Find(Settings.Host);
+
             if (queue == null)
             {
                 return;
@@ -121,6 +124,8 @@ namespace NzbDrone.Core.Notifications.Plex.Server
 
         public override ValidationResult Test()
         {
+            _plexTvService.Ping(Settings.AuthToken);
+
             var failures = new List<ValidationFailure>();
 
             failures.AddIfNotNull(_plexServerService.Test(Settings));