improve torznab error handling

src/Jackett/Controllers/ResultsController.cs

@@ -34,7 +34,7 @@ namespace Jackett.Controllers
                 return;
 #endif
             if (queryApiKey != validApiKey)
-                actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.Unauthorized);
+                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.Unauthorized, 100, $"Invalid API Key");
         }
     }
 
@@ -53,7 +53,7 @@ namespace Jackett.Controllers
             if (!parameters.ContainsKey("indexerId"))
             {
                 indexerController.CurrentIndexer = null;
-                actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.Unauthorized, "Invalid parameter");
+                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 200, $"indexer is not specified");
                 return;
             }
 
@@ -61,7 +61,7 @@ namespace Jackett.Controllers
             if (indexerId.IsNullOrEmptyOrWhitespace())
             {
                 indexerController.CurrentIndexer = null;
-                actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.Unauthorized, "Invalid parameter");
+                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 201, $"Indexer is not specified (empty value)");
                 return;
             }
 
@@ -71,14 +71,14 @@ namespace Jackett.Controllers
             if (indexer == null)
             {
                 indexerController.CurrentIndexer = null;
-                actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.Unauthorized, "Invalid parameter");
+                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 201, $"Indexer is not supported");
                 return;
             }
 
             if (!indexer.IsConfigured)
             {
                 indexerController.CurrentIndexer = null;
-                actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.Unauthorized, "Indexer is not configured");
+                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 201, $"Indexer is not configured");
                 return;
             }
 
@@ -104,7 +104,7 @@ namespace Jackett.Controllers
             var queryType = query.GetType();
             var converter = queryType.GetMethod("ToTorznabQuery", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.Public);
             if (converter == null)
-                actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.BadRequest, "");
+                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.BadRequest, 900, $"ToTorznabQuery() not found");
             var converted = converter.Invoke(null, new object[] { query });
             var torznabQuery = converted as TorznabQuery;
             resultController.CurrentQuery = torznabQuery;
@@ -113,7 +113,7 @@ namespace Jackett.Controllers
                 return;
 
             if (!resultController.CurrentIndexer.CanHandleQuery(resultController.CurrentQuery))
-                actionContext.Response = actionContext.Request.CreateErrorResponse(HttpStatusCode.BadRequest, $"{resultController.CurrentIndexer.ID} does not support the requested query. Please check the capabilities (t=caps) and make sure the search mode and categories are supported.");
+                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotImplemented, 201, $"{resultController.CurrentIndexer.ID} does not support the requested query. Please check the capabilities (t=caps) and make sure the search mode and categories are supported.");
         }
     }
 
@@ -309,6 +309,8 @@ namespace Jackett.Controllers
                 }
             }
 
+            try
+            {
                 var result = await CurrentIndexer.ResultsForQuery(CurrentQuery);
 
                 // Some trackers do not support multiple category filtering so filter the releases that match manually.
@@ -366,8 +368,29 @@ namespace Jackett.Controllers
                     Content = new StringContent(xml, Encoding.UTF8, "application/rss+xml")
                 });
             }
+            catch (Exception e)
+            {
+                Engine.Logger.Error(e);
+                return GetErrorXML(900, e.Message);
+            }
+        }
 
-        public IHttpActionResult GetErrorXML(int code, string description)
+        static public HttpResponseMessage GetErrorHttpResponseMessage(HttpActionContext actionContext, HttpStatusCode status, int torznabCode, string description)
+        {
+            var parameters = actionContext.RequestContext.RouteData.Values;
+            var action = parameters["action"] as string;
+
+            if (action == "torznab")
+            {
+                return GetErrorXMLHttpResponseMessage(torznabCode, description);
+            }
+            else
+            {
+                return actionContext.Request.CreateErrorResponse(status, description);
+            }
+        }
+
+        static public HttpResponseMessage GetErrorXMLHttpResponseMessage(int code, string description)
         {
             var xdoc = new XDocument(
                 new XDeclaration("1.0", "UTF-8", null),
@@ -379,10 +402,15 @@ namespace Jackett.Controllers
 
             var xml = xdoc.Declaration.ToString() + Environment.NewLine + xdoc.ToString();
 
-            return ResponseMessage(new HttpResponseMessage()
+            return new HttpResponseMessage()
             {
                 Content = new StringContent(xml, Encoding.UTF8, "application/xml")
-            });
+            };
+        }
+
+        public IHttpActionResult GetErrorXML(int code, string description)
+        {
+            return ResponseMessage(GetErrorXMLHttpResponseMessage(code, description));
         }
 
         [HttpGet]