server: Add XSNWorkQueueDepthExceeded error

Now, when the XSN RPC API returns the "Work Queue Depth Exceeded" error,
it will be mapped to the XSNWorkQueueDepthExceeded error.

server/app/com/xsn/explorer/errors/xsnErrors.scala

@@ -24,3 +24,11 @@ case object XSNUnexpectedResponseError extends XSNServerError {
     List(error)
   }
 }
+
+case object XSNWorkQueueDepthExceeded extends XSNServerError {
+  override def toPublicErrorList(messagesApi: MessagesApi)(implicit lang: Lang): List[PublicError] = {
+    val message = messagesApi("xsn.server.unexpectedError")
+    val error = GenericPublicError(message)
+    List(error)
+  }
+}

server/app/com/xsn/explorer/services/XSNService.scala

@@ -402,7 +402,7 @@ class XSNServiceRPCImpl @Inject() (
         .asOpt[JsValue]
         .filter(_ != JsNull)
 
-    jsonErrorMaybe
+    val errorMaybe = jsonErrorMaybe
         .flatMap { jsonError =>
           // from error code if possible
           (jsonError \ "code")
@@ -416,6 +416,12 @@ class XSNServiceRPCImpl @Inject() (
                     .map(XSNMessageError.apply)
               }
         }
+
+    errorMaybe
+        .collect {
+          case XSNMessageError("Work queue depth exceeded") => XSNWorkQueueDepthExceeded
+        }
+        .orElse(errorMaybe)
   }
 
   private def getResult[A](

server/test/com/xsn/explorer/services/XSNServiceRPCImplSpec.scala

@@ -163,6 +163,19 @@ class XSNServiceRPCImplSpec extends WordSpec with MustMatchers with ScalaFutures
         result mustEqual Bad(XSNUnexpectedResponseError).accumulating
       }
     }
+
+    "handle work queue depth exceeded" in {
+      val txid = createTransactionId("0834641a7d30d8a2d2b451617599670445ee94ed7736e146c13be260c576c641")
+
+      val responseBody = createRPCErrorResponse(-1, "Work queue depth exceeded")
+      val json = Json.parse(responseBody)
+
+      mockRequest(request, response)(200, json)
+
+      whenReady(service.getTransaction(txid)) { result =>
+        result mustEqual Bad(XSNWorkQueueDepthExceeded).accumulating
+      }
+    }
   }
 
   "getRawTransaction" should {