persistent rabbitmq queue for status (#216)

Create a persistent unique id for clowder instance and use that for the RabbitMQ status queue.

Author: robkooper

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
   folders and technical metadata. Downloading datasets now includes extra Datacite and Clowder metadata.
 - Endpoint /api/files/bulkRemove to delete multiple files in one call. [#12](https://github.com/clowder-framework/clowder/issues/12)
 - Log an event each time that a user archives or unarchives a file.
+- Clowder will use the same queue for responses, preventing status messages from getting lost.
 
 ### Changed
 - Updated Sphinx dependencies due to security and changes in required packages.

app/Global.scala

@@ -45,6 +45,9 @@ object Global extends WithFilters(new GzipFilter(), new Jsonp(), CORSFilter()) w
 
     val users: UserService = DI.injector.getInstance(classOf[UserService])
 
+    // get clowder unique ID
+    Logger.info(s"Starting clowder with id = ${AppConfiguration.getInstance}")
+
     // set the default ToS version
     AppConfiguration.setDefaultTermsOfServicesVersion()
 

app/api/Status.scala

@@ -31,7 +31,8 @@ class Status @Inject()(spaces: SpaceService,
 
   def status = UserAction(needActive=false) { implicit request =>
 
-    Ok(Json.obj("version" -> getVersionInfo,
+    Ok(Json.obj("instance" -> AppConfiguration.getInstance,
+      "version" -> getVersionInfo,
       "counts" -> getCounts(request.user),
       "plugins" -> getPlugins(request.user),
       "extractors" -> Json.toJson(extractors.getExtractorNames(List.empty))))

app/services/AppConfigurationService.scala

@@ -70,6 +70,18 @@ trait AppConfigurationService {
 object AppConfiguration {
   val appConfig: AppConfigurationService = DI.injector.getInstance(classOf[AppConfigurationService])
 
+  // ----------------------------------------------------------------------
+  def getInstance: String = {
+    appConfig.getProperty[String]("instance") match {
+      case Some(id) => id
+      case None => {
+        val id = scala.util.Random.alphanumeric.take(10).mkString
+        appConfig.setProperty("instance", id)
+        id
+      }
+    }
+  }
+
   // ----------------------------------------------------------------------
 
   /** Set the default theme */

app/services/rabbitmq/RabbitMQMessageService.scala

@@ -100,8 +100,9 @@ class RabbitMQMessageService extends MessageService {
       }
 
       // create an anonymous queue for replies
-      val replyQueueName = channel.get.queueDeclare().getQueue
-      Logger.debug("Reply queue name: " + replyQueueName)
+      val replyQueueName = s"clowder.${AppConfiguration.getInstance}"
+      channel.get.queueDeclare(replyQueueName, true, false, false, null)
+      Logger.info("Reply queue name: " + replyQueueName)
 
       // get bindings stored in broker
       val queueBindingsFuture = getQueuesNamesForAnExchange(exchange)