YARN-9729. [UI2] Fix error message for logs when ATSv2 is offline. Contributed by Zoltan Siegl.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-ui/src/main/webapp/app/controllers/yarn-app/logs.js

@@ -263,5 +263,12 @@ export default Ember.Controller.extend({
   isLogAggregationNotSucceeded: Ember.computed("model.app", function() {
     const logAggregationStatus = this.get("model.app.logAggregationStatus");
     return logAggregationStatus !== "SUCCEEDED";
-  })
+  }),
+
+  isTimelineUnHealthy: function() {
+      if (this.model && this.model.timelineHealth) {
+        return this.model.timelineHealth.get('isTimelineUnHealthy');
+      }
+      return true;
+    }.property('model.timelineHealth')
 });

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-ui/src/main/webapp/app/routes/yarn-app/logs.js

@@ -31,7 +31,10 @@ export default AbstractRoute.extend(AppAttemptMixin, {
       attempts: this.fetchAttemptListFromRMorATS(app_id, this.store).catch(function() {
         return [];
       }),
-      app: this.fetchAppInfoFromRMorATS(app_id, this.store)
+      app: this.fetchAppInfoFromRMorATS(app_id, this.store),
+      timelineHealth: this.store.queryRecord('timeline-health', {}).catch(function() {
+        return null;
+      })
     });
   },
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-ui/src/main/webapp/app/templates/yarn-app/logs.hbs

@@ -32,6 +32,14 @@
             <img src="assets/images/spinner.gif" alt="Loading...">
           </div>
         {{/if}}
+        {{#if isTimelineUnHealthy}}
+          <div class="row">
+            <div class="col-md-8 col-md-offset-2 alert alert-warning text-center">
+              <span class="glyphicon glyphicon-warning-sign" style="padding-right: 10px"></span>
+              <span>Logs are unavailable because Application Timeline Service seems unhealthy.</span>
+            </div>
+          </div>
+        {{else}}
             {{#if attemptList}}
                 <div class="row">
                     <div class="col-md-6">
@@ -70,6 +78,7 @@
                     <h4 class="text-center">No data available!</h4>
                 </div>
             {{/if}}
+        {{/if}}
       </div>
     </div>
   </div>