YARN-8368. yarn app start cli should print applicationId. Contributed by Rohith Sharma K S

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-services/hadoop-yarn-services-api/src/main/java/org/apache/hadoop/yarn/service/webapp/ApiServer.java

@@ -641,20 +641,24 @@ public class ApiServer {
   private Response startService(String appName,
       final UserGroupInformation ugi) throws IOException,
       InterruptedException {
-    ugi.doAs(new PrivilegedExceptionAction<Void>() {
-      @Override
-      public Void run() throws YarnException, IOException {
+    ApplicationId appId =
+        ugi.doAs(new PrivilegedExceptionAction<ApplicationId>() {
+          @Override public ApplicationId run()
+              throws YarnException, IOException {
             ServiceClient sc = getServiceClient();
             sc.init(YARN_CONFIG);
             sc.start();
             sc.actionStart(appName);
+            ApplicationId appId = sc.getAppId(appName);
             sc.close();
-        return null;
+            return appId;
           }
         });
     LOG.info("Successfully started service " + appName);
     ServiceStatus status = new ServiceStatus();
-    status.setDiagnostics("Service " + appName + " is successfully started.");
+    status.setDiagnostics(
+        "Service " + appName + " is successfully started with ApplicationId: "
+            + appId);
     status.setState(ServiceState.ACCEPTED);
     return formatResponse(Status.OK, status);
   }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-services/hadoop-yarn-services-api/src/test/java/org/apache/hadoop/yarn/service/ServiceClientTest.java

@@ -34,8 +34,10 @@ import org.apache.hadoop.yarn.service.utils.SliderFileSystem;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
 
@@ -50,6 +52,8 @@ public class ServiceClientTest extends ServiceClient {
   private Service goodServiceStatus = buildLiveGoodService();
   private boolean initialized;
   private Set<String> expectedInstances = new HashSet<>();
+  private Map<String, ApplicationId> serviceAppId = new HashMap<>();
+
 
   public ServiceClientTest() {
     super();
@@ -83,7 +87,10 @@ public class ServiceClientTest extends ServiceClient {
   public ApplicationId actionCreate(Service service) throws IOException {
     ServiceApiUtil.validateAndResolveService(service,
         new SliderFileSystem(conf), getConfig());
-    return ApplicationId.newInstance(System.currentTimeMillis(), 1);
+    ApplicationId appId =
+        ApplicationId.newInstance(System.currentTimeMillis(), 1);
+    serviceAppId.put(service.getName(), appId);
+    return appId;
   }
 
   @Override
@@ -99,6 +106,9 @@ public class ServiceClientTest extends ServiceClient {
   public int actionStart(String serviceName)
       throws YarnException, IOException {
     if (serviceName != null && serviceName.equals("jenkins")) {
+      ApplicationId appId =
+          ApplicationId.newInstance(System.currentTimeMillis(), 1);
+      serviceAppId.put(serviceName, appId);
       return EXIT_SUCCESS;
     } else {
       throw new ApplicationNotFoundException("");
@@ -207,4 +217,10 @@ public class ServiceClientTest extends ServiceClient {
     comp.setContainers(containers);
     return service;
   }
+
+  @Override
+  public synchronized ApplicationId getAppId(String serviceName)
+      throws IOException, YarnException {
+    return serviceAppId.get(serviceName);
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-services/hadoop-yarn-services-core/src/main/java/org/apache/hadoop/yarn/service/client/ServiceClient.java

@@ -978,6 +978,8 @@ public class ServiceClient extends AppAdminClient implements SliderExitCodes,
       // see if it is actually running and bail out;
       verifyNoLiveAppInRM(serviceName, "start");
       ApplicationId appId = submitApp(service);
+      cachedAppInfo.put(serviceName, new AppInfo(appId, service
+          .getKerberosPrincipal().getPrincipalName()));
       service.setId(appId.toString());
       // write app definition on to hdfs
       Path appJson = ServiceApiUtil.writeAppDefinition(fs, appDir, service);