YARN-8693. Add signalToContainer REST API for RMWebServices. Contributed by Tao Yang.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMWSConsts.java

@@ -189,6 +189,12 @@ public final class RMWSConsts {
   public static final String CHECK_USER_ACCESS_TO_QUEUE =
       "/queues/{queue}/access";
 
+  /**
+   * Path for {@code RMWebServiceProtocol#signalContainer}.
+   */
+  public static final String SIGNAL_TO_CONTAINER =
+      "/containers/{containerid}/signal/{command}";
+
   // ----------------QueryParams for RMWebServiceProtocol----------------
 
   public static final String TIME = "time";
@@ -229,6 +235,8 @@ public final class RMWSConsts {
   public static final String REQUEST_PRIORITIES = "requestPriorities";
   public static final String ALLOCATION_REQUEST_IDS = "allocationRequestIds";
   public static final String GROUP_BY = "groupBy";
+  public static final String SIGNAL = "signal";
+  public static final String COMMAND = "command";
 
   private RMWSConsts() {
     // not called

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMWebServiceProtocol.java

@@ -712,4 +712,17 @@ public interface RMWebServiceProtocol {
   RMQueueAclInfo checkUserAccessToQueue(String queue, String username,
       String queueAclType, HttpServletRequest hsr)
       throws AuthorizationException;
+
+  /**
+   * This method sends a signal to container.
+   * @param containerId containerId
+   * @param command signal command, it could be OUTPUT_THREAD_DUMP/
+   *                GRACEFUL_SHUTDOWN/FORCEFUL_SHUTDOWN
+   * @param req request
+   * @return Response containing the status code
+   * @throws AuthorizationException if the user is not authorized to invoke this
+   *                                method.
+   */
+  Response signalToContainer(String containerId, String command,
+      HttpServletRequest req) throws AuthorizationException;
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMWebServices.java

@@ -94,6 +94,7 @@ import org.apache.hadoop.yarn.api.protocolrecords.ReservationListResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.ReservationSubmissionRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.ReservationSubmissionResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.ReservationUpdateRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SignalContainerRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.SubmitApplicationRequest;
 import org.apache.hadoop.yarn.api.protocolrecords.SubmitApplicationResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.UpdateApplicationPriorityRequest;
@@ -104,6 +105,7 @@ import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.api.records.ApplicationReport;
 import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;
 import org.apache.hadoop.yarn.api.records.ApplicationTimeoutType;
+import org.apache.hadoop.yarn.api.records.ContainerId;
 import org.apache.hadoop.yarn.api.records.ContainerReport;
 import org.apache.hadoop.yarn.api.records.FinalApplicationStatus;
 import org.apache.hadoop.yarn.api.records.NodeId;
@@ -118,6 +120,7 @@ import org.apache.hadoop.yarn.api.records.ReservationRequestInterpreter;
 import org.apache.hadoop.yarn.api.records.ReservationRequests;
 import org.apache.hadoop.yarn.api.records.Resource;
 import org.apache.hadoop.yarn.api.records.ResourceOption;
+import org.apache.hadoop.yarn.api.records.SignalContainerCommand;
 import org.apache.hadoop.yarn.api.records.YarnApplicationState;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.exceptions.YarnException;
@@ -2550,4 +2553,35 @@ public class RMWebServices extends WebServices implements RMWebServiceProtocol {
 
     return new RMQueueAclInfo(true, user.getUserName(), "");
   }
+
+  @POST
+  @Path(RMWSConsts.SIGNAL_TO_CONTAINER)
+  @Produces({ MediaType.APPLICATION_JSON + "; " + JettyUtils.UTF_8,
+      MediaType.APPLICATION_XML + "; " + JettyUtils.UTF_8 })
+  @Override
+  public Response signalToContainer(
+      @PathParam(RMWSConsts.CONTAINERID) String containerId,
+      @PathParam(RMWSConsts.COMMAND) String command,
+      @Context HttpServletRequest hsr)
+      throws AuthorizationException {
+    UserGroupInformation callerUGI = getCallerUserGroupInformation(hsr, true);
+    initForWritableEndpoints(callerUGI, true);
+    if (!EnumUtils.isValidEnum(
+        SignalContainerCommand.class, command.toUpperCase())) {
+      String errMsg =
+          "Invalid command: " + command.toUpperCase() + ", valid commands are: "
+              + Arrays.asList(SignalContainerCommand.values());
+      return Response.status(Status.BAD_REQUEST).entity(errMsg).build();
+    }
+    try {
+      ContainerId containerIdObj = ContainerId.fromString(containerId);
+      rm.getClientRMService().signalToContainer(SignalContainerRequest
+          .newInstance(containerIdObj,
+              SignalContainerCommand.valueOf(command.toUpperCase())));
+    } catch (Exception e) {
+      return Response.status(Status.INTERNAL_SERVER_ERROR)
+          .entity(e.getMessage()).build();
+    }
+    return Response.status(Status.OK).build();
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/TestRMWebServicesContainers.java

@@ -0,0 +1,158 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.yarn.server.resourcemanager.webapp;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.io.IOException;
+import javax.ws.rs.core.MediaType;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.http.JettyUtils;
+import org.apache.hadoop.security.UserGroupInformation;
+import org.apache.hadoop.yarn.api.records.SignalContainerCommand;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.server.resourcemanager.MockNM;
+import org.apache.hadoop.yarn.server.resourcemanager.MockRM;
+import org.apache.hadoop.yarn.server.resourcemanager.ResourceManager;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.RMApp;
+import org.apache.hadoop.yarn.server.resourcemanager.rmapp.attempt.RMAppAttemptState;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.ResourceScheduler;
+import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fifo.FifoScheduler;
+import org.apache.hadoop.yarn.webapp.GenericExceptionHandler;
+import org.apache.hadoop.yarn.webapp.GuiceServletConfig;
+import org.apache.hadoop.yarn.webapp.JerseyTestBase;
+import org.eclipse.jetty.server.Response;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.google.inject.Guice;
+import com.google.inject.servlet.ServletModule;
+import com.sun.jersey.api.client.ClientResponse;
+import com.sun.jersey.api.client.WebResource;
+import com.sun.jersey.guice.spi.container.servlet.GuiceContainer;
+import com.sun.jersey.test.framework.WebAppDescriptor;
+
+/**
+ * Testing containers REST API.
+ */
+public class TestRMWebServicesContainers extends JerseyTestBase {
+
+  private static MockRM rm;
+  private static String userName;
+
+  private static class WebServletModule extends ServletModule {
+    @Override
+    protected void configureServlets() {
+      bind(JAXBContextResolver.class);
+      bind(RMWebServices.class);
+      bind(GenericExceptionHandler.class);
+      try {
+        userName = UserGroupInformation.getCurrentUser().getShortUserName();
+      } catch (IOException ioe) {
+        throw new RuntimeException("Unable to get current user name "
+            + ioe.getMessage(), ioe);
+      }
+      Configuration conf = new Configuration();
+      conf.setClass(YarnConfiguration.RM_SCHEDULER, FifoScheduler.class,
+          ResourceScheduler.class);
+      conf.set(YarnConfiguration.YARN_ADMIN_ACL, userName);
+      rm = new MockRM(conf);
+      bind(ResourceManager.class).toInstance(rm);
+      serve("/*").with(GuiceContainer.class);
+      filter("/*").through(TestRMWebServicesAppsModification
+          .TestRMCustomAuthFilter.class);
+    }
+  }
+
+  static {
+    GuiceServletConfig.setInjector(
+        Guice.createInjector(new WebServletModule()));
+  }
+
+  @Before
+  @Override
+  public void setUp() throws Exception {
+    super.setUp();
+    GuiceServletConfig.setInjector(
+        Guice.createInjector(new WebServletModule()));
+  }
+
+  public TestRMWebServicesContainers() {
+    super(new WebAppDescriptor.Builder(
+        "org.apache.hadoop.yarn.server.resourcemanager.webapp")
+        .contextListenerClass(GuiceServletConfig.class)
+        .filterClass(com.google.inject.servlet.GuiceFilter.class)
+        .contextPath("jersey-guice-filter").servletPath("/").build());
+  }
+
+  @Test
+  public void testSignalContainer() throws Exception {
+    rm.start();
+    MockNM nm = rm.registerNode("127.0.0.1:1234", 2048);
+    RMApp app = rm.submitApp(1024);
+    nm.nodeHeartbeat(true);
+    MockRM
+        .waitForState(app.getCurrentAppAttempt(), RMAppAttemptState.ALLOCATED);
+    rm.sendAMLaunched(app.getCurrentAppAttempt().getAppAttemptId());
+    WebResource r = resource();
+
+    // test error command
+    ClientResponse response =
+        r.path("ws").path("v1").path("cluster").path("containers").path(
+            app.getCurrentAppAttempt().getMasterContainer().getId().toString())
+            .path("signal")
+            .path("not-exist-signal")
+            .queryParam("user.name", userName)
+            .accept(MediaType.APPLICATION_JSON).post(ClientResponse.class);
+    assertEquals(MediaType.APPLICATION_JSON_TYPE + "; " + JettyUtils.UTF_8,
+        response.getType().toString());
+    assertEquals(Response.SC_BAD_REQUEST, response.getStatus());
+    assertTrue(response.getEntity(String.class)
+        .contains("Invalid command: NOT-EXIST-SIGNAL"));
+
+    // test error containerId
+    response =
+        r.path("ws").path("v1").path("cluster").path("containers").path("XXX")
+            .path("signal")
+            .path(SignalContainerCommand.OUTPUT_THREAD_DUMP.name())
+            .queryParam("user.name", userName)
+            .accept(MediaType.APPLICATION_JSON).post(ClientResponse.class);
+    assertEquals(MediaType.APPLICATION_JSON_TYPE + "; " + JettyUtils.UTF_8,
+        response.getType().toString());
+    assertEquals(Response.SC_INTERNAL_SERVER_ERROR, response.getStatus());
+    assertTrue(
+        response.getEntity(String.class).contains("Invalid ContainerId"));
+
+    // test correct signal
+    response =
+        r.path("ws").path("v1").path("cluster").path("containers").path(
+            app.getCurrentAppAttempt().getMasterContainer().getId().toString())
+            .path("signal")
+            .path(SignalContainerCommand.OUTPUT_THREAD_DUMP.name())
+            .queryParam("user.name", userName)
+            .accept(MediaType.APPLICATION_JSON).post(ClientResponse.class);
+    assertEquals(MediaType.APPLICATION_JSON_TYPE + "; " + JettyUtils.UTF_8,
+        response.getType().toString());
+    assertEquals(Response.SC_OK, response.getStatus());
+
+    rm.stop();
+  }
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/webapp/DefaultRequestInterceptorREST.java

@@ -543,4 +543,13 @@ public class DefaultRequestInterceptorREST
         + "is correct");
   }
 
+  @Override
+  public Response signalToContainer(String containerId, String command,
+      HttpServletRequest req) throws AuthorizationException {
+    return RouterWebServiceUtil
+        .genericForward(webAppAddress, req, Response.class, HTTPMethods.POST,
+            RMWSConsts.RM_WEB_SERVICE_PATH + "/" + RMWSConsts.CONTAINERS + "/"
+                + containerId + "/" + RMWSConsts.SIGNAL + "/" + command, null,
+            null);
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/webapp/FederationInterceptorREST.java

@@ -1342,6 +1342,12 @@ public class FederationInterceptorREST extends AbstractRESTRequestInterceptor {
         + "is correct");
   }
 
+  @Override
+  public Response signalToContainer(String containerId, String command,
+      HttpServletRequest req) {
+    throw new NotImplementedException("Code is not implemented");
+  }
+
   @Override
   public void shutdown() {
     if (threadpool != null) {

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/webapp/RouterWebServices.java

@@ -934,4 +934,18 @@ public class RouterWebServices implements RMWebServiceProtocol {
     this.response = response;
   }
 
+  @POST
+  @Path(RMWSConsts.SIGNAL_TO_CONTAINER)
+  @Produces({ MediaType.APPLICATION_JSON + "; " + JettyUtils.UTF_8,
+      MediaType.APPLICATION_XML + "; " + JettyUtils.UTF_8 })
+  public Response signalToContainer(
+      @PathParam(RMWSConsts.CONTAINERID) String containerId,
+      @PathParam(RMWSConsts.COMMAND) String command,
+      @Context HttpServletRequest req)
+      throws AuthorizationException {
+    init();
+    RequestInterceptorChainWrapper pipeline = getInterceptorChain(req);
+    return pipeline.getRootInterceptor()
+        .signalToContainer(containerId, command, req);
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/webapp/MockRESTRequestInterceptor.java

@@ -359,4 +359,10 @@ public class MockRESTRequestInterceptor extends AbstractRESTRequestInterceptor {
       String containerId) {
     return new ContainerInfo();
   }
+
+  @Override
+  public Response signalToContainer(String containerId, String command,
+      HttpServletRequest req) {
+    return Response.status(Status.OK).build();
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/webapp/PassThroughRESTRequestInterceptor.java

@@ -363,4 +363,10 @@ public class PassThroughRESTRequestInterceptor
     return getNextInterceptor().updateApplicationTimeout(appTimeout, hsr,
         appId);
   }
+
+  @Override
+  public Response signalToContainer(String containerId,
+      String command, HttpServletRequest req) throws AuthorizationException {
+    return getNextInterceptor().signalToContainer(containerId, command, req);
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/ResourceManagerRest.md

@@ -5291,3 +5291,57 @@ Response Header:
       HTTP/1.1 200 OK
       Content-Type: application/xml
       Transfer-Encoding: chunked
+
+
+Cluster Container Signal API
+--------------------------------
+
+With the Container Signal API, you can send a signal to a specified container with one of the following commands: OUTPUT_THREAD_DUMP, GRACEFUL_SHUTDOWN and FORCEFUL_SHUTDOWN.
+
+### URI
+
+      http://rm-http-address:port/ws/v1/cluster/containers/{containerId}/signal/{command}
+
+### HTTP Operations Supported
+
+      POST
+
+### Query Parameters Supported
+
+      None
+
+### Response Examples
+
+**JSON response**
+
+HTTP Request:
+
+      POST http://rm-http-address:port/ws/v1/cluster/containers/container_1531404209605_0008_01_000001/signal/OUTPUT_THREAD_DUMP
+      Accept: application/json
+      Content-Type: application/json
+
+Response Header:
+
+      HTTP/1.1 200 OK
+      Content-Type: application/json
+      Transfer-Encoding: chunked
+      Server: Jetty(6.1.26)
+
+No response body.
+
+**XML response**
+
+HTTP Request:
+
+      POST http://rm-http-address:port/ws/v1/cluster/containers/container_1531404209605_0008_01_000001/signal/OUTPUT_THREAD_DUMP
+      Accept: application/xml
+      Content-Type: application/xml
+
+Response Header:
+
+      HTTP/1.1 200 OK
+      Content-Type: application/xml
+      Content-Length: 552
+      Server: Jetty(6.1.26)
+
+No response body.