YARN-6108. Improve AHS webservice to accept NM address as a parameter to get container logs. Contributed by Xuan Gong.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/webapp/util/YarnWebServiceUtils.java

@@ -0,0 +1,62 @@
+/**
+* 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.webapp.util;
+
+import com.sun.jersey.api.client.Client;
+import com.sun.jersey.api.client.ClientHandlerException;
+import com.sun.jersey.api.client.ClientResponse;
+import com.sun.jersey.api.client.UniformInterfaceException;
+import com.sun.jersey.api.client.WebResource;
+import javax.ws.rs.core.MediaType;
+import org.apache.hadoop.conf.Configuration;
+import org.codehaus.jettison.json.JSONObject;
+
+/**
+ * This class contains several utility function which could be used to generate
+ * Restful calls to RM/NM/AHS.
+ *
+ */
+public final class YarnWebServiceUtils {
+
+  private YarnWebServiceUtils() {}
+
+  /**
+   * Utility function to get NodeInfo by calling RM WebService.
+   * @param conf the configuration
+   * @param nodeId the nodeId
+   * @return a JSONObject which contains the NodeInfo
+   * @throws ClientHandlerException if there is an error
+   *         processing the response.
+   * @throws UniformInterfaceException if the response status
+   *         is 204 (No Content).
+   */
+  public static JSONObject getNodeInfoFromRMWebService(Configuration conf,
+      String nodeId) throws ClientHandlerException,
+      UniformInterfaceException {
+    Client webServiceClient = Client.create();
+    String webAppAddress = WebAppUtils.getRMWebAppURLWithScheme(conf);
+
+    WebResource webResource = webServiceClient.resource(webAppAddress);
+
+    ClientResponse response = webResource.path("ws").path("v1")
+        .path("cluster").path("nodes")
+        .path(nodeId).accept(MediaType.APPLICATION_JSON)
+        .get(ClientResponse.class);
+    return response.getEntity(JSONObject.class);
+  }
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-applicationhistoryservice/src/main/java/org/apache/hadoop/yarn/server/applicationhistoryservice/webapp/AHSWebServices.java

@@ -41,6 +41,8 @@ import javax.ws.rs.core.Response;
 import javax.ws.rs.core.StreamingOutput;
 import javax.ws.rs.core.Response.ResponseBuilder;
 import javax.ws.rs.core.Response.Status;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience.Private;
 import org.apache.hadoop.classification.InterfaceAudience.Public;
 import org.apache.hadoop.classification.InterfaceStability.Unstable;
@@ -56,6 +58,7 @@ import org.apache.hadoop.yarn.logaggregation.ContainerLogMeta;
 import org.apache.hadoop.yarn.logaggregation.ContainerLogType;
 import org.apache.hadoop.yarn.logaggregation.LogToolUtils;
 import org.apache.hadoop.yarn.server.webapp.WebServices;
+import org.apache.hadoop.yarn.server.webapp.YarnWebServiceParams;
 import org.apache.hadoop.yarn.server.webapp.dao.AppAttemptInfo;
 import org.apache.hadoop.yarn.server.webapp.dao.AppAttemptsInfo;
 import org.apache.hadoop.yarn.server.webapp.dao.AppInfo;
@@ -67,15 +70,21 @@ import org.apache.hadoop.yarn.util.timeline.TimelineUtils;
 import org.apache.hadoop.yarn.webapp.BadRequestException;
 import org.apache.hadoop.yarn.webapp.NotFoundException;
 import org.apache.hadoop.yarn.webapp.util.WebAppUtils;
+import org.apache.hadoop.yarn.webapp.util.YarnWebServiceUtils;
+import org.codehaus.jettison.json.JSONException;
+import org.codehaus.jettison.json.JSONObject;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Joiner;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
+import com.sun.jersey.api.client.ClientHandlerException;
+import com.sun.jersey.api.client.UniformInterfaceException;
 
 @Singleton
 @Path("/ws/v1/applicationhistory")
 public class AHSWebServices extends WebServices {
 
+  private static final Log LOG = LogFactory.getLog(AHSWebServices.class);
   private static final String NM_DOWNLOAD_URI_STR =
       "/ws/v1/node/containers";
   private static final Joiner JOINER = Joiner.on("");
@@ -224,6 +233,8 @@ public class AHSWebServices extends WebServices {
    *    HttpServletResponse
    * @param containerIdStr
    *    The container ID
+   * @param nmId
+   *    The Node Manager NodeId
    * @return
    *    The log file's name and current file size
    */
@@ -233,7 +244,8 @@ public class AHSWebServices extends WebServices {
   public Response getContainerLogsInfo(
       @Context HttpServletRequest req,
       @Context HttpServletResponse res,
-      @PathParam("containerid") String containerIdStr) {
+      @PathParam(YarnWebServiceParams.CONTAINER_ID) String containerIdStr,
+      @QueryParam(YarnWebServiceParams.NM_ID) String nmId) {
     ContainerId containerId = null;
     init(res);
     try {
@@ -258,21 +270,43 @@ public class AHSWebServices extends WebServices {
     }
     if (isRunningState(appInfo.getAppState())) {
       String appOwner = appInfo.getUser();
-      ContainerInfo containerInfo;
-      try {
-        containerInfo = super.getContainer(
-            req, res, appId.toString(),
-            containerId.getApplicationAttemptId().toString(),
-            containerId.toString());
-      } catch (Exception ex) {
-        // return log meta for the aggregated logs if exists.
-        // It will also return empty log meta for the local logs.
-        return getContainerLogMeta(appId, appOwner, null,
-            containerIdStr, true);
+      String nodeHttpAddress = null;
+      if (nmId != null && !nmId.isEmpty()) {
+        try {
+          nodeHttpAddress = getNMWebAddressFromRM(conf, nmId);
+        } catch (Exception ex) {
+          if (LOG.isDebugEnabled()) {
+            LOG.debug(ex.getMessage());
+          }
+        }
+      }
+      if (nodeHttpAddress == null || nodeHttpAddress.isEmpty()) {
+        ContainerInfo containerInfo;
+        try {
+          containerInfo = super.getContainer(
+              req, res, appId.toString(),
+              containerId.getApplicationAttemptId().toString(),
+              containerId.toString());
+        } catch (Exception ex) {
+          // return log meta for the aggregated logs if exists.
+          // It will also return empty log meta for the local logs.
+          return getContainerLogMeta(appId, appOwner, null,
+              containerIdStr, true);
+        }
+        nodeHttpAddress = containerInfo.getNodeHttpAddress();
+        // make sure nodeHttpAddress is not null and not empty. Otherwise,
+        // we would only get log meta for aggregated logs instead of
+        // re-directing the request
+        if (nodeHttpAddress == null || nodeHttpAddress.isEmpty()) {
+          // return log meta for the aggregated logs if exists.
+          // It will also return empty log meta for the local logs.
+          return getContainerLogMeta(appId, appOwner, null,
+              containerIdStr, true);
+        }
       }
-      String nodeHttpAddress = containerInfo.getNodeHttpAddress();
       String uri = "/" + containerId.toString() + "/logs";
-      String resURI = JOINER.join(nodeHttpAddress, NM_DOWNLOAD_URI_STR, uri);
+      String resURI = JOINER.join(getAbsoluteNMWebAddress(nodeHttpAddress),
+          NM_DOWNLOAD_URI_STR, uri);
       String query = req.getQueryString();
       if (query != null && !query.isEmpty()) {
         resURI += "?" + query;
@@ -302,6 +336,8 @@ public class AHSWebServices extends WebServices {
    *    The content type
    * @param size
    *    the size of the log file
+   * @param nmId
+   *    The Node Manager NodeId
    * @return
    *    The contents of the container's log file
    */
@@ -312,11 +348,13 @@ public class AHSWebServices extends WebServices {
   @Unstable
   public Response getContainerLogFile(@Context HttpServletRequest req,
       @Context HttpServletResponse res,
-      @PathParam("containerid") String containerIdStr,
-      @PathParam("filename") String filename,
-      @QueryParam("format") String format,
-      @QueryParam("size") String size) {
-    return getLogs(req, res, containerIdStr, filename, format, size);
+      @PathParam(YarnWebServiceParams.CONTAINER_ID) String containerIdStr,
+      @PathParam(YarnWebServiceParams.CONTAINER_LOG_FILE_NAME) String filename,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_FORMAT) String format,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_SIZE) String size,
+      @QueryParam(YarnWebServiceParams.NM_ID) String nmId) {
+    return getLogs(req, res, containerIdStr, filename, format,
+        size, nmId);
   }
 
   //TODO: YARN-4993: Refactory ContainersLogsBlock, AggregatedLogsBlock and
@@ -329,10 +367,11 @@ public class AHSWebServices extends WebServices {
   @Unstable
   public Response getLogs(@Context HttpServletRequest req,
       @Context HttpServletResponse res,
-      @PathParam("containerid") String containerIdStr,
-      @PathParam("filename") String filename,
-      @QueryParam("format") String format,
-      @QueryParam("size") String size) {
+      @PathParam(YarnWebServiceParams.CONTAINER_ID) String containerIdStr,
+      @PathParam(YarnWebServiceParams.CONTAINER_LOG_FILE_NAME) String filename,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_FORMAT) String format,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_SIZE) String size,
+      @QueryParam(YarnWebServiceParams.NM_ID) String nmId) {
     init(res);
     ContainerId containerId;
     try {
@@ -362,20 +401,41 @@ public class AHSWebServices extends WebServices {
     }
 
     if (isRunningState(appInfo.getAppState())) {
-      ContainerInfo containerInfo;
-      try {
-        containerInfo = super.getContainer(
-            req, res, appId.toString(),
-            containerId.getApplicationAttemptId().toString(),
-            containerId.toString());
-      } catch (Exception ex) {
-        // output the aggregated logs
-        return sendStreamOutputResponse(appId, appOwner, null, containerIdStr,
-            filename, format, length, true);
+      String nodeHttpAddress = null;
+      if (nmId != null && !nmId.isEmpty()) {
+        try {
+          nodeHttpAddress = getNMWebAddressFromRM(conf, nmId);
+        } catch (Exception ex) {
+          if (LOG.isDebugEnabled()) {
+            LOG.debug(ex.getMessage());
+          }
+        }
+      }
+      if (nodeHttpAddress == null || nodeHttpAddress.isEmpty()) {
+        ContainerInfo containerInfo;
+        try {
+          containerInfo = super.getContainer(
+              req, res, appId.toString(),
+              containerId.getApplicationAttemptId().toString(),
+              containerId.toString());
+        } catch (Exception ex) {
+          // output the aggregated logs
+          return sendStreamOutputResponse(appId, appOwner, null,
+              containerIdStr, filename, format, length, true);
+        }
+        nodeHttpAddress = containerInfo.getNodeHttpAddress();
+        // make sure nodeHttpAddress is not null and not empty. Otherwise,
+        // we would only get aggregated logs instead of re-directing the
+        // request
+        if (nodeHttpAddress == null || nodeHttpAddress.isEmpty()) {
+          // output the aggregated logs
+          return sendStreamOutputResponse(appId, appOwner, null,
+              containerIdStr, filename, format, length, true);
+        }
       }
-      String nodeHttpAddress = containerInfo.getNodeHttpAddress();
       String uri = "/" + containerId.toString() + "/logs/" + filename;
-      String resURI = JOINER.join(nodeHttpAddress, NM_DOWNLOAD_URI_STR, uri);
+      String resURI = JOINER.join(getAbsoluteNMWebAddress(nodeHttpAddress),
+          NM_DOWNLOAD_URI_STR, uri);
       String query = req.getQueryString();
       if (query != null && !query.isEmpty()) {
         resURI += "?" + query;
@@ -482,7 +542,7 @@ public class AHSWebServices extends WebServices {
           .getContainerLogMetaFromRemoteFS(conf, appId, containerIdStr,
               nodeId, appOwner);
       if (containerLogMeta.isEmpty()) {
-        return createBadResponse(Status.INTERNAL_SERVER_ERROR,
+        throw new NotFoundException(
             "Can not get log meta for container: " + containerIdStr);
       }
       List<ContainerLogsInfo> containersLogsInfo = new ArrayList<>();
@@ -518,4 +578,23 @@ public class AHSWebServices extends WebServices {
         + "re-direct the request to related NodeManager "
         + "for local container logs.";
   }
+
+  private String getAbsoluteNMWebAddress(String nmWebAddress) {
+    if (nmWebAddress.contains(WebAppUtils.HTTP_PREFIX) ||
+        nmWebAddress.contains(WebAppUtils.HTTPS_PREFIX)) {
+      return nmWebAddress;
+    }
+    return WebAppUtils.getHttpSchemePrefix(conf) + nmWebAddress;
+  }
+
+  @VisibleForTesting
+  @Private
+  public String getNMWebAddressFromRM(Configuration configuration,
+      String nodeId) throws ClientHandlerException,
+      UniformInterfaceException, JSONException {
+    JSONObject nodeInfo = YarnWebServiceUtils.getNodeInfoFromRMWebService(
+        configuration, nodeId).getJSONObject("node");
+    return nodeInfo.has("nodeHTTPAddress") ?
+        nodeInfo.getString("nodeHTTPAddress") : null;
+  }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-applicationhistoryservice/src/test/java/org/apache/hadoop/yarn/server/applicationhistoryservice/webapp/TestAHSWebServices.java

@@ -62,6 +62,7 @@ import org.apache.hadoop.yarn.server.security.ApplicationACLsManager;
 import org.apache.hadoop.yarn.server.timeline.TimelineDataManager;
 import org.apache.hadoop.yarn.server.timeline.TimelineStore;
 import org.apache.hadoop.yarn.server.timeline.security.TimelineACLsManager;
+import org.apache.hadoop.yarn.server.webapp.YarnWebServiceParams;
 import org.apache.hadoop.yarn.server.webapp.dao.ContainerLogsInfo;
 import org.apache.hadoop.yarn.api.records.timeline.TimelineAbout;
 import org.apache.hadoop.yarn.util.timeline.TimelineUtils;
@@ -84,6 +85,7 @@ import org.junit.runners.Parameterized;
 import com.google.inject.Guice;
 import com.google.inject.Singleton;
 import com.google.inject.servlet.ServletModule;
+import com.sun.jersey.api.client.ClientHandlerException;
 import com.sun.jersey.api.client.ClientResponse;
 import com.sun.jersey.api.client.ClientResponse.Status;
 import com.sun.jersey.api.client.GenericType;
@@ -103,6 +105,8 @@ public class TestAHSWebServices extends JerseyTestBase {
   private static FileSystem fs;
   private static final String remoteLogRootDir = "target/logs/";
   private static final String rootLogDir = "target/LocalLogs";
+  private static final String NM_WEBADDRESS = "test-nm-web-address:9999";
+  private static final String NM_ID = "test:1234";
 
   @BeforeClass
   public static void setupClass() throws Exception {
@@ -130,7 +134,17 @@ public class TestAHSWebServices extends JerseyTestBase {
     };
     historyClientService.init(conf);
     historyClientService.start();
-    ahsWebservice = new AHSWebServices(historyClientService, conf);
+    ahsWebservice = new AHSWebServices(historyClientService, conf) {
+      @Override
+      public String getNMWebAddressFromRM(Configuration configuration,
+          String nodeId) throws ClientHandlerException,
+          UniformInterfaceException, JSONException {
+        if (nodeId.equals(NM_ID)) {
+          return NM_WEBADDRESS;
+        }
+        return null;
+      }
+    };
     fs = FileSystem.get(conf);
     GuiceServletConfig.setInjector(
         Guice.createInjector(new WebServletModule()));
@@ -676,6 +690,22 @@ public class TestAHSWebServices extends JerseyTestBase {
     assertTrue(redirectURL.contains("/logs/" + fileName));
     assertTrue(redirectURL.contains("user.name=" + user));
 
+    // If we specify NM id, we would re-direct the request
+    // to this NM's Web Address.
+    requestURI = r.path("ws").path("v1")
+        .path("applicationhistory").path("containerlogs")
+        .path(containerId1.toString()).path(fileName)
+        .queryParam("user.name", user)
+        .queryParam(YarnWebServiceParams.NM_ID, NM_ID)
+        .getURI();
+    redirectURL = getRedirectURL(requestURI.toString());
+    assertTrue(redirectURL != null);
+    assertTrue(redirectURL.contains(NM_WEBADDRESS));
+    assertTrue(redirectURL.contains("ws/v1/node/containers"));
+    assertTrue(redirectURL.contains(containerId1.toString()));
+    assertTrue(redirectURL.contains("/logs/" + fileName));
+    assertTrue(redirectURL.contains("user.name=" + user));
+
     // Test with new API
     requestURI = r.path("ws").path("v1")
         .path("applicationhistory").path("containers")
@@ -689,6 +719,20 @@ public class TestAHSWebServices extends JerseyTestBase {
     assertTrue(redirectURL.contains("/logs/" + fileName));
     assertTrue(redirectURL.contains("user.name=" + user));
 
+    requestURI = r.path("ws").path("v1")
+        .path("applicationhistory").path("containers")
+        .path(containerId1.toString()).path("logs").path(fileName)
+        .queryParam("user.name", user)
+        .queryParam(YarnWebServiceParams.NM_ID, NM_ID)
+        .getURI();
+    redirectURL = getRedirectURL(requestURI.toString());
+    assertTrue(redirectURL != null);
+    assertTrue(redirectURL.contains(NM_WEBADDRESS));
+    assertTrue(redirectURL.contains("ws/v1/node/containers"));
+    assertTrue(redirectURL.contains(containerId1.toString()));
+    assertTrue(redirectURL.contains("/logs/" + fileName));
+    assertTrue(redirectURL.contains("user.name=" + user));
+
     // If we can not container information from ATS, we would try to
     // get aggregated log from remote FileSystem.
     ContainerId containerId1000 = ContainerId.newContainerId(
@@ -710,6 +754,21 @@ public class TestAHSWebServices extends JerseyTestBase {
     // the warning message.
     assertTrue(responseText.contains("LogType: " + ContainerLogType.LOCAL));
     assertTrue(responseText.contains(AHSWebServices.getNoRedirectWarning()));
+
+    // If we can not container information from ATS, and we specify the NM id,
+    // but we can not get nm web address, we would still try to
+    // get aggregated log from remote FileSystem.
+    response = r.path("ws").path("v1")
+        .path("applicationhistory").path("containerlogs")
+        .path(containerId1000.toString()).path(fileName)
+        .queryParam(YarnWebServiceParams.NM_ID, "invalid-nm:1234")
+        .queryParam("user.name", user)
+        .accept(MediaType.TEXT_PLAIN)
+        .get(ClientResponse.class);
+    responseText = response.getEntity(String.class);
+    assertTrue(responseText.contains(content));
+    assertTrue(responseText.contains("LogType: " + ContainerLogType.LOCAL));
+    assertTrue(responseText.contains(AHSWebServices.getNoRedirectWarning()));
   }
 
   @Test(timeout = 10000)
@@ -721,21 +780,38 @@ public class TestAHSWebServices extends JerseyTestBase {
         ApplicationAttemptId.newInstance(appId, 1);
     ContainerId containerId1 = ContainerId.newContainerId(appAttemptId, 1);
     WebResource r = resource();
-    // If we can get Container information from ATS, we re-direct the request
-    // to the nodemamager who runs the container.
+    // If we specify the NMID, we re-direct the request by using
+    // the NM's web address
     URI requestURI = r.path("ws").path("v1")
         .path("applicationhistory").path("containers")
         .path(containerId1.toString()).path("logs")
-        .queryParam("user.name", user).getURI();
+        .queryParam("user.name", user)
+        .queryParam(YarnWebServiceParams.NM_ID, NM_ID)
+        .getURI();
     String redirectURL = getRedirectURL(requestURI.toString());
     assertTrue(redirectURL != null);
+    assertTrue(redirectURL.contains(NM_WEBADDRESS));
+    assertTrue(redirectURL.contains("ws/v1/node/containers"));
+    assertTrue(redirectURL.contains(containerId1.toString()));
+    assertTrue(redirectURL.contains("/logs"));
+
+    // If we do not specify the NodeId but can get Container information
+    // from ATS, we re-direct the request to the node manager
+    // who runs the container.
+    requestURI = r.path("ws").path("v1")
+        .path("applicationhistory").path("containers")
+        .path(containerId1.toString()).path("logs")
+        .queryParam("user.name", user).getURI();
+    redirectURL = getRedirectURL(requestURI.toString());
+    assertTrue(redirectURL != null);
     assertTrue(redirectURL.contains("test:1234"));
     assertTrue(redirectURL.contains("ws/v1/node/containers"));
     assertTrue(redirectURL.contains(containerId1.toString()));
     assertTrue(redirectURL.contains("/logs"));
 
-    // If we can not container information from ATS, we would try to
-    // get aggregated log meta from remote FileSystem.
+    // If we can not container information from ATS,
+    // and not specify nodeId,
+    // we would try to get aggregated log meta from remote FileSystem.
     ContainerId containerId1000 = ContainerId.newContainerId(
         appAttemptId, 1000);
     String fileName = "syslog";
@@ -765,6 +841,32 @@ public class TestAHSWebServices extends JerseyTestBase {
         assertEquals(logInfo.getLogType(), ContainerLogType.LOCAL.toString());
       }
     }
+
+    // If we can not container information from ATS,
+    // and we specify NM id, but can not find NM WebAddress for this nodeId,
+    // we would still try to get aggregated log meta from remote FileSystem.
+    response = r.path("ws").path("v1")
+        .path("applicationhistory").path("containers")
+        .path(containerId1000.toString()).path("logs")
+        .queryParam(YarnWebServiceParams.NM_ID, "invalid-nm:1234")
+        .queryParam("user.name", user)
+        .accept(MediaType.APPLICATION_JSON)
+        .get(ClientResponse.class);
+    responseText = response.getEntity(new GenericType<
+        List<ContainerLogsInfo>>(){});
+    assertTrue(responseText.size() == 2);
+    for (ContainerLogsInfo logInfo : responseText) {
+      if(logInfo.getLogType().equals(ContainerLogType.AGGREGATED.toString())) {
+        List<PerContainerLogFileInfo> logMeta = logInfo
+            .getContainerLogsInfo();
+        assertTrue(logMeta.size() == 1);
+        assertEquals(logMeta.get(0).getFileName(), fileName);
+        assertEquals(logMeta.get(0).getFileSize(), String.valueOf(
+            content.length()));
+      } else {
+        assertEquals(logInfo.getLogType(), ContainerLogType.LOCAL.toString());
+      }
+    }
   }
 
   @Test(timeout = 10000)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-common/src/main/java/org/apache/hadoop/yarn/server/webapp/YarnWebServiceParams.java

@@ -0,0 +1,37 @@
+/**
+* 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.webapp;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+
+/**
+ * Common web service parameters which could be used in
+ * RM/NM/AHS WebService.
+ *
+ */
+@InterfaceAudience.LimitedPrivate({"YARN"})
+public interface YarnWebServiceParams {
+
+  // the params used in container-log related web services
+  String CONTAINER_ID = "containerid";
+  String CONTAINER_LOG_FILE_NAME = "filename";
+  String RESPONSE_CONTENT_FORMAT = "format";
+  String RESPONSE_CONTENT_SIZE = "size";
+  String NM_ID = "nm.id";
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/webapp/NMWebServices.java

@@ -68,6 +68,7 @@ import org.apache.hadoop.yarn.server.nodemanager.webapp.dao.ContainerInfo;
 import org.apache.hadoop.yarn.server.nodemanager.webapp.dao.NMContainerLogsInfo;
 import org.apache.hadoop.yarn.server.nodemanager.webapp.dao.ContainersInfo;
 import org.apache.hadoop.yarn.server.nodemanager.webapp.dao.NodeInfo;
+import org.apache.hadoop.yarn.server.webapp.YarnWebServiceParams;
 import org.apache.hadoop.yarn.server.webapp.dao.ContainerLogsInfo;
 import org.apache.hadoop.yarn.util.Times;
 import org.apache.hadoop.yarn.webapp.BadRequestException;
@@ -235,7 +236,7 @@ public class NMWebServices {
   public Response getContainerLogsInfo(
       @javax.ws.rs.core.Context HttpServletRequest hsr,
       @javax.ws.rs.core.Context HttpServletResponse res,
-      @PathParam("containerid") String containerIdStr) {
+      @PathParam(YarnWebServiceParams.CONTAINER_ID) String containerIdStr) {
     ContainerId containerId = null;
     init();
     try {
@@ -307,10 +308,14 @@ public class NMWebServices {
   @Public
   @Unstable
   public Response getContainerLogFile(
-      @PathParam("containerid") String containerIdStr,
-      @PathParam("filename") String filename,
-      @QueryParam("format") String format,
-      @QueryParam("size") String size) {
+      @PathParam(YarnWebServiceParams.CONTAINER_ID)
+      final String containerIdStr,
+      @PathParam(YarnWebServiceParams.CONTAINER_LOG_FILE_NAME)
+      String filename,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_FORMAT)
+      String format,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_SIZE)
+      String size) {
     return getLogs(containerIdStr, filename, format, size);
   }
 
@@ -338,10 +343,14 @@ public class NMWebServices {
   @Public
   @Unstable
   public Response getLogs(
-      @PathParam("containerid") final String containerIdStr,
-      @PathParam("filename") String filename,
-      @QueryParam("format") String format,
-      @QueryParam("size") String size) {
+      @PathParam(YarnWebServiceParams.CONTAINER_ID)
+      final String containerIdStr,
+      @PathParam(YarnWebServiceParams.CONTAINER_LOG_FILE_NAME)
+      String filename,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_FORMAT)
+      String format,
+      @QueryParam(YarnWebServiceParams.RESPONSE_CONTENT_SIZE)
+      String size) {
     ContainerId tempContainerId;
     try {
       tempContainerId = ContainerId.fromString(containerIdStr);