From 7bd96751466caaba61ef9409fc2509d5d23990bf Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Sun, 1 May 2022 23:29:26 -0700
Subject: [PATCH 01/17] YARN-11122:Implement the method of getting ClusterNode,
 including related Metrics

---
 .../yarn/server/router/RouterMetrics.java     | 29 ++++++++++++++++-
 .../clientrm/FederationClientInterceptor.java | 29 +++++++++++++++--
 .../clientrm/RouterYarnClientUtils.java       | 31 ++++++++++++++-----
 3 files changed, 79 insertions(+), 10 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
index 271d1fead5546..902a6551afc29 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
@@ -55,6 +55,8 @@ public final class RouterMetrics {
   private MutableGaugeInt numAppAttemptsFailedRetrieved;
   @Metric("# of getClusterMetrics failed to be retrieved")
   private MutableGaugeInt numGetClusterMetricsFailedRetrieved;
+  @Metric("# of getClusterNodes failed to be retrieved")
+  private MutableGaugeInt numGetClusterNodesFailedRetrieved;
 
   // Aggregate metrics are shared, and don't have to be looked up per call
   @Metric("Total number of successful Submitted apps and latency(ms)")
@@ -74,7 +76,9 @@ public final class RouterMetrics {
   @Metric("Total number of successful Retrieved getClusterMetrics and "
       + "latency(ms)")
   private MutableRate totalSucceededGetClusterMetricsRetrieved;
-
+  @Metric("Total number of successful Retrieved getClusterNodes and "
+          + "latency(ms)")
+  private MutableRate totalSucceededGetClusterNodesRetrieved;
 
   /**
    * Provide quantile counters for all latencies.
@@ -86,6 +90,7 @@ public final class RouterMetrics {
   private MutableQuantiles getApplicationsReportLatency;
   private MutableQuantiles getApplicationAttemptReportLatency;
   private MutableQuantiles getClusterMetricsLatency;
+  private MutableQuantiles getClusterNodesLatency;
 
   private static volatile RouterMetrics INSTANCE = null;
   private static MetricsRegistry registry;
@@ -112,6 +117,10 @@ private RouterMetrics() {
     getClusterMetricsLatency =
         registry.newQuantiles("getClusterMetricsLatency",
             "latency of get cluster metrics", "ops", "latency", 10);
+
+    getClusterNodesLatency =
+            registry.newQuantiles("getClusterNodesLatency",
+                    "latency of get cluster nodes", "ops", "latency", 10);
   }
 
   public static RouterMetrics getMetrics() {
@@ -168,6 +177,11 @@ public long getNumSucceededGetClusterMetricsRetrieved(){
     return totalSucceededGetClusterMetricsRetrieved.lastStat().numSamples();
   }
 
+  @VisibleForTesting
+  public long getNumSucceededGetClusterNodesRetrieved(){
+    return totalSucceededGetClusterNodesRetrieved.lastStat().numSamples();
+  }
+
   @VisibleForTesting
   public double getLatencySucceededAppsCreated() {
     return totalSucceededAppsCreated.lastStat().mean();
@@ -203,6 +217,11 @@ public double getLatencySucceededGetClusterMetricsRetrieved() {
     return totalSucceededGetClusterMetricsRetrieved.lastStat().mean();
   }
 
+  @VisibleForTesting
+  public double getLatencySucceededGetClusterNodesRetrieved() {
+    return totalSucceededGetClusterNodesRetrieved.lastStat().mean();
+  }
+
   @VisibleForTesting
   public int getAppsFailedCreated() {
     return numAppsFailedCreated.value();
@@ -273,6 +292,11 @@ public void succeededGetClusterMetricsRetrieved(long duration) {
     getClusterMetricsLatency.add(duration);
   }
 
+  public void succeededGetClusterNodesRetrieved(long duration) {
+    totalSucceededGetClusterNodesRetrieved.add(duration);
+    getClusterNodesLatency.add(duration);
+  }
+
   public void incrAppsFailedCreated() {
     numAppsFailedCreated.incr();
   }
@@ -301,4 +325,7 @@ public void incrGetClusterMetricsFailedRetrieved() {
     numGetClusterMetricsFailedRetrieved.incr();
   }
 
+  public void incrClusterNodesFailedRetrieved() {
+    numGetClusterNodesFailedRetrieved.incr();
+  }
 }
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
index de80a35f49b78..721e7797d688a 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
@@ -18,6 +18,7 @@
 
 package org.apache.hadoop.yarn.server.router.clientrm;
 
+import org.apache.hadoop.thirdparty.com.google.common.collect.Maps;
 import org.apache.hadoop.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
 import java.io.IOException;
 import java.lang.reflect.Method;
@@ -790,8 +791,32 @@ <R> Map<SubClusterId, R> invokeConcurrent(Collection<SubClusterId> clusterIds,
 
   @Override
   public GetClusterNodesResponse getClusterNodes(GetClusterNodesRequest request)
-      throws YarnException, IOException {
-    throw new NotImplementedException("Code is not implemented");
+          throws YarnException, IOException {
+    if (request == null) {
+      routerMetrics.incrClusterNodesFailedRetrieved();
+      RouterServerUtil.logAndThrowException(
+              "Missing getClusterNodes request.", null);
+    }
+    long startTime = clock.getTime();
+    Map<SubClusterId, SubClusterInfo> subclusters =
+            federationFacade.getSubClusters(true);
+    Map<SubClusterId, GetClusterNodesResponse> clusterNodes = Maps.newHashMap();
+    for (Map.Entry<SubClusterId, SubClusterInfo> entry : subclusters.entrySet()) {
+      SubClusterId subClusterId = entry.getKey();
+      ApplicationClientProtocol client = null;
+      try {
+        client = getClientRMProxyForSubCluster(subClusterId);
+        GetClusterNodesResponse response = client.getClusterNodes(request);
+        clusterNodes.put(subClusterId, response);
+      } catch (Exception ex) {
+        routerMetrics.incrClusterNodesFailedRetrieved();
+        LOG.error("Unable to get cluster nodes due to exception.", ex);
+      }
+    }
+    long stopTime = clock.getTime();
+    routerMetrics.succeededGetClusterNodesRetrieved(stopTime - startTime);
+    // Merge the NodesResponse
+    return RouterYarnClientUtils.mergeClusterNodesResponse(clusterNodes.values());
   }
 
   @Override
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
index 934636b104df6..76fa384a012ed 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
@@ -17,17 +17,14 @@
  */
 package org.apache.hadoop.yarn.server.router.clientrm;
 
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.Map;
+import java.util.*;
 
 import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationsResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetClusterMetricsResponse;
-import org.apache.hadoop.yarn.api.records.ApplicationId;
-import org.apache.hadoop.yarn.api.records.ApplicationReport;
-import org.apache.hadoop.yarn.api.records.ApplicationResourceUsageReport;
-import org.apache.hadoop.yarn.api.records.YarnClusterMetrics;
+import org.apache.hadoop.yarn.api.protocolrecords.GetClusterNodesResponse;
+import org.apache.hadoop.yarn.api.records.*;
 import org.apache.hadoop.yarn.server.uam.UnmanagedApplicationManager;
+import org.apache.hadoop.yarn.util.Records;
 import org.apache.hadoop.yarn.util.resource.Resources;
 
 /**
@@ -194,4 +191,24 @@ private static boolean mergeUamToReport(String appName,
     return !(appName.startsWith(UnmanagedApplicationManager.APP_NAME) ||
         appName.startsWith(PARTIAL_REPORT));
   }
+
+  /**
+   * Merges a list of GetClusterNodesResponse.
+   *
+   * @param responses a list of GetClusterNodesResponse to merge
+   * @return the merged GetClusterNodesResponse
+   */
+  public static GetClusterNodesResponse mergeClusterNodesResponse(
+          Collection<GetClusterNodesResponse> responses) {
+    GetClusterNodesResponse clusterNodesResponse = Records.newRecord(
+            GetClusterNodesResponse.class);
+    List<NodeReport> nodeReports = new ArrayList<>();
+    for (GetClusterNodesResponse response : responses) {
+      if (response != null && response.getNodeReports() != null) {
+        nodeReports.addAll(response.getNodeReports());
+      }
+    }
+    clusterNodesResponse.setNodeReports(nodeReports);
+    return clusterNodesResponse;
+  }
 }

From 2af73f56a71f2e87a6c00a9c8c5755e87897da8a Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Fri, 6 May 2022 19:59:03 -0700
Subject: [PATCH 02/17] YARN-11122: Finish Juint Test With getClusterNodes

---
 .../TestFederationClientInterceptor.java      | 30 ++++++++++---------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
index 74d10a44c52b5..7eb1f6b5f37f4 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
@@ -30,20 +30,7 @@
 
 import org.apache.hadoop.test.LambdaTestUtils;
 import org.apache.hadoop.yarn.MockApps;
-import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationAttemptReportRequest;
-import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationAttemptReportResponse;
-import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationReportRequest;
-import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationReportResponse;
-import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationsRequest;
-import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationsResponse;
-import org.apache.hadoop.yarn.api.protocolrecords.GetClusterMetricsRequest;
-import org.apache.hadoop.yarn.api.protocolrecords.GetClusterMetricsResponse;
-import org.apache.hadoop.yarn.api.protocolrecords.GetNewApplicationRequest;
-import org.apache.hadoop.yarn.api.protocolrecords.GetNewApplicationResponse;
-import org.apache.hadoop.yarn.api.protocolrecords.KillApplicationRequest;
-import org.apache.hadoop.yarn.api.protocolrecords.KillApplicationResponse;
-import org.apache.hadoop.yarn.api.protocolrecords.SubmitApplicationRequest;
-import org.apache.hadoop.yarn.api.protocolrecords.SubmitApplicationResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.*;
 import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;
@@ -641,4 +628,19 @@ public void testGetApplicationsApplicationStateNotExists() throws Exception{
     Assert.assertNotNull(responseGet);
     Assert.assertTrue(responseGet.getApplicationList().isEmpty());
   }
+
+  @Test
+  public void testGetClusterNodesRequest() throws Exception {
+    LOG.info("Test FederationClientInterceptor : Get Cluster Nodeds request");
+    // null request
+    LambdaTestUtils.intercept(YarnException.class,
+            "Missing getClusterNodes request.",
+            () -> interceptor.getClusterNodes(null));
+
+    // normal request.
+    GetClusterNodesResponse response =
+            interceptor.getClusterNodes(GetClusterNodesRequest.newInstance());
+    Assert.assertEquals(subClusters.size(),
+            response.getNodeReports().size());
+  }
 }

From 87277d1549e101b6e0ea490e979bccd38a4d5b02 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Sat, 7 May 2022 01:08:13 -0700
Subject: [PATCH 03/17] YARN-11122:Fix CheckStyle

---
 .../TestFederationClientInterceptor.java        | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
index 7eb1f6b5f37f4..3180fd6502514 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
@@ -30,7 +30,22 @@
 
 import org.apache.hadoop.test.LambdaTestUtils;
 import org.apache.hadoop.yarn.MockApps;
-import org.apache.hadoop.yarn.api.protocolrecords.*;
+import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationAttemptReportRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationAttemptReportResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationReportRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationReportResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationsRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationsResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.GetClusterMetricsRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.GetClusterMetricsResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.GetNewApplicationRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.GetNewApplicationResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.KillApplicationRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.KillApplicationResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.SubmitApplicationRequest;
+import org.apache.hadoop.yarn.api.protocolrecords.SubmitApplicationResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.GetClusterNodesResponse;
+import org.apache.hadoop.yarn.api.protocolrecords.GetClusterNodesRequest;
 import org.apache.hadoop.yarn.api.records.ApplicationAttemptId;
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.api.records.ApplicationSubmissionContext;

From 6630ce6df52e3a0e696e0d95f10a404168cbe17c Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Sat, 7 May 2022 16:04:11 -0700
Subject: [PATCH 04/17] YARN-11122:Fix CheckStyle

---
 .../router/clientrm/TestFederationClientInterceptor.java       | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
index 3180fd6502514..a41aa14ec6ac5 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
@@ -649,8 +649,7 @@ public void testGetClusterNodesRequest() throws Exception {
     LOG.info("Test FederationClientInterceptor : Get Cluster Nodeds request");
     // null request
     LambdaTestUtils.intercept(YarnException.class,
-            "Missing getClusterNodes request.",
-            () -> interceptor.getClusterNodes(null));
+            "Missing getClusterNodes request.", () -> interceptor.getClusterNodes(null));
 
     // normal request.
     GetClusterNodesResponse response =

From 07f609015cfbaac4d21b498e2f23149719c36a27 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Mon, 9 May 2022 20:17:07 -0700
Subject: [PATCH 05/17] YARN-11122. Fix CheckStyle.

---
 .../hadoop/yarn/server/router/RouterMetrics.java     |  3 +--
 .../router/clientrm/RouterYarnClientUtils.java       | 12 ++++++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
index 902a6551afc29..0230fdfe2bb83 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
@@ -76,8 +76,7 @@ public final class RouterMetrics {
   @Metric("Total number of successful Retrieved getClusterMetrics and "
       + "latency(ms)")
   private MutableRate totalSucceededGetClusterMetricsRetrieved;
-  @Metric("Total number of successful Retrieved getClusterNodes and "
-          + "latency(ms)")
+  @Metric("Total number of successful Retrieved getClusterNodes and latency(ms)")
   private MutableRate totalSucceededGetClusterNodesRetrieved;
 
   /**
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
index 76fa384a012ed..28b64b28538d0 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
@@ -17,12 +17,20 @@
  */
 package org.apache.hadoop.yarn.server.router.clientrm;
 
-import java.util.*;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.List;
+import java.util.ArrayList;
 
 import org.apache.hadoop.yarn.api.protocolrecords.GetApplicationsResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetClusterMetricsResponse;
 import org.apache.hadoop.yarn.api.protocolrecords.GetClusterNodesResponse;
-import org.apache.hadoop.yarn.api.records.*;
+import org.apache.hadoop.yarn.api.records.ApplicationId;
+import org.apache.hadoop.yarn.api.records.ApplicationReport;
+import org.apache.hadoop.yarn.api.records.ApplicationResourceUsageReport;
+import org.apache.hadoop.yarn.api.records.YarnClusterMetrics;
+import org.apache.hadoop.yarn.api.records.NodeReport;
 import org.apache.hadoop.yarn.server.uam.UnmanagedApplicationManager;
 import org.apache.hadoop.yarn.util.Records;
 import org.apache.hadoop.yarn.util.resource.Resources;

From 1bf7332b463894d563ec9ac57154ff74b0cee914 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Tue, 10 May 2022 15:28:51 -0700
Subject: [PATCH 06/17] YARN-11122. Fix CheckStyle

---
 .../server/router/clientrm/RouterYarnClientUtils.java  | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
index 28b64b28538d0..44a9f6f92d662 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
@@ -203,14 +203,16 @@ private static boolean mergeUamToReport(String appName,
   /**
    * Merges a list of GetClusterNodesResponse.
    *
-   * @param responses a list of GetClusterNodesResponse to merge
-   * @return the merged GetClusterNodesResponse
+   * @param responses a list of GetClusterNodesResponse to merge.
+   * @return the merged GetClusterNodesResponse.
    */
   public static GetClusterNodesResponse mergeClusterNodesResponse(
           Collection<GetClusterNodesResponse> responses) {
-    GetClusterNodesResponse clusterNodesResponse = Records.newRecord(
-            GetClusterNodesResponse.class);
+
+    GetClusterNodesResponse clusterNodesResponse = Records.newRecord(GetClusterNodesResponse.class);
+
     List<NodeReport> nodeReports = new ArrayList<>();
+
     for (GetClusterNodesResponse response : responses) {
       if (response != null && response.getNodeReports() != null) {
         nodeReports.addAll(response.getNodeReports());

From b4867c0d12d30cd8f000ace87053b19641fafd27 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Wed, 11 May 2022 23:43:38 -0700
Subject: [PATCH 07/17] YARN-11122: Fix Code Style, indentation

---
 .../hadoop/yarn/server/router/RouterMetrics.java    |  2 +-
 .../clientrm/FederationClientInterceptor.java       | 13 ++++++-------
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
index 0230fdfe2bb83..f2fc945901d0e 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
@@ -118,7 +118,7 @@ private RouterMetrics() {
             "latency of get cluster metrics", "ops", "latency", 10);
 
     getClusterNodesLatency =
-            registry.newQuantiles("getClusterNodesLatency",
+        registry.newQuantiles("getClusterNodesLatency",
                     "latency of get cluster nodes", "ops", "latency", 10);
   }
 
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
index 721e7797d688a..e2f055fb80b12 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
@@ -791,19 +791,17 @@ <R> Map<SubClusterId, R> invokeConcurrent(Collection<SubClusterId> clusterIds,
 
   @Override
   public GetClusterNodesResponse getClusterNodes(GetClusterNodesRequest request)
-          throws YarnException, IOException {
+      throws YarnException, IOException {
     if (request == null) {
       routerMetrics.incrClusterNodesFailedRetrieved();
-      RouterServerUtil.logAndThrowException(
-              "Missing getClusterNodes request.", null);
+      RouterServerUtil.logAndThrowException("Missing getClusterNodes request.", null);
     }
     long startTime = clock.getTime();
-    Map<SubClusterId, SubClusterInfo> subclusters =
+    Map<SubClusterId, SubClusterInfo> subClusters =
             federationFacade.getSubClusters(true);
     Map<SubClusterId, GetClusterNodesResponse> clusterNodes = Maps.newHashMap();
-    for (Map.Entry<SubClusterId, SubClusterInfo> entry : subclusters.entrySet()) {
-      SubClusterId subClusterId = entry.getKey();
-      ApplicationClientProtocol client = null;
+    for (SubClusterId subClusterId : subClusters.keySet()) {
+      ApplicationClientProtocol client;
       try {
         client = getClientRMProxyForSubCluster(subClusterId);
         GetClusterNodesResponse response = client.getClusterNodes(request);
@@ -811,6 +809,7 @@ public GetClusterNodesResponse getClusterNodes(GetClusterNodesRequest request)
       } catch (Exception ex) {
         routerMetrics.incrClusterNodesFailedRetrieved();
         LOG.error("Unable to get cluster nodes due to exception.", ex);
+        throw ex;
       }
     }
     long stopTime = clock.getTime();

From aa49c3a788a026bfb9443974ba67784142fa2303 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 00:05:03 -0700
Subject: [PATCH 08/17] YARN-11122: Add GetClusterNodes Metric Junit Test.

---
 .../yarn/server/router/RouterMetrics.java     |  5 +++
 .../yarn/server/router/TestRouterMetrics.java | 34 +++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
index f2fc945901d0e..9a2498a7016fe 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
@@ -256,6 +256,11 @@ public int getClusterMetricsFailedRetrieved() {
     return numGetClusterMetricsFailedRetrieved.value();
   }
 
+  @VisibleForTesting
+  public int getClusterNodesFailedRetrieved() {
+    return numGetClusterNodesFailedRetrieved.value();
+  }
+
   public void succeededAppsCreated(long duration) {
     totalSucceededAppsCreated.add(duration);
     getNewApplicationLatency.add(duration);
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
index 4d4838a560b48..2cde7aa0bad02 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
@@ -346,6 +346,11 @@ public void getClusterMetrics() {
       LOG.info("Mocked: failed getClusterMetrics call");
       metrics.incrGetClusterMetricsFailedRetrieved();
     }
+
+    public void getClusterNodes() {
+      LOG.info("Mocked: failed getClusterNodes call");
+      metrics.incrClusterNodesFailedRetrieved();
+    }
   }
 
   // Records successes for all calls
@@ -392,5 +397,34 @@ public void getClusterMetrics(long duration){
               duration);
       metrics.succeededGetClusterMetricsRetrieved(duration);
     }
+
+    public void getClusterNodes(long duration) {
+      LOG.info("Mocked: successful getClusterNodes call with duration {}",
+              duration);
+      metrics.succeededGetClusterNodesRetrieved(duration);
+    }
+  }
+
+  @Test
+  public void testSucceededGetClusterNodes() {
+    long totalGoodBefore = metrics.getNumSucceededGetClusterNodesRetrieved();
+    goodSubCluster.getClusterNodes(150);
+    Assert.assertEquals(totalGoodBefore + 1,
+            metrics.getNumSucceededGetClusterNodesRetrieved());
+    Assert.assertEquals(150, metrics.getLatencySucceededGetClusterNodesRetrieved(),
+            0);
+    goodSubCluster.getClusterNodes(300);
+    Assert.assertEquals(totalGoodBefore + 2,
+            metrics.getNumSucceededGetClusterNodesRetrieved());
+    Assert.assertEquals(225, metrics.getLatencySucceededGetClusterNodesRetrieved(),
+            0);
+  }
+
+  @Test
+  public void testGetClusterNodesFailed() {
+    long totalBadBefore = metrics.getClusterNodesFailedRetrieved();
+    badSubCluster.getClusterNodes();
+    Assert.assertEquals(totalBadBefore + 1,
+            metrics.getClusterNodesFailedRetrieved());
   }
 }

From c6e404bbfd417e1f474348d82c0052d05f829a33 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 00:59:56 -0700
Subject: [PATCH 09/17] YARN-11122: Fix CodeStyle.

---
 .../yarn/server/router/TestRouterMetrics.java       | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
index 2cde7aa0bad02..5ee11923c74d9 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
@@ -399,8 +399,7 @@ public void getClusterMetrics(long duration){
     }
 
     public void getClusterNodes(long duration) {
-      LOG.info("Mocked: successful getClusterNodes call with duration {}",
-              duration);
+      LOG.info("Mocked: successful getClusterNodes call with duration {}", duration);
       metrics.succeededGetClusterNodesRetrieved(duration);
     }
   }
@@ -410,14 +409,14 @@ public void testSucceededGetClusterNodes() {
     long totalGoodBefore = metrics.getNumSucceededGetClusterNodesRetrieved();
     goodSubCluster.getClusterNodes(150);
     Assert.assertEquals(totalGoodBefore + 1,
-            metrics.getNumSucceededGetClusterNodesRetrieved());
+        metrics.getNumSucceededGetClusterNodesRetrieved());
     Assert.assertEquals(150, metrics.getLatencySucceededGetClusterNodesRetrieved(),
-            0);
+         0);
     goodSubCluster.getClusterNodes(300);
     Assert.assertEquals(totalGoodBefore + 2,
-            metrics.getNumSucceededGetClusterNodesRetrieved());
+        metrics.getNumSucceededGetClusterNodesRetrieved());
     Assert.assertEquals(225, metrics.getLatencySucceededGetClusterNodesRetrieved(),
-            0);
+        0);
   }
 
   @Test
@@ -425,6 +424,6 @@ public void testGetClusterNodesFailed() {
     long totalBadBefore = metrics.getClusterNodesFailedRetrieved();
     badSubCluster.getClusterNodes();
     Assert.assertEquals(totalBadBefore + 1,
-            metrics.getClusterNodesFailedRetrieved());
+        metrics.getClusterNodesFailedRetrieved());
   }
 }

From c7ccca5bfdd9aa5a5ccadcfd63b9209da0573296 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 01:09:58 -0700
Subject: [PATCH 10/17] YARN-11122: Fix CodeStyle.

---
 .../org/apache/hadoop/yarn/server/router/RouterMetrics.java     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
index 9a2498a7016fe..a30009f233d3d 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/RouterMetrics.java
@@ -119,7 +119,7 @@ private RouterMetrics() {
 
     getClusterNodesLatency =
         registry.newQuantiles("getClusterNodesLatency",
-                    "latency of get cluster nodes", "ops", "latency", 10);
+            "latency of get cluster nodes", "ops", "latency", 10);
   }
 
   public static RouterMetrics getMetrics() {

From 407c0393cb3d34ddffda27a6a9794a6c13005772 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 01:14:55 -0700
Subject: [PATCH 11/17] YARN-11122: Fix CodeStyle.

---
 .../yarn/server/router/clientrm/RouterYarnClientUtils.java    | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
index 44a9f6f92d662..54289169f1781 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
@@ -207,10 +207,8 @@ private static boolean mergeUamToReport(String appName,
    * @return the merged GetClusterNodesResponse.
    */
   public static GetClusterNodesResponse mergeClusterNodesResponse(
-          Collection<GetClusterNodesResponse> responses) {
-
+      Collection<GetClusterNodesResponse> responses) {
     GetClusterNodesResponse clusterNodesResponse = Records.newRecord(GetClusterNodesResponse.class);
-
     List<NodeReport> nodeReports = new ArrayList<>();
 
     for (GetClusterNodesResponse response : responses) {

From 7845199609d0de6dd91c63e27d90a1fdf2bd4936 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 01:32:54 -0700
Subject: [PATCH 12/17] YARN-11122: Fix CodeStyle.

---
 .../router/clientrm/TestFederationClientInterceptor.java | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
index a41aa14ec6ac5..6667ae6502132 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
@@ -648,13 +648,12 @@ public void testGetApplicationsApplicationStateNotExists() throws Exception{
   public void testGetClusterNodesRequest() throws Exception {
     LOG.info("Test FederationClientInterceptor : Get Cluster Nodeds request");
     // null request
-    LambdaTestUtils.intercept(YarnException.class,
-            "Missing getClusterNodes request.", () -> interceptor.getClusterNodes(null));
-
+    LambdaTestUtils.intercept(YarnException.class, "Missing getClusterNodes request.",
+        () -> interceptor.getClusterNodes(null));
     // normal request.
     GetClusterNodesResponse response =
-            interceptor.getClusterNodes(GetClusterNodesRequest.newInstance());
+        interceptor.getClusterNodes(GetClusterNodesRequest.newInstance());
     Assert.assertEquals(subClusters.size(),
-            response.getNodeReports().size());
+        response.getNodeReports().size());
   }
 }

From f16651fe443d92a368ab317d2e4de07a08908d95 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 01:44:00 -0700
Subject: [PATCH 13/17] YARN-11122: Fix CodeStyle.

---
 .../server/router/clientrm/FederationClientInterceptor.java     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
index e2f055fb80b12..6b6b19aac85ee 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/FederationClientInterceptor.java
@@ -798,7 +798,7 @@ public GetClusterNodesResponse getClusterNodes(GetClusterNodesRequest request)
     }
     long startTime = clock.getTime();
     Map<SubClusterId, SubClusterInfo> subClusters =
-            federationFacade.getSubClusters(true);
+        federationFacade.getSubClusters(true);
     Map<SubClusterId, GetClusterNodesResponse> clusterNodes = Maps.newHashMap();
     for (SubClusterId subClusterId : subClusters.keySet()) {
       ApplicationClientProtocol client;

From dde385a5fa4b4e50e07bfd762f3dc59e99aeef2f Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 01:50:45 -0700
Subject: [PATCH 14/17] YARN-11122: Fix CodeStyle.

---
 .../org/apache/hadoop/yarn/server/router/TestRouterMetrics.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
index 5ee11923c74d9..f47bf3c715108 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
@@ -411,7 +411,7 @@ public void testSucceededGetClusterNodes() {
     Assert.assertEquals(totalGoodBefore + 1,
         metrics.getNumSucceededGetClusterNodesRetrieved());
     Assert.assertEquals(150, metrics.getLatencySucceededGetClusterNodesRetrieved(),
-         0);
+        0);
     goodSubCluster.getClusterNodes(300);
     Assert.assertEquals(totalGoodBefore + 2,
         metrics.getNumSucceededGetClusterNodesRetrieved());

From 72359e0384e154322c10128135df6f0c60eec955 Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 04:21:21 -0700
Subject: [PATCH 15/17] YARN-11122. Fix CodeStyle.

---
 .../yarn/server/router/clientrm/RouterYarnClientUtils.java       | 1 -
 1 file changed, 1 deletion(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
index 54289169f1781..dfe20cfda1f3c 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/clientrm/RouterYarnClientUtils.java
@@ -210,7 +210,6 @@ public static GetClusterNodesResponse mergeClusterNodesResponse(
       Collection<GetClusterNodesResponse> responses) {
     GetClusterNodesResponse clusterNodesResponse = Records.newRecord(GetClusterNodesResponse.class);
     List<NodeReport> nodeReports = new ArrayList<>();
-
     for (GetClusterNodesResponse response : responses) {
       if (response != null && response.getNodeReports() != null) {
         nodeReports.addAll(response.getNodeReports());

From 0887df59dfb70c1f94d00262fab2e7219d994c2d Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 17:40:39 -0700
Subject: [PATCH 16/17] YARN-11122. Fix CodeStyle

---
 .../yarn/server/router/TestRouterMetrics.java   | 17 +++++++----------
 .../TestFederationClientInterceptor.java        |  3 +--
 2 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
index f47bf3c715108..52d256ee17345 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
@@ -38,6 +38,8 @@ public class TestRouterMetrics {
 
   private static RouterMetrics metrics = RouterMetrics.getMetrics();
 
+  private static final Double ASSERT_DOUBLE_DELTA = 0.01;
+
   @BeforeClass
   public static void init() {
 
@@ -408,22 +410,17 @@ public void getClusterNodes(long duration) {
   public void testSucceededGetClusterNodes() {
     long totalGoodBefore = metrics.getNumSucceededGetClusterNodesRetrieved();
     goodSubCluster.getClusterNodes(150);
-    Assert.assertEquals(totalGoodBefore + 1,
-        metrics.getNumSucceededGetClusterNodesRetrieved());
-    Assert.assertEquals(150, metrics.getLatencySucceededGetClusterNodesRetrieved(),
-        0);
+    Assert.assertEquals(totalGoodBefore + 1, metrics.getNumSucceededGetClusterNodesRetrieved());
+    Assert.assertEquals(150, metrics.getLatencySucceededGetClusterNodesRetrieved(), ASSERT_DOUBLE_DELTA);
     goodSubCluster.getClusterNodes(300);
-    Assert.assertEquals(totalGoodBefore + 2,
-        metrics.getNumSucceededGetClusterNodesRetrieved());
-    Assert.assertEquals(225, metrics.getLatencySucceededGetClusterNodesRetrieved(),
-        0);
+    Assert.assertEquals(totalGoodBefore + 2, metrics.getNumSucceededGetClusterNodesRetrieved());
+    Assert.assertEquals(225, metrics.getLatencySucceededGetClusterNodesRetrieved(), ASSERT_DOUBLE_DELTA);
   }
 
   @Test
   public void testGetClusterNodesFailed() {
     long totalBadBefore = metrics.getClusterNodesFailedRetrieved();
     badSubCluster.getClusterNodes();
-    Assert.assertEquals(totalBadBefore + 1,
-        metrics.getClusterNodesFailedRetrieved());
+    Assert.assertEquals(totalBadBefore + 1, metrics.getClusterNodesFailedRetrieved());
   }
 }
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
index 6667ae6502132..7409a1cff169f 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/clientrm/TestFederationClientInterceptor.java
@@ -653,7 +653,6 @@ public void testGetClusterNodesRequest() throws Exception {
     // normal request.
     GetClusterNodesResponse response =
         interceptor.getClusterNodes(GetClusterNodesRequest.newInstance());
-    Assert.assertEquals(subClusters.size(),
-        response.getNodeReports().size());
+    Assert.assertEquals(subClusters.size(), response.getNodeReports().size());
   }
 }

From dbd5cb323340e3597bedfd230df30313e0278fbd Mon Sep 17 00:00:00 2001
From: slfan1989 <louj1988@@>
Date: Thu, 12 May 2022 19:24:41 -0700
Subject: [PATCH 17/17] YARN-11122. Fix CodeStyle

---
 .../apache/hadoop/yarn/server/router/TestRouterMetrics.java | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
index 52d256ee17345..df8c194208aa2 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/test/java/org/apache/hadoop/yarn/server/router/TestRouterMetrics.java
@@ -411,10 +411,12 @@ public void testSucceededGetClusterNodes() {
     long totalGoodBefore = metrics.getNumSucceededGetClusterNodesRetrieved();
     goodSubCluster.getClusterNodes(150);
     Assert.assertEquals(totalGoodBefore + 1, metrics.getNumSucceededGetClusterNodesRetrieved());
-    Assert.assertEquals(150, metrics.getLatencySucceededGetClusterNodesRetrieved(), ASSERT_DOUBLE_DELTA);
+    Assert.assertEquals(150, metrics.getLatencySucceededGetClusterNodesRetrieved(),
+        ASSERT_DOUBLE_DELTA);
     goodSubCluster.getClusterNodes(300);
     Assert.assertEquals(totalGoodBefore + 2, metrics.getNumSucceededGetClusterNodesRetrieved());
-    Assert.assertEquals(225, metrics.getLatencySucceededGetClusterNodesRetrieved(), ASSERT_DOUBLE_DELTA);
+    Assert.assertEquals(225, metrics.getLatencySucceededGetClusterNodesRetrieved(),
+        ASSERT_DOUBLE_DELTA);
   }
 
   @Test