Revert "HDFS-15423 RBF: WebHDFS create shouldn't choose DN from all sub-clusters (#2605)" (#2900)

This reverts commit cb3ed32fe0.

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterWebHdfsMethods.java

@@ -93,7 +93,6 @@
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.TokenIdentifier;
-import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -105,8 +104,6 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Random;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
 /**
  * WebHDFS Router implementation. This is an extension of
@@ -456,33 +453,21 @@ private DatanodeInfo chooseDatanode(final Router router,
       final String path, final HttpOpParam.Op op, final long openOffset,
       final String excludeDatanodes) throws IOException {
     final RouterRpcServer rpcServer = getRPCServer(router);
-    DatanodeInfo[] dns = {};
+    DatanodeInfo[] dns = null;
-    String resolvedNs = "";
     try {
       dns = rpcServer.getCachedDatanodeReport(DatanodeReportType.LIVE);
     } catch (IOException e) {
       LOG.error("Cannot get the datanodes from the RPC server", e);
     }
 
-    if (op == PutOpParam.Op.CREATE) {
-      try {
-        resolvedNs = rpcServer.getCreateLocation(path).getNameserviceId();
-      } catch (IOException e) {
-        LOG.error("Cannot get the name service " +
-            "to create file for path {} ", path, e);
-      }
-    }
-
     HashSet<Node> excludes = new HashSet<Node>();
+    if (excludeDatanodes != null) {
       Collection<String> collection =
           getTrimmedStringCollection(excludeDatanodes);
       for (DatanodeInfo dn : dns) {
-      String ns = getNsFromDataNodeNetworkLocation(dn.getNetworkLocation());
         if (collection.contains(dn.getName())) {
           excludes.add(dn);
-      } else if (op == PutOpParam.Op.CREATE && !ns.equals(resolvedNs)) {
+        }
-        // for CREATE, the dest dn should be in the resolved ns
-        excludes.add(dn);
       }
     }
 
@@ -517,22 +502,6 @@ private DatanodeInfo chooseDatanode(final Router router,
     return getRandomDatanode(dns, excludes);
   }
 
-  /**
-   * Get the nameservice info from datanode network location.
-   * @param location network location with format `/ns0/rack1`
-   * @return nameservice this datanode is in
-   */
-  @VisibleForTesting
-  public static String getNsFromDataNodeNetworkLocation(String location) {
-    // network location should be in the format of /ns/rack
-    Pattern pattern = Pattern.compile("^/([^/]*)/");
-    Matcher matcher = pattern.matcher(location);
-    if (matcher.find()) {
-      return matcher.group(1);
-    }
-    return "";
-  }
-
   /**
    * Get a random Datanode from a subcluster.
    * @param dns Nodes to be chosen from.

hadoop-hdfs-project/hadoop-hdfs-rbf/src/test/java/org/apache/hadoop/fs/contract/router/web/RouterWebHDFSContract.java

@@ -64,8 +64,6 @@ public static void createCluster(Configuration conf) throws IOException {
       conf.addResource(CONTRACT_WEBHDFS_XML);
 
       cluster = new MiniRouterDFSCluster(true, 2, conf);
-      cluster.setIndependentDNs();
-      cluster.setNumDatanodesPerNameservice(3);
 
       // Start NNs and DNs and wait until ready
       cluster.startCluster(conf);

hadoop-hdfs-project/hadoop-hdfs-rbf/src/test/java/org/apache/hadoop/hdfs/server/federation/MiniRouterDFSCluster.java

@@ -774,15 +774,6 @@ public void startCluster(Configuration overrideConf) {
       }
       topology.setFederation(true);
 
-      // Generate conf for namenodes and datanodes
-      String ns0 = nameservices.get(0);
-      Configuration nnConf = generateNamenodeConfiguration(ns0);
-      if (overrideConf != null) {
-        nnConf.addResource(overrideConf);
-        // Router also uses this configurations as initial values.
-        routerConf = new Configuration(overrideConf);
-      }
-
       // Set independent DNs across subclusters
       int numDNs = nameservices.size() * numDatanodesPerNameservice;
       Configuration[] dnConfs = null;
@@ -790,7 +781,7 @@ public void startCluster(Configuration overrideConf) {
         dnConfs = new Configuration[numDNs];
         int dnId = 0;
         for (String nsId : nameservices) {
-          Configuration subclusterConf = new Configuration(nnConf);
+          Configuration subclusterConf = new Configuration();
           subclusterConf.set(DFS_INTERNAL_NAMESERVICES_KEY, nsId);
           for (int i = 0; i < numDatanodesPerNameservice; i++) {
             dnConfs[dnId] = subclusterConf;
@@ -800,6 +791,14 @@ public void startCluster(Configuration overrideConf) {
       }
 
       // Start mini DFS cluster
+      String ns0 = nameservices.get(0);
+      Configuration nnConf = generateNamenodeConfiguration(ns0);
+      if (overrideConf != null) {
+        nnConf.addResource(overrideConf);
+        // Router also uses this configurations as initial values.
+        routerConf = new Configuration(overrideConf);
+      }
+
       cluster = new MiniDFSCluster.Builder(nnConf)
           .numDataNodes(numDNs)
           .nnTopology(topology)

hadoop-hdfs-project/hadoop-hdfs-rbf/src/test/java/org/apache/hadoop/hdfs/server/federation/router/TestRouterWebHdfsMethods.java

@@ -1,147 +0,0 @@
-/**
- * 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.hdfs.server.federation.router;
-
-import static org.apache.hadoop.hdfs.server.federation.FederationTestUtils.createMountTableEntry;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.fail;
-
-import java.io.FileNotFoundException;
-import java.net.HttpURLConnection;
-import java.net.URL;
-import java.util.Collections;
-
-import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.fs.FileSystem;
-import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.server.federation.MiniRouterDFSCluster.RouterContext;
-import org.apache.hadoop.hdfs.server.federation.RouterConfigBuilder;
-import org.apache.hadoop.hdfs.server.federation.StateStoreDFSCluster;
-import org.apache.hadoop.hdfs.server.federation.resolver.order.DestinationOrder;
-import org.junit.AfterClass;
-import org.junit.BeforeClass;
-import org.junit.Test;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-/**
- * Test suite for Router Web Hdfs methods.
- */
-public class TestRouterWebHdfsMethods {
-  static final Logger LOG =
-      LoggerFactory.getLogger(TestRouterWebHdfsMethods.class);
-
-  private static StateStoreDFSCluster cluster;
-  private static RouterContext router;
-  private static String httpUri;
-
-  @BeforeClass
-  public static void globalSetUp() throws Exception {
-    cluster = new StateStoreDFSCluster(false, 2);
-    Configuration conf = new RouterConfigBuilder()
-        .stateStore()
-        .rpc()
-        .http()
-        .admin()
-        .build();
-    cluster.addRouterOverrides(conf);
-    cluster.startCluster();
-    cluster.startRouters();
-    cluster.waitClusterUp();
-    router = cluster.getRandomRouter();
-    httpUri = "http://"+router.getHttpAddress();
-  }
-
-  @AfterClass
-  public static void tearDown() {
-    if (cluster != null) {
-      cluster.shutdown();
-      cluster = null;
-    }
-  }
-
-  @Test
-  public void testWebHdfsCreate() throws Exception {
-    // the file is created at default ns (ns0)
-    String path = "/tmp/file";
-    URL url = new URL(getUri(path));
-    LOG.info("URL: {}", url);
-    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
-    conn.setRequestMethod("PUT");
-    assertEquals(HttpURLConnection.HTTP_CREATED, conn.getResponseCode());
-    verifyFile("ns0", path, true);
-    verifyFile("ns1", path, false);
-    conn.disconnect();
-  }
-
-  @Test
-  public void testWebHdfsCreateWithMounts() throws Exception {
-    // the file is created at mounted ns (ns1)
-    String mountPoint = "/tmp-ns1";
-    String path = "/tmp-ns1/file";
-    createMountTableEntry(
-        router.getRouter(), mountPoint,
-        DestinationOrder.RANDOM, Collections.singletonList("ns1"));
-    URL url = new URL(getUri(path));
-    LOG.info("URL: {}", url);
-    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
-    conn.setRequestMethod("PUT");
-    assertEquals(HttpURLConnection.HTTP_CREATED, conn.getResponseCode());
-    verifyFile("ns1", path, true);
-    verifyFile("ns0", path, false);
-    conn.disconnect();
-  }
-
-  private String getUri(String path) {
-    final String user = System.getProperty("user.name");
-    final StringBuilder uri = new StringBuilder(httpUri);
-    uri.append("/webhdfs/v1").
-        append(path).
-        append("?op=CREATE").
-        append("&user.name=" + user);
-    return uri.toString();
-  }
-
-  private void verifyFile(String ns, String path, boolean shouldExist)
-      throws Exception {
-    FileSystem fs = cluster.getNamenode(ns, null).getFileSystem();
-    try {
-      fs.getFileStatus(new Path(path));
-      if (!shouldExist) {
-        fail(path + " should not exist in ns " + ns);
-      }
-    } catch (FileNotFoundException e) {
-      if (shouldExist) {
-        fail(path + " should exist in ns " + ns);
-      }
-    }
-  }
-
-  @Test
-  public void testGetNsFromDataNodeNetworkLocation() {
-    assertEquals("ns0", RouterWebHdfsMethods
-        .getNsFromDataNodeNetworkLocation("/ns0/rack-info1"));
-    assertEquals("ns0", RouterWebHdfsMethods
-        .getNsFromDataNodeNetworkLocation("/ns0/row1/rack-info1"));
-    assertEquals("", RouterWebHdfsMethods
-        .getNsFromDataNodeNetworkLocation("/row0"));
-    assertEquals("", RouterWebHdfsMethods
-        .getNsFromDataNodeNetworkLocation("whatever-rack-info1"));
-  }
-}