HDFS-12779. [READ] Allow cluster id to be specified to the Image generation tool

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/protocol/NamespaceInfo.java

@@ -160,6 +160,10 @@ public HAServiceState getState() {
     return state;
   }
 
+  public void setClusterID(String clusterID) {
+    this.clusterID = clusterID;
+  }
+
   @Override
   public String toString(){
     return super.toString() + ";bpid=" + blockPoolID;

hadoop-tools/hadoop-fs2img/src/main/java/org/apache/hadoop/hdfs/server/namenode/FileSystemImage.java

@@ -68,6 +68,7 @@ static Options options() {
     options.addOption("b", "blockclass", true, "Block output class");
     options.addOption("i", "blockidclass", true, "Block resolver class");
     options.addOption("c", "cachedirs", true, "Max active dirents");
+    options.addOption("cid", "clusterID", true, "Cluster ID");
     options.addOption("h", "help", false, "Print usage");
     return options;
   }
@@ -112,6 +113,9 @@ public int run(String[] argv) throws Exception {
       case "c":
         opts.cache(Integer.parseInt(o.getValue()));
         break;
+      case "cid":
+        opts.clusterID(o.getValue());
+        break;
       default:
         throw new UnsupportedOperationException("Internal error");
       }

hadoop-tools/hadoop-fs2img/src/main/java/org/apache/hadoop/hdfs/server/namenode/ImageWriter.java

@@ -126,13 +126,16 @@ public ImageWriter(Options opts) throws IOException {
           throw new IllegalStateException("Incompatible layout " +
               info.getLayoutVersion() + " (expected " + LAYOUT_VERSION);
         }
+        // set the cluster id, if given
+        if (opts.clusterID.length() > 0) {
+          info.setClusterID(opts.clusterID);
+        }
         stor.format(info);
         blockPoolID = info.getBlockPoolID();
       }
       outdir = new Path(tmp, "current");
       out = outfs.create(new Path(outdir, "fsimage_0000000000000000000"));
     } else {
-      // XXX necessary? writing a NNStorage now...
       outdir = null;
       outfs = null;
       out = opts.outStream;
@@ -517,6 +520,7 @@ public static class Options implements Configurable {
     private UGIResolver ugis;
     private Class<? extends UGIResolver> ugisClass;
     private BlockAliasMap<FileRegion> blocks;
+    private String clusterID;
 
     @SuppressWarnings("rawtypes")
     private Class<? extends BlockAliasMap> aliasMap;
@@ -543,6 +547,7 @@ public void setConf(Configuration conf) {
           NullBlockAliasMap.class, BlockAliasMap.class);
       blockIdsClass = conf.getClass(BLOCK_RESOLVER_CLASS,
           FixedBlockResolver.class, BlockResolver.class);
+      clusterID = "";
     }
 
     @Override
@@ -601,6 +606,10 @@ public Options blocks(Class<? extends BlockAliasMap> blocksClass) {
       return this;
     }
 
+    public Options clusterID(String clusterID) {
+      this.clusterID = clusterID;
+      return this;
+    }
   }
 
 }

hadoop-tools/hadoop-fs2img/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestNameNodeProvidedImplementation.java

@@ -155,11 +155,18 @@ public void shutdown() throws Exception {
 
   void createImage(TreeWalk t, Path out,
       Class<? extends BlockResolver> blockIdsClass) throws Exception {
+    createImage(t, out, blockIdsClass, "");
+  }
+
+  void createImage(TreeWalk t, Path out,
+      Class<? extends BlockResolver> blockIdsClass, String clusterID)
+      throws Exception {
     ImageWriter.Options opts = ImageWriter.defaults();
     opts.setConf(conf);
     opts.output(out.toString())
         .blocks(TextFileRegionAliasMap.class)
-        .blockIds(blockIdsClass);
+        .blockIds(blockIdsClass)
+        .clusterID(clusterID);
     try (ImageWriter w = new ImageWriter(opts)) {
       for (TreePath e : t) {
         w.accept(e);
@@ -562,4 +569,19 @@ private void verifyFileLocation(int fileIndex)
           dnInfos[0].getDatanodeUuid());
     }
   }
+
+  @Test
+  public void testSetClusterID() throws Exception {
+    String clusterID = "PROVIDED-CLUSTER";
+    createImage(new FSTreeWalk(NAMEPATH, conf), NNDIRPATH,
+        FixedBlockResolver.class, clusterID);
+    // 2 Datanodes, 1 PROVIDED and other DISK
+    startCluster(NNDIRPATH, 2, null,
+        new StorageType[][] {
+            {StorageType.PROVIDED},
+            {StorageType.DISK}},
+        false);
+    NameNode nn = cluster.getNameNode();
+    assertEquals(clusterID, nn.getNamesystem().getClusterId());
+  }
 }