HDFS-17180. HttpFS Add Support getTrashRoots API (#6028) Contributed by Hualong Zhang.

Reviewed-by: Shilun Fan <slfan1989@apache.org>
Signed-off-by: Shilun Fan <slfan1989@apache.org>

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/client/HttpFSFileSystem.java

@@ -148,6 +148,7 @@ public class HttpFSFileSystem extends FileSystem
   public static final String EC_POLICY_NAME_PARAM = "ecpolicy";
   public static final String OFFSET_PARAM = "offset";
   public static final String LENGTH_PARAM = "length";
+  public static final String ALLUSERS_PARAM = "allusers";
 
   public static final Short DEFAULT_PERMISSION = 0755;
   public static final String ACLSPEC_DEFAULT = "";
@@ -287,6 +288,7 @@ public enum Operation {
     GETSTATUS(HTTP_GET),
     GETECPOLICIES(HTTP_GET),
     GETECCODECS(HTTP_GET),
+    GETTRASHROOTS(HTTP_GET),
     GET_BLOCK_LOCATIONS(HTTP_GET);
 
     private String httpMethod;
@@ -1798,6 +1800,22 @@ public Map<String, String> getAllErasureCodingCodecs() throws IOException {
     return JsonUtilClient.getErasureCodeCodecs(json);
   }
 
+  public Collection<FileStatus> getTrashRoots(boolean allUsers) {
+    Map<String, String> params = new HashMap<String, String>();
+    params.put(OP_PARAM, Operation.GETTRASHROOTS.toString());
+    params.put(ALLUSERS_PARAM, Boolean.toString(allUsers));
+    Path path = new Path(getUri().toString(), "/");
+    try {
+      HttpURLConnection conn = getConnection(Operation.GETTRASHROOTS.getMethod(),
+          params, path, true);
+      HttpExceptionUtils.validateResponse(conn, HttpURLConnection.HTTP_OK);
+      JSONObject json = (JSONObject) HttpFSUtils.jsonParse(conn);
+      return JsonUtilClient.getTrashRoots(json);
+    } catch (IOException e) {
+      return super.getTrashRoots(allUsers);
+    }
+  }
+
   @VisibleForTesting
   static BlockLocation[] toBlockLocations(JSONObject json) throws IOException {
     ObjectMapper mapper = new ObjectMapper();

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/server/FSOperations.java

@@ -2396,4 +2396,32 @@ public Map execute(FileSystem fs) throws IOException {
       return ecCodecs;
     }
   }
+
+  /**
+   * Executor that performs a FSGetTrashRoots operation.
+   */
+  @InterfaceAudience.Private
+  public static class FSGetTrashRoots
+      implements FileSystemAccess.FileSystemExecutor<Map> {
+    final private boolean allUsers;
+
+    public FSGetTrashRoots(boolean allUsers) {
+      this.allUsers = allUsers;
+    }
+
+    @Override
+    public Map execute(FileSystem fs) throws IOException {
+      Map<String, Collection<FileStatus>> paths = new HashMap<>();
+      if (fs instanceof DistributedFileSystem) {
+        DistributedFileSystem dfs = (DistributedFileSystem) fs;
+        paths.put("Paths", dfs.getTrashRoots(allUsers));
+      } else {
+        throw new UnsupportedOperationException("getTrashRoots is " +
+            "not supported for HttpFs on " + fs.getClass() +
+            ". Please check your fs.defaultFS configuration");
+      }
+      HttpFSServerWebApp.get().getMetrics().incrOpsTrashRoots();
+      return paths;
+    }
+  }
 }

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/server/HttpFSParametersProvider.java

@@ -132,6 +132,7 @@ public class HttpFSParametersProvider extends ParametersProvider {
     PARAMS_DEF.put(Operation.GETSTATUS, new Class[]{});
     PARAMS_DEF.put(Operation.GETECPOLICIES, new Class[]{});
     PARAMS_DEF.put(Operation.GETECCODECS, new Class[]{});
+    PARAMS_DEF.put(Operation.GETTRASHROOTS, new Class[]{AllUsersParam.class});
     PARAMS_DEF.put(Operation.GET_BLOCK_LOCATIONS, new Class[] {OffsetParam.class, LenParam.class});
   }
 
@@ -765,4 +766,22 @@ public ECPolicyParam() {
       super(NAME, null);
     }
   }
+
+  /**
+   * Class for allusers parameter.
+   */
+  @InterfaceAudience.Private
+  public static class AllUsersParam extends BooleanParam {
+    /**
+     * Parameter name.
+     */
+    public static final String NAME = HttpFSFileSystem.ALLUSERS_PARAM;
+
+    /**
+     * Constructor.
+     */
+    public AllUsersParam() {
+      super(NAME, false);
+    }
+  }
 }

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/server/HttpFSServer.java

@@ -55,6 +55,7 @@
 import org.apache.hadoop.fs.http.server.HttpFSParametersProvider.XAttrNameParam;
 import org.apache.hadoop.fs.http.server.HttpFSParametersProvider.XAttrSetFlagParam;
 import org.apache.hadoop.fs.http.server.HttpFSParametersProvider.XAttrValueParam;
+import org.apache.hadoop.fs.http.server.HttpFSParametersProvider.AllUsersParam;
 import org.apache.hadoop.fs.permission.FsAction;
 import org.apache.hadoop.hdfs.web.JsonUtil;
 import org.apache.hadoop.http.JettyUtils;
@@ -576,6 +577,14 @@ public InputStream run() throws Exception {
       response = Response.ok(js).type(MediaType.APPLICATION_JSON).build();
       break;
     }
+    case GETTRASHROOTS: {
+      Boolean allUsers = params.get(AllUsersParam.NAME, AllUsersParam.class);
+      FSOperations.FSGetTrashRoots command = new FSOperations.FSGetTrashRoots(allUsers);
+      Map json = fsExecute(user, command);
+      AUDIT_LOG.info("allUsers [{}]", allUsers);
+      response = Response.ok(json).type(MediaType.APPLICATION_JSON).build();
+      break;
+    }
     default: {
       throw new IOException(
           MessageFormat.format("Invalid HTTP GET operation [{0}]", op.value()));

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/main/java/org/apache/hadoop/fs/http/server/metrics/HttpFSServerMetrics.java

@@ -67,6 +67,7 @@ public class HttpFSServerMetrics {
   private @Metric MutableCounterLong opsStatus;
   private @Metric MutableCounterLong opsAllECPolicies;
   private @Metric MutableCounterLong opsECCodecs;
+  private @Metric MutableCounterLong opsTrashRoots;
 
   private final MetricsRegistry registry = new MetricsRegistry("httpfsserver");
   private final String name;
@@ -175,4 +176,8 @@ public void incrOpsAllECPolicies() {
   public void incrOpsECCodecs() {
     opsECCodecs.incr();
   }
+
+  public void incrOpsTrashRoots() {
+    opsTrashRoots.incr();
+  }
 }

hadoop-hdfs-project/hadoop-hdfs-httpfs/src/test/java/org/apache/hadoop/fs/http/client/BaseTestHttpFSWith.java

@@ -1219,7 +1219,7 @@ protected enum Operation {
     FILE_STATUS_ATTR, GET_SNAPSHOT_DIFF, GET_SNAPSHOTTABLE_DIRECTORY_LIST,
     GET_SNAPSHOT_LIST, GET_SERVERDEFAULTS, CHECKACCESS, SETECPOLICY,
     SATISFYSTORAGEPOLICY, GET_SNAPSHOT_DIFF_LISTING, GETFILEBLOCKLOCATIONS,
-    GETFILELINKSTATUS, GETSTATUS, GETECPOLICIES, GETECCODECS
+    GETFILELINKSTATUS, GETSTATUS, GETECPOLICIES, GETECCODECS, GETTRASHROOTS
   }
   @SuppressWarnings("methodlength")
   private void operation(Operation op) throws Exception {
@@ -1374,6 +1374,9 @@ private void operation(Operation op) throws Exception {
     case GETECCODECS:
       testGetECCodecs();
       break;
+    case GETTRASHROOTS:
+      testGetTrashRoots();
+      break;
     }
   }
 
@@ -2201,6 +2204,45 @@ private void testGetECCodecs() throws Exception {
     }
   }
 
+  private void testGetTrashRoots() throws Exception {
+    if (isLocalFS()) {
+      // do not test the getAllEEPolicies for local FS.
+      return;
+    }
+    final Path path = new Path("/");
+    FileSystem fs = FileSystem.get(path.toUri(), this.getProxiedFSConf());
+    if (fs instanceof DistributedFileSystem) {
+      DistributedFileSystem dfs =
+          (DistributedFileSystem) FileSystem.get(path.toUri(), this.getProxiedFSConf());
+      FileSystem httpFs = this.getHttpFSFileSystem();
+
+      // Create trash root for user0
+      UserGroupInformation ugi = UserGroupInformation.createRemoteUser("user0");
+      String user0HomeStr = DFSUtilClient.getHomeDirectory(this.getProxiedFSConf(), ugi);
+      Path user0Trash = new Path(user0HomeStr, FileSystem.TRASH_PREFIX);
+      dfs.mkdirs(user0Trash);
+
+      Collection<FileStatus> dfsTrashRoots = dfs.getTrashRoots(true);
+      Collection<FileStatus> diffTrashRoots = null;
+
+      if (httpFs instanceof HttpFSFileSystem) {
+        HttpFSFileSystem httpFS = (HttpFSFileSystem) httpFs;
+        diffTrashRoots = httpFS.getTrashRoots(true);
+      } else if (httpFs instanceof WebHdfsFileSystem) {
+        WebHdfsFileSystem webHdfsFileSystem = (WebHdfsFileSystem) httpFs;
+        diffTrashRoots = webHdfsFileSystem.getTrashRoots(true);
+      } else {
+        Assert.fail(fs.getClass().getSimpleName() +
+            " is not of type HttpFSFileSystem or WebHdfsFileSystem");
+      }
+
+      // Validate getTrashRoots are the same as DistributedFileSystem
+      assertEquals(dfsTrashRoots.size(), diffTrashRoots.size());
+    } else {
+      Assert.fail(fs.getClass().getSimpleName() + " is not of type DistributedFileSystem.");
+    }
+  }
+
   private void assertHttpFsReportListingWithDfsClient(SnapshotDiffReportListing diffReportListing,
       SnapshotDiffReportListing dfsDiffReportListing) {
     Assert.assertEquals(diffReportListing.getCreateList().size(),