HDFS-8448. Create REST Interface for Volumes. Contributed by Anu Engineer.

hadoop-hdfs-project/hadoop-hdfs/CHANGES-HDFS-7240.txt

@@ -10,3 +10,4 @@
     HDFS-8641. OzoneHandler : Add Quota Support. (Anu Engineer via
     Arpit Agarwal)
 
+    HDFS-8448. Create REST Interface for Volumes. (Anu Engineer via cnauroth)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/exceptions/OzoneException.java

@@ -0,0 +1,216 @@
+/*
+ * 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.ozone.web.exceptions;
+
+
+import org.codehaus.jackson.annotate.JsonAutoDetect;
+import org.codehaus.jackson.annotate.JsonProperty;
+import org.codehaus.jackson.map.ObjectMapper;
+
+import java.io.IOException;
+
+/**
+ * Class the represents various errors returned by the
+ * Ozone Layer.
+ */
+public class OzoneException extends Exception {
+
+  @JsonProperty("httpCode")
+  private long httpCode;
+  @JsonProperty("shortMessage")
+  private String shortMessage;
+  @JsonProperty("resource")
+  private String resource;
+  @JsonProperty("message")
+  private String message;
+  @JsonProperty("requestID")
+  private String requestId;
+  @JsonProperty("hostName")
+  private String hostID;
+
+
+  /**
+   * Constructor that allows a shortMessage.
+   *
+   * @param httpCode Error Code
+   * @param shortMessage Short Message
+   */
+  public OzoneException(long httpCode, String shortMessage) {
+    this.shortMessage = shortMessage;
+    this.httpCode = httpCode;
+  }
+
+  /**
+   * Constructor that allows a shortMessage and long message.
+   *
+   * @param httpCode Error Code
+   * @param shortMessage Short Message
+   * @param message long error message
+   */
+  public OzoneException(long httpCode, String shortMessage, String message) {
+    this.shortMessage = shortMessage;
+    this.resource = message;
+    this.httpCode = httpCode;
+  }
+ 
+  /**
+   * Returns the Resource that was involved in the exception.
+   *
+   * @return String
+   */
+  public String getResource() {
+    return resource;
+  }
+
+  /**
+   * Sets Resource.
+   *
+   * @param resourceName - Name of the Resource
+   */
+  public void setResource(String resourceName) {
+    this.resource = resourceName;
+  }
+
+  /**
+   * Gets a detailed message for the error.
+   *
+   * @return String
+   */
+  public String getMessage() {
+    return message;
+  }
+
+  /**
+   * Sets the error message.
+   *
+   * @param longMessage  - Long message
+   */
+  public void setMessage(String longMessage) {
+    this.message = longMessage;
+  }
+
+  /**
+   * Returns request Id.
+   *
+   * @return String
+   */
+  public String getRequestId() {
+    return requestId;
+  }
+
+  /**
+   * Sets request ID.
+   *
+   * @param ozoneRequestId Request ID generated by the Server
+   */
+  public void setRequestId(String ozoneRequestId) {
+    this.requestId = ozoneRequestId;
+  }
+
+  /**
+   * Returns short error string.
+   *
+   * @return String
+   */
+  public String getShortMessage() {
+    return shortMessage;
+  }
+
+  /**
+   * Sets short error string.
+   *
+   * @param shortError Short Error Code
+   */
+  public void setShortMessage(String shortError) {
+    this.shortMessage = shortError;
+  }
+
+  /**
+   * Returns hostID.
+   *
+   * @return String
+   */
+  public String getHostID() {
+    return hostID;
+  }
+
+  /**
+   * Sets host ID.
+   *
+   * @param hostName host Name
+   */
+  public void setHostID(String hostName) {
+    this.hostID = hostName;
+  }
+
+  /**
+   * Returns http error code.
+   *
+   * @return long
+   */
+  public long getHttpCode() {
+    return httpCode;
+  }
+
+  /**
+   * Sets http status.
+   *
+   * @param httpStatus http error code.
+   */
+  public void setHttpCode(long httpStatus) {
+    this.httpCode = httpStatus;
+  }
+
+  /**
+   * Returns a Json String.
+   *
+   * @return JSON representation of the Error
+   */
+  public String toJsonString() {
+    try {
+      ObjectMapper mapper = new ObjectMapper();
+      mapper.setVisibilityChecker(
+          mapper.getSerializationConfig().getDefaultVisibilityChecker()
+              .withCreatorVisibility(JsonAutoDetect.Visibility.NONE)
+              .withFieldVisibility(JsonAutoDetect.Visibility.NONE)
+              .withGetterVisibility(JsonAutoDetect.Visibility.NONE)
+              .withIsGetterVisibility(JsonAutoDetect.Visibility.NONE)
+              .withSetterVisibility(JsonAutoDetect.Visibility.NONE));
+      return mapper.writeValueAsString(this);
+    } catch (IOException ex) {
+      // TODO : Log this error on server side.
+    }
+    // TODO : Replace this with a JSON Object -- That represents this error.
+    return "500 Internal Server Error";
+  }
+
+  /**
+   * Parses an Exception record.
+   *
+   * @param jsonString - Exception in Json format.
+   *
+   * @return OzoneException Object
+   *
+   * @throws IOException
+   */
+  public static OzoneException parse(String jsonString) throws IOException {
+    ObjectMapper mapper = new ObjectMapper();
+    return mapper.readValue(jsonString, OzoneException.class);
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/handlers/UserArgs.java

@@ -0,0 +1,128 @@
+/*
+ * 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.ozone.web.handlers;
+
+import javax.ws.rs.core.HttpHeaders;
+import javax.ws.rs.core.Request;
+import javax.ws.rs.core.UriInfo;
+
+/**
+ * UserArgs is used to package caller info
+ * and pass it down to file system.
+ */
+public class UserArgs {
+  private String userName;
+  private final long requestID;
+  private final String hostName;
+  private final UriInfo uri;
+  private final Request request;
+  private final HttpHeaders headers;
+
+
+  /**
+   * Constructs  user args.
+   *
+   * @param userName - User name
+   * @param requestID _ Request ID
+   * @param hostName - Host Name
+   * @param req  - Request
+   * @param info - Uri Info
+   * @param httpHeaders - http headers
+   */
+  public UserArgs(String userName, long requestID, String hostName, Request req,
+                  UriInfo info, HttpHeaders httpHeaders) {
+    this.hostName = hostName;
+    this.userName = userName;
+    this.requestID = requestID;
+    this.uri = info;
+    this.request = req;
+    this.headers = httpHeaders;
+  }
+
+  /**
+   * Returns hostname.
+   *
+   * @return String
+   */
+  public String getHostName() {
+    return hostName;
+  }
+
+  /**
+   * Returns RequestID.
+   *
+   * @return Long
+   */
+  public long getRequestID() {
+    return requestID;
+  }
+
+  /**
+   * Returns User Name.
+   *
+   * @return String
+   */
+  public String getUserName() {
+    return userName;
+  }
+
+  /**
+   * Sets the user name.
+   *
+   * @param userName Name of the user
+   */
+  public void setUserName(String userName) {
+    this.userName = userName;
+  }
+
+  /**
+   * Returns the resource Name.
+   *
+   * @return String Resource.
+   */
+  public String getResourceName() {
+    return getUserName();
+  }
+
+  /**
+   * Returns Http Headers for this call.
+   *
+   * @return httpHeaders
+   */
+  public HttpHeaders getHeaders() {
+    return headers;
+  }
+
+  /**
+   * Returns Request Object.
+   *
+   * @return Request
+   */
+  public Request getRequest() {
+    return request;
+  }
+
+  /**
+   * Returns UriInfo.
+   *
+   * @return UriInfo
+   */
+  public UriInfo getUri() {
+    return uri;
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/handlers/VolumeArgs.java

@@ -0,0 +1,119 @@
+/*
+ * 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.ozone.web.handlers;
+
+import org.apache.hadoop.ozone.web.request.OzoneQuota;
+
+import javax.ws.rs.core.HttpHeaders;
+import javax.ws.rs.core.Request;
+import javax.ws.rs.core.UriInfo;
+
+/**
+ * VolumeArgs is used to package all volume
+ * related arguments in the call to underlying
+ * file system.
+ */
+public class VolumeArgs extends UserArgs {
+  private String adminName;
+  private final String volumeName;
+  private OzoneQuota quota;
+
+  /**
+   * Returns Quota Information.
+   *
+   * @return Quota
+   */
+  public OzoneQuota getQuota() {
+    return quota;
+  }
+
+  /**
+   * Returns volume name.
+   *
+   * @return String
+   */
+  public String getVolumeName() {
+    return volumeName;
+  }
+
+  /**
+   * Constructs  volume Args.
+   *
+   * @param userName - User name
+   * @param volumeName - volume Name
+   * @param requestID _ Request ID
+   * @param hostName - Host Name
+   * @param request  - Http Request
+   * @param info - URI info
+   * @param headers - http headers
+   */
+  public VolumeArgs(String userName, String volumeName, long requestID,
+                    String hostName, Request request, UriInfo info,
+                    HttpHeaders headers) {
+    super(userName, requestID, hostName, request, info, headers);
+    this.volumeName = volumeName;
+  }
+
+  /**
+   * Sets Quota information.
+   *
+   * @param quota - Quota Sting
+   * @throws IllegalArgumentException
+   */
+  public void setQuota(String quota) throws IllegalArgumentException {
+    this.quota = OzoneQuota.parseQuota(quota);
+  }
+
+  /**
+   * Sets quota information.
+   *
+   * @param quota - OzoneQuota
+   */
+  public void setQuota(OzoneQuota quota) {
+    this.quota = quota;
+  }
+
+  /**
+   * Gets admin Name.
+   *
+   * @return - Admin Name
+   */
+  public String getAdminName() {
+    return adminName;
+  }
+
+  /**
+   * Sets Admin Name.
+   *
+   * @param adminName - Admin Name
+   */
+  public void setAdminName(String adminName) {
+    this.adminName = adminName;
+  }
+
+  /**
+   * Returns UserName/VolumeName.
+   *
+   * @return String
+   */
+  @Override
+  public String getResourceName() {
+    return super.getResourceName() + "/" + getVolumeName();
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/headers/Header.java

@@ -27,6 +27,10 @@ public final class Header {
   public static final String OZONE_QUOTA_GB = "GB";
   public static final String OZONE_QUOTA_TB = "TB";
   public static final String OZONE_QUOTA_REMOVE = "remove";
+  public static final String OZONE_QUOTA_UNDEFINED = "undefined";
+
+  public static final String OZONE_LIST_QUERY_BUCKET ="bucket";
+
   private Header() {
     // Never constructed.
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/interfaces/StorageHandler.java

@@ -0,0 +1,122 @@
+/*
+ * 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.ozone.web.interfaces;
+
+import org.apache.hadoop.ozone.web.exceptions.OzoneException;
+import org.apache.hadoop.ozone.web.handlers.UserArgs;
+import org.apache.hadoop.ozone.web.handlers.VolumeArgs;
+import org.apache.hadoop.ozone.web.response.ListVolumes;
+import org.apache.hadoop.ozone.web.response.VolumeInfo;
+
+import java.io.IOException;
+
+/**
+ * Storage handler Interface is the Interface between
+ * REST protocol and file system.
+ *
+ * We will have two default implementations of this interface.
+ * One for the local file system that is handy while testing
+ * and another which will point to the HDFS backend.
+ */
+public interface StorageHandler {
+
+  /**
+   * Creates a Storage Volume.
+   *
+   * @param args - Volume Name
+   *
+   * @throws IOException
+   * @throws OzoneException
+   */
+  void createVolume(VolumeArgs args) throws IOException, OzoneException;
+
+
+  /**
+   * setVolumeOwner - sets the owner of the volume.
+   *
+   * @param args owner info is present in the args
+   *
+   * @throws IOException
+   * @throws OzoneException
+   */
+  void setVolumeOwner(VolumeArgs args) throws IOException, OzoneException;
+
+
+  /**
+   * Set Volume Quota.
+   *
+   * @param args - Has Quota info
+   * @param remove - true if the request is to remove the quota
+   *
+   * @throws IOException
+   * @throws OzoneException
+   */
+  void setVolumeQuota(VolumeArgs args, boolean remove)
+      throws IOException, OzoneException;
+
+  /**
+   * Checks if a Volume exists and the user specified has access to the
+   * Volume.
+   *
+   * @param args - Volume Args
+   *
+   * @return - Boolean - True if the user can modify the volume.
+   * This is possible for owners of the volume and admin users
+   *
+   * @throws IOException
+   * @throws OzoneException
+   */
+  boolean checkVolumeAccess(VolumeArgs args) throws IOException, OzoneException;
+
+
+  /**
+   * Returns the List of Volumes owned by the specific user.
+   *
+   * @param args - UserArgs
+   *
+   * @return - List of Volumes
+   *
+   * @throws IOException
+   * @throws OzoneException
+   */
+  ListVolumes listVolumes(UserArgs args) throws IOException, OzoneException;
+
+  /**
+   * Deletes an Empty Volume.
+   *
+   * @param args - Volume Args
+   *
+   * @throws IOException
+   * @throws OzoneException
+   */
+  void deleteVolume(VolumeArgs args) throws IOException, OzoneException;
+
+
+  /**
+   * Returns Info about the specified Volume.
+   *
+   * @param args - Volume Args
+   *
+   * @return VolumeInfo
+   *
+   * @throws IOException
+   * @throws OzoneException
+   */
+  VolumeInfo getVolumeInfo(VolumeArgs args) throws IOException, OzoneException;
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/interfaces/Volume.java

@@ -0,0 +1,139 @@
+/*
+ * 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.ozone.web.interfaces;
+
+import org.apache.hadoop.ozone.web.exceptions.OzoneException;
+import org.apache.hadoop.ozone.web.headers.Header;
+
+import javax.ws.rs.DELETE;
+import javax.ws.rs.DefaultValue;
+import javax.ws.rs.GET;
+import javax.ws.rs.POST;
+import javax.ws.rs.PUT;
+import javax.ws.rs.Path;
+import javax.ws.rs.PathParam;
+import javax.ws.rs.QueryParam;
+import javax.ws.rs.core.Context;
+import javax.ws.rs.core.HttpHeaders;
+import javax.ws.rs.core.Request;
+import javax.ws.rs.core.Response;
+import javax.ws.rs.core.UriInfo;
+
+/**
+ * Volume Interface acts as the HTTP entry point for
+ * volume related functionality.
+ */
+@Path("/{volume}")
+public interface Volume {
+
+  /**
+   * Creates a Volume owned by the user.
+   *
+   * Params :
+   * Quota - Specifies the Maximum usable size by the user
+   * the valid parameters for quota are <int>(<BYTES| MB|GB|TB>) | remove.
+   * For example 10GB or "remove".
+   *
+   * @param volume Volume Name, this has to be unique at Ozone Level
+   * @param quota Quota for this Storage Volume - <int>(<MB|GB|TB>) | remove
+   * @param req - Request Object - Request Object
+   * @param uriInfo - Http UriInfo
+   * @param headers Http Headers HttpHeaders
+   *
+   * @return Response
+   *
+   * @throws OzoneException
+   */
+
+  @POST
+  Response createVolume(@PathParam("volume") String volume,
+                        @DefaultValue(Header.OZONE_QUOTA_UNDEFINED)
+                        @QueryParam("quota") String quota,
+                        @Context Request req,
+                        @Context UriInfo uriInfo,
+                        @Context HttpHeaders headers)
+    throws OzoneException;
+
+
+  /**
+   * Updates a Volume owned by the user.
+   *
+   * Params :
+   * Owner - Specifies the name of the owner
+   * Quota - Specifies the Maximum usable size by the user
+   * the valid parameters for quota are <int>(<MB|GB|TB>) | remove.
+   * For example 10GB or "remove".
+   *
+   * @param volume Volume Name, this has to be unique at Ozone Level
+   * @param quota Quota for this Storage Volume - <int>(<MB|GB|TB>) | remove
+   * @param req - Request Object - Request Object
+   * @param headers Http Headers HttpHeaders
+   *
+   * @return Response
+   *
+   * @throws OzoneException
+   */
+  @PUT
+  Response updateVolume(@PathParam("volume") String volume,
+                        @DefaultValue(Header.OZONE_QUOTA_UNDEFINED)
+                        @QueryParam("quota") String quota,
+                        @Context Request req,
+                        @Context UriInfo uriInfo,
+                        @Context HttpHeaders headers)
+    throws OzoneException;
+
+
+  /**
+   * Deletes a Volume if it is empty.
+   *
+   * @param volume Storage Volume Name
+   *
+   * @return Response Response
+   *
+   * @throws OzoneException
+   */
+  @DELETE
+  Response deleteVolume(@PathParam("volume") String volume,
+                        @Context Request req,
+                        @Context UriInfo uriInfo,
+                        @Context HttpHeaders headers)
+    throws OzoneException;
+
+  /**
+   * Returns Volume info. This API can be invoked either
+   * by admin or the owner
+   *
+   * @param volume - Storage Volume Name
+   * @param req - Http Req
+   * @param headers - Http headers
+   *
+   * @return - Response
+   *
+   * @throws OzoneException
+   */
+  @GET
+  Response getVolumeInfo(@PathParam("volume") String volume,
+                         @DefaultValue(Header.OZONE_LIST_QUERY_BUCKET)
+                         @QueryParam("info") String info,
+                         @Context Request req,
+                         @Context UriInfo uriInfo,
+                         @Context HttpHeaders headers)
+    throws OzoneException;
+
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/response/ListVolumes.java

@@ -0,0 +1,143 @@
+/*
+ * 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.ozone.web.response;
+
+import org.codehaus.jackson.annotate.JsonAutoDetect;
+import org.codehaus.jackson.annotate.JsonMethod;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.map.ObjectWriter;
+import org.codehaus.jackson.map.annotate.JsonFilter;
+import org.codehaus.jackson.map.ser.FilterProvider;
+import org.codehaus.jackson.map.ser.impl.SimpleBeanPropertyFilter;
+import org.codehaus.jackson.map.ser.impl.SimpleFilterProvider;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+
+/**
+ * List Volume Class is the class that is returned in JSON format to
+ * users when they call ListVolumes.
+ */
+public class ListVolumes {
+  private List<VolumeInfo> volumes;
+
+  static final String VOLUME_LIST = "VOLUME_LIST_FILTER";
+
+  /**
+   * Used for json filtering.
+   */
+  @JsonFilter(VOLUME_LIST)
+  class MixIn {
+  }
+
+  /**
+   * Constructs ListVolume objects.
+   */
+  public ListVolumes() {
+    this.volumes = new LinkedList<VolumeInfo>();
+  }
+
+  /**
+   * Gets the list of volumes.
+   *
+   * @return List of VolumeInfo Objects
+   */
+  public List<VolumeInfo> getVolumes() {
+    return volumes;
+  }
+
+
+  /**
+   * Sets volume info.
+   *
+   * @param volumes - List of Volumes
+   */
+  public void setVolumes(List<VolumeInfo> volumes) {
+    this.volumes = volumes;
+  }
+
+  /**
+   * Returns a JSON string of this object.
+   * After stripping out bytesUsed and bucketCount
+   *
+   * @return String
+   */
+  public String toJsonString() throws IOException {
+    ObjectMapper mapper = new ObjectMapper();
+    String[] ignorableFieldNames = {"bytesUsed", "bucketCount"};
+
+    FilterProvider filters = new SimpleFilterProvider()
+        .addFilter(VOLUME_LIST,
+            SimpleBeanPropertyFilter.serializeAllExcept(ignorableFieldNames));
+
+    mapper.setVisibility(JsonMethod.FIELD, JsonAutoDetect.Visibility.ANY);
+    mapper.getSerializationConfig()
+        .addMixInAnnotations(Object.class, MixIn.class);
+    ObjectWriter writer = mapper.writer(filters);
+
+    return writer.writeValueAsString(this);
+  }
+
+  /**
+   * When we serialize a volumeInfo to our database
+   * we will use all fields. However the toJsonString
+   * will strip out bytesUsed and bucketCount from the
+   * volume Info
+   *
+   * @return Json String
+   *
+   * @throws IOException
+   */
+  public String toDBString() throws IOException {
+    ObjectMapper mapper = new ObjectMapper();
+    return mapper.writeValueAsString(this);
+  }
+
+  /**
+   * Parses a String to return ListVolumes object.
+   *
+   * @param data - Json String
+   *
+   * @return - ListVolumes
+   *
+   * @throws IOException
+   */
+  public static ListVolumes parse(String data) throws IOException {
+    ObjectMapper mapper = new ObjectMapper();
+    return mapper.readValue(data, ListVolumes.class);
+  }
+
+  /**
+   * Adds a new volume info to the List.
+   *
+   * @param info - VolumeInfo
+   */
+  public void addVolume(VolumeInfo info) {
+    this.volumes.add(info);
+  }
+
+  /**
+   * Sorts the volume names based on volume name.
+   * This is useful when we return the list of volume names
+   */
+  public void sort() {
+    Collections.sort(volumes);
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/response/VolumeInfo.java

@@ -0,0 +1,299 @@
+/*
+ * 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.ozone.web.response;
+
+
+import org.apache.hadoop.ozone.web.request.OzoneQuota;
+import org.codehaus.jackson.annotate.JsonAutoDetect;
+import org.codehaus.jackson.annotate.JsonMethod;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.map.ObjectWriter;
+import org.codehaus.jackson.map.annotate.JsonFilter;
+import org.codehaus.jackson.map.ser.FilterProvider;
+import org.codehaus.jackson.map.ser.impl.SimpleBeanPropertyFilter;
+import org.codehaus.jackson.map.ser.impl.SimpleFilterProvider;
+
+import java.io.IOException;
+
+/**
+ * VolumeInfo Class is the Java class that represents
+ * Json when VolumeInfo Call is made.
+ */
+public class VolumeInfo implements Comparable<VolumeInfo> {
+
+  static final String VOLUME_INFO = "VOLUME_INFO_FILTER";
+
+  /**
+   * Custom Json Filter Class.
+   */
+  @JsonFilter(VOLUME_INFO)
+  class MixIn {
+  }
+  private VolumeOwner owner;
+  private OzoneQuota quota;
+  private String volumeName;
+  private String createdOn;
+  private String createdBy;
+
+  private long bytesUsed;
+  private long bucketCount;
+
+
+  /**
+   * Constructor for VolumeInfo.
+   *
+   * @param volumeName - Name of the Volume
+   * @param createdOn _ Date String
+   * @param createdBy - Person who created it
+   */
+  public VolumeInfo(String volumeName, String createdOn, String createdBy) {
+    this.createdOn = createdOn;
+    this.volumeName = volumeName;
+    this.createdBy = createdBy;
+  }
+
+  /**
+   * Constructor for VolumeInfo.
+   */
+  public VolumeInfo() {
+  }
+
+  /**
+   * Returns the name of the person who created this volume.
+   *
+   * @return Name of Admin who created this
+   */
+  public String getCreatedBy() {
+    return createdBy;
+  }
+
+  /**
+   * Sets the user name of the person who created this volume.
+   *
+   * @param createdBy - UserName
+   */
+  public void setCreatedBy(String createdBy) {
+    this.createdBy = createdBy;
+  }
+
+  /**
+   * Gets the date on which this volume was created.
+   *
+   * @return - Date String
+   */
+  public String getCreatedOn() {
+    return createdOn;
+  }
+
+  /**
+   * Sets the date string.
+   *
+   * @param createdOn - Date String
+   */
+  public void setCreatedOn(String createdOn) {
+    this.createdOn = createdOn;
+  }
+
+  /**
+   * Returns the owner info.
+   *
+   * @return - OwnerInfo
+   */
+  public VolumeOwner getOwner() {
+    return owner;
+  }
+
+  /**
+   * Sets the owner.
+   *
+   * @param owner - OwnerInfo
+   */
+  public void setOwner(VolumeOwner owner) {
+    this.owner = owner;
+  }
+
+  /**
+   * Returns the quota information on a volume.
+   *
+   * @return Quota
+   */
+  public OzoneQuota getQuota() {
+    return quota;
+  }
+
+  /**
+   * Sets the quota info.
+   *
+   * @param quota - Quota Info
+   */
+  public void setQuota(OzoneQuota quota) {
+    this.quota = quota;
+  }
+
+  /**
+   * gets the volume name.
+   *
+   * @return - Volume Name
+   */
+  public String getVolumeName() {
+    return volumeName;
+  }
+
+  /**
+   * Sets the volume name.
+   *
+   * @param volumeName - Volume Name
+   */
+  public void setVolumeName(String volumeName) {
+    this.volumeName = volumeName;
+  }
+
+  /**
+   * Returns a JSON string of this object.
+   * After stripping out bytesUsed and bucketCount
+   *
+   * @return String - json string
+   * @throws IOException
+   */
+  public String toJsonString() throws IOException {
+    ObjectMapper mapper = new ObjectMapper();
+    String[] ignorableFieldNames = {"bytesUsed", "bucketCount"};
+
+    FilterProvider filters = new SimpleFilterProvider()
+        .addFilter(VOLUME_INFO, SimpleBeanPropertyFilter
+            .serializeAllExcept(ignorableFieldNames));
+
+    mapper.setVisibility(JsonMethod.FIELD, JsonAutoDetect.Visibility.ANY);
+    mapper.getSerializationConfig()
+        .addMixInAnnotations(Object.class, MixIn.class);
+    ObjectWriter writer = mapper.writer(filters);
+
+    return writer.writeValueAsString(this);
+  }
+
+  /**
+   * When we serialize a volumeInfo to our database
+   * we will use all fields. However the toJsonString
+   * will strip out bytesUsed and bucketCount from the
+   * volume Info
+   *
+   * @return Json String
+   *
+   * @throws IOException
+   */
+  public String toDBString() throws IOException {
+    ObjectMapper mapper = new ObjectMapper();
+    return mapper.writeValueAsString(this);
+  }
+
+
+  /**
+   * Comparable Interface.
+   * @param o VolumeInfo Object.
+   * @return Result of comparison
+   */
+  @Override
+  public int compareTo(VolumeInfo o) {
+    return this.volumeName.compareTo(o.getVolumeName());
+  }
+
+  /**
+   * Gets the number of bytesUsed by this volume.
+   *
+   * @return long - Bytes used
+   */
+  public long getBytesUsed() {
+    return bytesUsed;
+  }
+
+  /**
+   * Sets number of bytesUsed by this volume.
+   *
+   * @param bytesUsed - Number of bytesUsed
+   */
+  public void setBytesUsed(long bytesUsed) {
+    this.bytesUsed = bytesUsed;
+  }
+
+  /**
+   * Returns VolumeInfo class from json string.
+   *
+   * @param data - Json String
+   *
+   * @return VolumeInfo
+   *
+   * @throws IOException
+   */
+  public static VolumeInfo parse(String data) throws IOException {
+    ObjectMapper mapper = new ObjectMapper();
+    return mapper.readValue(data, VolumeInfo.class);
+  }
+
+  /**
+   * Indicates whether some other object is "equal to" this one.
+   *
+   * @param obj the reference object with which to compare.
+   *
+   * @return {@code true} if this object is the same as the obj
+   * argument; {@code false} otherwise.
+   */
+  @Override
+  public boolean equals(Object obj) {
+    if (obj == null) {
+      return false;
+    }
+    if (getClass() != obj.getClass()) {
+      return false;
+    }
+    VolumeInfo otherInfo = (VolumeInfo) obj;
+    return otherInfo.getVolumeName().equals(this.getVolumeName());
+  }
+
+  /**
+   * Returns a hash code value for the object. This method is
+   * supported for the benefit of hash tables such as those provided by
+   * HashMap.
+   * @return a hash code value for this object.
+   *
+   * @see Object#equals(Object)
+   * @see System#identityHashCode
+   */
+  @Override
+  public int hashCode() {
+    return getVolumeName().hashCode();
+  }
+
+  /**
+   * Total number of buckets under this volume.
+   *
+   * @return - bucketCount
+   */
+  public long getBucketCount() {
+    return bucketCount;
+  }
+
+  /**
+   * Sets the buckets count.
+   *
+   * @param bucketCount - Bucket Count
+   */
+  public void setBucketCount(long bucketCount) {
+    this.bucketCount = bucketCount;
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/web/response/VolumeOwner.java

@@ -0,0 +1,59 @@
+/*
+ * 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.ozone.web.response;
+
+
+import org.codehaus.jackson.map.annotate.JsonSerialize;
+
+/**
+ * Volume Owner represents the owner of a volume.
+ *
+ * This is a class instead of a string since we might need to extend this class
+ * to support other forms of authentication.
+ */
+public class VolumeOwner {
+  @JsonSerialize(include=JsonSerialize.Inclusion.NON_NULL)
+  private String name;
+
+  /**
+   * Constructor for VolumeOwner.
+   *
+   * @param name - name of the User
+   */
+  public VolumeOwner(String name) {
+    this.name = name;
+  }
+
+  /**
+   * Constructs Volume Owner.
+   */
+  public VolumeOwner() {
+    name = null;
+  }
+
+  /**
+   * Returns the user name.
+   *
+   * @return Name
+   */
+  public String getName() {
+    return name;
+  }
+
+}