001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 package org.apache.oozie.service;
019
020 import org.apache.oozie.service.Service;
021 import org.apache.oozie.service.Services;
022 import org.apache.oozie.util.ParamChecker;
023 import org.apache.hadoop.conf.Configuration;
024
025 import java.io.UnsupportedEncodingException;
026 import java.net.URLDecoder;
027 import java.text.MessageFormat;
028
029 /**
030 * Service that generates and parses callback URLs.
031 */
032 public class CallbackService implements Service {
033
034 public static final String CONF_PREFIX = Service.CONF_PREFIX + "CallbackService.";
035
036 public static final String CONF_BASE_URL = CONF_PREFIX + "base.url";
037
038 private Configuration oozieConf;
039
040 /**
041 * Initialize the service.
042 *
043 * @param services services instance.
044 */
045 public void init(Services services) {
046 oozieConf = services.getConf();
047 }
048
049 /**
050 * Destroy the service.
051 */
052 public void destroy() {
053 }
054
055 /**
056 * Return the public interface of the Dag engine service.
057 *
058 * @return {@link CallbackService}.
059 */
060 public Class<? extends Service> getInterface() {
061 return CallbackService.class;
062 }
063
064 private static final String ID_PARAM = "id=";
065 private static final String STATUS_PARAM = "status=";
066 private static final String CALL_BACK_QUERY_STRING = "{0}?" + ID_PARAM + "{1}" + "&" + STATUS_PARAM + "{2}&";
067
068 /**
069 * Create a callback URL.
070 *
071 * @param actionId action ID for the callback URL.
072 * @param externalStatusVar variable for the caller to inject the external status.
073 * @return the callback URL.
074 */
075 public String createCallBackUrl(String actionId, String externalStatusVar) {
076 ParamChecker.notEmpty(actionId, "actionId");
077 ParamChecker.notEmpty(externalStatusVar, "externalStatusVar");
078 //TODO: figure out why double encoding is happening in case of hadoop callbacks.
079 String baseCallbackUrl = oozieConf.get(CONF_BASE_URL, "http://localhost:8080/oozie/v0/callback");
080 return MessageFormat.format(CALL_BACK_QUERY_STRING, baseCallbackUrl, actionId, externalStatusVar);
081 }
082
083 private String getParam(String str, String name) {
084 String value = null;
085 int start = str.indexOf(name);
086 if (start > -1) {
087 int end = str.indexOf("&", start + 1);
088 start = start + name.length();
089 value = (end > -1) ? str.substring(start, end) : str.substring(start);
090 }
091 return value;
092 }
093
094 /**
095 * Return if a callback URL is valid or not.
096 *
097 * @param callback callback URL (it can be just the callback portion of it).
098 * @return <code>true</code> if the callback URL is valid, <code>false</code> if it is not.
099 */
100 public boolean isValid(String callback) {
101 return callback != null && getParam(callback, ID_PARAM) != null && getParam(callback, STATUS_PARAM) != null;
102 }
103
104 /**
105 * Return the action ID from a callback URL.
106 *
107 * @param callback callback URL (it can be just the callback portion of it).
108 * @return the action ID from a callback URL.
109 */
110 public String getActionId(String callback) {
111 try {
112 return URLDecoder.decode(getParam(ParamChecker.notEmpty(callback, "callback"), ID_PARAM), "UTF-8");
113 }
114 catch (UnsupportedEncodingException ex) {
115 throw new RuntimeException(ex);
116 }
117 }
118
119 /**
120 * Return the action external status from a callback URL.
121 *
122 * @param callback callback URL (it can be just the callback portion of it).
123 * @return the action external status from a callback URL.
124 */
125 public String getExternalStatus(String callback) {
126 try {
127 return URLDecoder.decode(getParam(ParamChecker.notEmpty(callback, "callback"), STATUS_PARAM), "UTF-8");
128 }
129 catch (UnsupportedEncodingException ex) {
130 throw new RuntimeException(ex);
131 }
132 }
133
134 }