Java tutorial
/** * 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.falcon.resource; import org.apache.commons.lang3.StringUtils; import org.apache.falcon.FalconException; import org.apache.falcon.FalconWebException; import org.apache.falcon.entity.EntityNotRegisteredException; import org.apache.falcon.entity.EntityUtil; import org.apache.falcon.entity.parser.ValidationException; import org.apache.falcon.extensions.ExtensionStatus; import org.apache.falcon.entity.v0.EntityType; import org.apache.falcon.extensions.jdbc.ExtensionMetaStore; import org.apache.falcon.extensions.store.ExtensionStore; import org.apache.falcon.persistence.ExtensionBean; import org.apache.falcon.persistence.ExtensionJobsBean; import org.apache.falcon.security.CurrentUser; import org.codehaus.jettison.json.JSONArray; import org.codehaus.jettison.json.JSONException; import org.codehaus.jettison.json.JSONObject; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.ws.rs.core.Response; import java.util.Collections; import java.util.List; import java.util.SortedMap; import java.util.TreeMap; /** * A base class for managing Extension Operations. */ public class AbstractExtensionManager extends AbstractSchedulableEntityManager { public static final Logger LOG = LoggerFactory.getLogger(AbstractExtensionManager.class); private static final String JOB_NAME = "jobName"; protected static final String TAG_PREFIX_EXTENSION_JOB = "_falcon_extension_job="; private static final String EXTENSION_NAME = "extensionName"; private static final String FEEDS = "feeds"; private static final String PROCESSES = "processes"; private static final String CONFIG = "config"; private static final String CREATION_TIME = "creationTime"; private static final String LAST_UPDATE_TIME = "lastUpdatedTime"; protected static final String ASCENDING_SORT_ORDER = "asc"; protected static final String DESCENDING_SORT_ORDER = "desc"; public static final String NAME = "name"; public static final String STATUS = "status"; private static final String EXTENSION_TYPE = "type"; private static final String EXTENSION_DESC = "description"; private static final String EXTENSION_LOCATION = "location"; private static final String ENTITY_EXISTS_STATUS = "EXISTS"; private static final String ENTITY_NOT_EXISTS_STATUS = "NOT_EXISTS"; protected static void validateExtensionName(final String extensionName) { if (StringUtils.isBlank(extensionName)) { throw FalconWebException.newAPIException("Extension name is mandatory and shouldn't be blank", Response.Status.BAD_REQUEST); } } protected APIResult registerExtensionMetadata(String extensionName, String path, String description, String owner) { validateExtensionName(extensionName); try { return new APIResult(APIResult.Status.SUCCEEDED, ExtensionStore.get().registerExtension(extensionName, path, description, owner)); } catch (Throwable e) { throw FalconWebException.newAPIException(e, Response.Status.INTERNAL_SERVER_ERROR); } } public APIResult getExtensionJobDetail(String jobName) { try { return new APIResult(APIResult.Status.SUCCEEDED, buildExtensionJobDetailResult(jobName).toString()); } catch (FalconException e) { throw FalconWebException.newAPIException(e, Response.Status.INTERNAL_SERVER_ERROR); } } protected APIResult getExtensionDetail(String extensionName) { try { return new APIResult(APIResult.Status.SUCCEEDED, buildExtensionDetailResult(extensionName).toString()); } catch (FalconException e) { throw FalconWebException.newAPIException(e, Response.Status.INTERNAL_SERVER_ERROR); } } public APIResult getExtensions() { try { return new APIResult(APIResult.Status.SUCCEEDED, buildEnumerateResult().toString()); } catch (FalconException e) { throw FalconWebException.newAPIException(e, Response.Status.INTERNAL_SERVER_ERROR); } } public ExtensionJobList getExtensionJobs(String extensionName, String sortOrder, String doAsUser) { TreeMap<String, String> jobAndExtensionNames = new TreeMap<>(); List<ExtensionJobsBean> extensionJobs = null; if (StringUtils.isNoneBlank(extensionName)) { extensionJobs = ExtensionStore.getMetaStore().getJobsForAnExtension(extensionName); } else { extensionJobs = ExtensionStore.getMetaStore().getAllExtensionJobs(); } for (ExtensionJobsBean job : extensionJobs) { jobAndExtensionNames.put(job.getJobName(), job.getExtensionName()); } sortOrder = (sortOrder == null) ? ASCENDING_SORT_ORDER : sortOrder; switch (sortOrder.toLowerCase()) { case DESCENDING_SORT_ORDER: return new ExtensionJobList(extensionJobs.size(), jobAndExtensionNames.descendingMap()); default: return new ExtensionJobList(extensionJobs.size(), jobAndExtensionNames); } } public APIResult deleteExtensionMetadata(String extensionName) { validateExtensionName(extensionName); ExtensionStore metaStore = ExtensionStore.get(); try { canDeleteExtension(extensionName); return new APIResult(APIResult.Status.SUCCEEDED, metaStore.deleteExtension(extensionName, CurrentUser.getUser())); } catch (FalconException e) { throw FalconWebException.newAPIException(e); } } private void canDeleteExtension(String extensionName) throws FalconException { ExtensionMetaStore metaStore = ExtensionStore.getMetaStore(); List<ExtensionJobsBean> extensionJobs = metaStore.getJobsForAnExtension(extensionName); if (!extensionJobs.isEmpty()) { StringBuilder jobs = new StringBuilder(); for (ExtensionJobsBean extensionJobsBean : extensionJobs) { jobs.append("\n" + extensionJobsBean.getJobName()); } LOG.error("Extension:" + extensionName + " cannot be unregistered as following instances are dependent on " + "the extension:" + jobs.toString()); throw new FalconException( "Extension:" + extensionName + " cannot be unregistered as following instances" + " are dependent on the extension:" + jobs.toString()); } } protected SortedMap<EntityType, List<String>> getJobEntities(ExtensionJobsBean extensionJobsBean) throws FalconException { TreeMap<EntityType, List<String>> entityMap = new TreeMap<>(Collections.<EntityType>reverseOrder()); entityMap.put(EntityType.PROCESS, extensionJobsBean.getProcesses()); entityMap.put(EntityType.FEED, extensionJobsBean.getFeeds()); return entityMap; } private JSONObject buildExtensionJobDetailResult(final String jobName) throws FalconException { ExtensionMetaStore metaStore = ExtensionStore.getMetaStore(); ExtensionJobsBean jobsBean = metaStore.getExtensionJobDetails(jobName); if (jobsBean == null) { throw new ValidationException("Job name not found:" + jobName); } ExtensionBean extensionBean = metaStore.getDetail(jobsBean.getExtensionName()); JSONObject detailsObject = new JSONObject(); try { detailsObject.put(JOB_NAME, jobsBean.getJobName()); detailsObject.put(EXTENSION_NAME, jobsBean.getExtensionName()); detailsObject.put(FEEDS, getEntitiesStatus(jobsBean.getFeeds(), EntityType.FEED)); detailsObject.put(PROCESSES, getEntitiesStatus(jobsBean.getProcesses(), EntityType.PROCESS)); detailsObject.put(CONFIG, jobsBean.getConfig()); detailsObject.put(CREATION_TIME, jobsBean.getCreationTime()); detailsObject.put(LAST_UPDATE_TIME, jobsBean.getLastUpdatedTime()); detailsObject.put(EXTENSION_LOCATION, extensionBean.getLocation()); detailsObject.put(EXTENSION_TYPE, extensionBean.getExtensionType()); } catch (JSONException e) { LOG.error("Exception while building extension jon details for job {}", jobName, e); } return detailsObject; } public static String getJobNameFromTag(String tags) { int nameStart = tags.indexOf(TAG_PREFIX_EXTENSION_JOB); if (nameStart == -1) { return null; } nameStart = nameStart + TAG_PREFIX_EXTENSION_JOB.length(); int nameEnd = tags.indexOf(',', nameStart); if (nameEnd == -1) { nameEnd = tags.length(); } return tags.substring(nameStart, nameEnd); } protected String disableExtension(String extensionName, String currentUser) { validateExtensionName(extensionName); try { return ExtensionStore.get().updateExtensionStatus(extensionName, currentUser, ExtensionStatus.DISABLED); } catch (Throwable e) { throw FalconWebException.newAPIException(e, Response.Status.INTERNAL_SERVER_ERROR); } } protected String enableExtension(String extensionName, String currentUser) { validateExtensionName(extensionName); try { return ExtensionStore.get().updateExtensionStatus(extensionName, currentUser, ExtensionStatus.ENABLED); } catch (Throwable e) { throw FalconWebException.newAPIException(e, Response.Status.INTERNAL_SERVER_ERROR); } } private JSONObject buildExtensionDetailResult(final String extensionName) throws FalconException { ExtensionMetaStore metaStore = ExtensionStore.getMetaStore(); if (!metaStore.checkIfExtensionExists(extensionName)) { throw new ValidationException("No extension resources found for " + extensionName); } ExtensionBean extensionBean = metaStore.getDetail(extensionName); if (extensionBean == null) { LOG.error("Extension not found: " + extensionName); throw new FalconException("Extension not found:" + extensionName); } JSONObject resultObject = new JSONObject(); try { resultObject.put(NAME, extensionBean.getExtensionName()); resultObject.put(EXTENSION_TYPE, extensionBean.getExtensionType()); resultObject.put(EXTENSION_DESC, extensionBean.getDescription()); resultObject.put(EXTENSION_LOCATION, extensionBean.getLocation()); } catch (JSONException e) { LOG.error("Exception in buildDetailResults:", e); throw new FalconException(e); } return resultObject; } private static JSONArray buildEnumerateResult() throws FalconException { JSONArray results = new JSONArray(); ExtensionMetaStore metaStore = ExtensionStore.getMetaStore(); List<ExtensionBean> extensionBeanList = metaStore.getAllExtensions(); for (ExtensionBean extensionBean : extensionBeanList) { JSONObject resultObject = new JSONObject(); try { resultObject.put(NAME, extensionBean.getExtensionName().toLowerCase()); resultObject.put(EXTENSION_TYPE, extensionBean.getExtensionType()); resultObject.put(EXTENSION_DESC, extensionBean.getDescription()); resultObject.put(EXTENSION_LOCATION, extensionBean.getLocation()); } catch (JSONException e) { throw new FalconException(e); } results.put(resultObject); } return results; } protected static void checkIfExtensionIsEnabled(String extensionName) { ExtensionBean extensionBean = getExtensionIfExists(extensionName); if (!extensionBean.getStatus().equals(ExtensionStatus.ENABLED)) { LOG.error("Extension: " + extensionName + " is in disabled state."); throw FalconWebException.newAPIException("Extension: " + extensionName + " is in disabled state.", Response.Status.INTERNAL_SERVER_ERROR); } } protected static ExtensionBean getExtensionIfExists(String extensionName) { ExtensionMetaStore metaStore = ExtensionStore.getMetaStore(); ExtensionBean extensionBean = metaStore.getDetail(extensionName); if (extensionBean == null) { LOG.error("Extension not found: " + extensionName); throw FalconWebException.newAPIException("Extension not found:" + extensionName, Response.Status.NOT_FOUND); } return extensionBean; } protected static void checkIfExtensionJobNameExists(String jobName, String extensionName) { ExtensionMetaStore metaStore = ExtensionStore.getMetaStore(); ExtensionJobsBean extensionJobsBean = metaStore.getExtensionJobDetails(jobName); if (extensionJobsBean != null && !extensionJobsBean.getExtensionName().equals(extensionName)) { LOG.error("Extension job with name: " + extensionName + " already exists."); throw FalconWebException.newAPIException("Extension job with name: " + jobName + " already exists.", Response.Status.INTERNAL_SERVER_ERROR); } } private JSONArray getEntitiesStatus(List<String> entities, EntityType type) throws JSONException, FalconException { JSONArray entityObjects = new JSONArray(); for (String entity : entities) { JSONObject entityObject = new JSONObject(); try { entityObject.put(NAME, entity); EntityUtil.getEntity(type, entity); entityObject.put(STATUS, ENTITY_EXISTS_STATUS); } catch (EntityNotRegisteredException e) { entityObject.put(STATUS, ENTITY_NOT_EXISTS_STATUS); } entityObjects.put(entityObject); } return entityObjects; } }