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.ambari.view.slider.rest.client; import java.io.IOException; import java.io.StringReader; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Map.Entry; import org.apache.ambari.view.slider.clients.AmbariClient; import org.apache.ambari.view.slider.clients.AmbariCluster; import org.apache.ambari.view.slider.clients.AmbariClusterInfo; import org.apache.ambari.view.slider.clients.AmbariHostComponent; import org.apache.ambari.view.slider.clients.AmbariHostInfo; import org.apache.ambari.view.slider.clients.AmbariService; import org.apache.ambari.view.slider.clients.AmbariServiceInfo; import org.apache.commons.httpclient.HttpException; import org.apache.commons.httpclient.HttpStatus; import org.apache.log4j.Logger; import com.google.gson.JsonArray; import com.google.gson.JsonElement; import com.google.gson.JsonObject; import com.google.gson.JsonParser; import com.google.gson.stream.JsonReader; public class AmbariHttpClient extends BaseHttpClient implements AmbariClient { private static final Logger logger = Logger.getLogger(AmbariHttpClient.class); public AmbariHttpClient(String url, String userId, String password) { super(url, userId, password); } @SuppressWarnings("deprecation") private RuntimeException createRuntimeException(HttpException httpException) { String message = httpException.getMessage(); try { JsonElement jsonElement = new JsonParser() .parse(new JsonReader(new StringReader(httpException.getMessage()))); if (jsonElement != null && jsonElement.getAsJsonObject().has("message")) { message = jsonElement.getAsJsonObject().get("message").getAsString(); } } catch (Throwable t) { } if (httpException.getReasonCode() != HttpStatus.SC_OK) { message = httpException.getReasonCode() + " " + httpException.getReason() + ": " + message; } return new RuntimeException(message, httpException); } /** * Provides the first cluster defined on this Ambari server. * * @return */ public AmbariClusterInfo getClusterInfo() { try { JsonElement jsonElement = doGetJson("/api/v1/clusters"); if (jsonElement == null) { return null; } JsonObject jsonObject = jsonElement.getAsJsonObject(); JsonArray clustersArray = jsonObject.get("items").getAsJsonArray(); if (clustersArray.size() > 0) { AmbariClusterInfo cluster = new AmbariClusterInfo(); JsonObject clusterObj = clustersArray.get(0).getAsJsonObject().get("Clusters").getAsJsonObject(); cluster.setName(clusterObj.get("cluster_name").getAsString()); cluster.setVersion(clusterObj.get("version").getAsString()); return cluster; } } catch (HttpException e) { logger.warn("Unable to determine Ambari clusters", e); throw createRuntimeException(e); } catch (IOException e) { logger.warn("Unable to determine Ambari clusters", e); throw new RuntimeException(e.getMessage(), e); } return null; } /** * Provides the first cluster defined on this Ambari server. * * @return */ public Map<String, String> getAmbariServerConfigs() { Map<String, String> configs = new HashMap<String, String>(); try { JsonElement jsonElement = doGetJson("/api/v1/services/AMBARI/components/AMBARI_SERVER"); if (jsonElement != null && jsonElement.getAsJsonObject().has("RootServiceComponents") && jsonElement .getAsJsonObject().get("RootServiceComponents").getAsJsonObject().has("properties")) { JsonObject ambariProperties = jsonElement.getAsJsonObject().get("RootServiceComponents") .getAsJsonObject().get("properties").getAsJsonObject(); for (Entry<String, JsonElement> entry : ambariProperties.entrySet()) { if (entry.getValue().isJsonPrimitive()) { configs.put(entry.getKey(), entry.getValue().getAsString()); } } } } catch (HttpException e) { logger.warn("Unable to determine Ambari clusters", e); } catch (IOException e) { logger.warn("Unable to determine Ambari clusters", e); } return configs; } public AmbariCluster getCluster(AmbariClusterInfo clusterInfo) { if (clusterInfo != null) { try { JsonElement jsonElement = doGetJson("/api/v1/clusters/" + clusterInfo.getName() + "?fields=services/ServiceInfo,hosts,Clusters"); if (jsonElement != null) { AmbariCluster cluster = new AmbariCluster(); // desired configs Map<String, String> desiredConfigs = new HashMap<String, String>(); JsonObject jsonObject = jsonElement.getAsJsonObject(); JsonObject clustersJsonObject = jsonObject.get("Clusters").getAsJsonObject(); JsonObject desiredConfigsObj = clustersJsonObject.get("desired_configs").getAsJsonObject(); for (Map.Entry<String, JsonElement> entry : desiredConfigsObj.entrySet()) { desiredConfigs.put(entry.getKey(), entry.getValue().getAsJsonObject().get("tag").getAsString()); } cluster.setDesiredConfigs(desiredConfigs); cluster.setName(clustersJsonObject.get("cluster_name").getAsString()); cluster.setVersion(clustersJsonObject.get("version").getAsString()); // services List<AmbariServiceInfo> services = new ArrayList<AmbariServiceInfo>(); for (JsonElement svcJson : jsonObject.get("services").getAsJsonArray()) { AmbariServiceInfo si = new AmbariServiceInfo(); si.setId(svcJson.getAsJsonObject().get("ServiceInfo").getAsJsonObject().get("service_name") .getAsString()); si.setStarted("STARTED".equals(svcJson.getAsJsonObject().get("ServiceInfo") .getAsJsonObject().get("state").getAsString())); services.add(si); } cluster.setServices(services); // hosts List<AmbariHostInfo> hosts = new ArrayList<AmbariHostInfo>(); for (JsonElement hostJson : jsonObject.get("hosts").getAsJsonArray()) { AmbariHostInfo hi = new AmbariHostInfo(); hi.setHostName(hostJson.getAsJsonObject().get("Hosts").getAsJsonObject().get("host_name") .getAsString()); hosts.add(hi); } cluster.setHosts(hosts); return cluster; } } catch (IllegalStateException e) { logger.warn("Unable to determine Ambari cluster details - " + clusterInfo.getName(), e); throw new RuntimeException(e.getMessage(), e); } catch (HttpException e) { logger.warn("Unable to determine Ambari cluster details - " + clusterInfo.getName(), e); throw createRuntimeException(e); } catch (IOException e) { logger.warn("Unable to determine Ambari cluster details - " + clusterInfo.getName(), e); throw new RuntimeException(e.getMessage(), e); } } return null; } public Map<String, String> getConfiguration(AmbariClusterInfo cluster, String configType, String configTag) { if (cluster != null && configType != null && configTag != null) { try { JsonElement jsonElement = doGetJson("/api/v1/clusters/" + cluster.getName() + "/configurations?type=" + configType + "&tag=" + configTag); if (jsonElement != null) { JsonObject jsonObject = jsonElement.getAsJsonObject(); JsonArray configsArray = jsonObject.get("items").getAsJsonArray(); if (configsArray.size() > 0) { JsonObject propertiesObj = configsArray.get(0).getAsJsonObject().get("properties") .getAsJsonObject(); Map<String, String> properties = new HashMap<String, String>(); for (Map.Entry<String, JsonElement> entry : propertiesObj.entrySet()) { if (entry.getValue().isJsonPrimitive()) { properties.put(entry.getKey(), entry.getValue().getAsString()); } } return properties; } } } catch (HttpException e) { logger.warn("Unable to determine Ambari clusters", e); throw createRuntimeException(e); } catch (IOException e) { logger.warn("Unable to determine Ambari clusters", e); throw new RuntimeException(e.getMessage(), e); } } return null; } @Override public AmbariService getService(AmbariClusterInfo cluster, String serviceId) { if (cluster != null && serviceId != null) { try { JsonElement jsonElement = doGetJson("/api/v1/clusters/" + cluster.getName() + "/services/" + serviceId + "?fields=ServiceInfo,components/host_components/HostRoles"); if (jsonElement == null) { return null; } JsonObject jsonObject = jsonElement.getAsJsonObject(); AmbariService svc = new AmbariService(); JsonObject serviceInfoJsonObject = jsonObject.get("ServiceInfo").getAsJsonObject(); svc.setId(serviceInfoJsonObject.get("service_name").getAsString()); svc.setStarted("STARTED".equals(serviceInfoJsonObject.get("state").getAsString())); svc.setMaintenanceMode(!"OFF".equals(serviceInfoJsonObject.get("maintenance_state").getAsString())); Map<String, List<AmbariHostComponent>> componentsToHostComponentsMap = new HashMap<String, List<AmbariHostComponent>>(); for (JsonElement ce : jsonObject.get("components").getAsJsonArray()) { String componentName = ce.getAsJsonObject().get("ServiceComponentInfo").getAsJsonObject() .get("component_name").getAsString(); List<AmbariHostComponent> hcList = new ArrayList<AmbariHostComponent>(); componentsToHostComponentsMap.put(componentName, hcList); JsonArray hcJsonArray = ce.getAsJsonObject().get("host_components").getAsJsonArray(); for (JsonElement hce : hcJsonArray) { AmbariHostComponent hc = new AmbariHostComponent(); JsonObject hcJsonObject = hce.getAsJsonObject().get("HostRoles").getAsJsonObject(); hc.setHostName(hcJsonObject.get("host_name").getAsString()); hc.setStarted("STARTED".equals(hcJsonObject.get("state").getAsString())); hc.setName(hcJsonObject.get("component_name").getAsString()); hcList.add(hc); } } svc.setComponentsToHostComponentsMap(componentsToHostComponentsMap); return svc; } catch (HttpException e) { logger.warn("Unable to determine Ambari clusters", e); throw createRuntimeException(e); } catch (IOException e) { logger.warn("Unable to determine Ambari clusters", e); throw new RuntimeException(e.getMessage(), e); } } return null; } }