通过API访问Ambari的配置

 HttpClient client = new HttpClient();
 Base64.Encoder encoder = Base64.getEncoder();
 HttpMethod method = new GetMethod("http://hdp0:8080/api/v1/clusters/HDP/configurations");
 method.addRequestHeader("Authorization",
         "Basic " + encoder.encodeToString("admin:admin".getBytes("iso-8859-1")));
 method.addRequestHeader("X-Requested-By", "ambari");
 client.executeMethod(method);
 // 获取YARN的capacity-scheduler属性信息
 AmbariClient aClient = new AmbariClient("10.1.108.45", "8080", "admin", "admin");
 String typeName = "capacity-scheduler";
 String propertieName = "yarn.scheduler.capacity.root.unfunded.capacity";
 Map<String, Map<String, String>> map = aClient.getServiceConfigMap(typeName);
 for (String key : map.keySet()) {
     System.out.println("key: " + key + ";");
     Map<String, String> kvs = map.get(key);
     for (String name : kvs.keySet()) {
         if (name.equals(propertieName)) {
             System.out.println("name: " + name + "; value: " + kvs.get(name));
         }
     }
 }
 // 修改配置信息
 Map<String, String> mapUpdate = new HashMap<String, String>();

 mapUpdate.put(propertieName, "55");
 aClient.modifyConfiguration(typeName, mapUpdate);

 map = aClient.getServiceConfigMap(typeName);
 for (String key : map.keySet()) {
     System.out.println("key: " + key + ";");
     Map<String, String> kvs = map.get(key);
     for (String name : kvs.keySet()) {
         if (name.equals(propertieName)) {
             System.out.println("name: " + name + "; value: " + kvs.get(name));
         }
     }
 }

Ambari所有的服务的组件列表：

{"service_name":"HDFS","component_name":"DATANODE","hosts":"c6401.ambari.apache.org"},
{"service_name":"HDFS","component_name":"HDFS_CLIENT","hosts":"c6401.ambari.apache.org"},
{"service_name":"HDFS","component_name":"NAMENODE","hosts":"c6401.ambari.apache.org"},   
{"service_name":"HDFS","component_name":"SECONDARY_NAMENODE","hosts":"c6401.ambari.apache.org"},

{"service_name":"HIVE","component_name":"HCAT","hosts":"c6401.ambari.apache.org"},
{"service_name":"HIVE","component_name":"HIVE_CLIENT","hosts":"c6401.ambari.apache.org"},
{"service_name":"HIVE","component_name":"HIVE_METASTORE","hosts":"c6401.ambari.apache.org"},
{"service_name":"HIVE","component_name":"HIVE_SERVER","hosts":"c6401.ambari.apache.org"},
{"service_name":"HIVE","component_name":"MYSQL_SERVER","hosts":"c6401.ambari.apache.org"},
{"service_name":"HIVE","component_name":"WEBHCAT_SERVER","hosts":"c6401.ambari.apache.org"},

{"service_name":"YARN","component_name":"APP_TIMELINE_SERVER","hosts":"c6401.ambari.apache.org"},
{"service_name":"YARN","component_name":"NODEMANAGER","hosts":"c6401.ambari.apache.org"},
{"service_name":"YARN","component_name":"RESOURCEMANAGER","hosts":"c6401.ambari.apache.org"},
{"service_name":"YARN","component_name":"YARN_CLIENT","hosts":"c6401.ambari.apache.org"},

{"service_name":"MAPREDUCE2","component_name":"HISTORYSERVER","hosts":"c6401.ambari.apache.org"},
{"service_name":"MAPREDUCE2","component_name":"MAPREDUCE2_CLIENT","hosts":"c6401.ambari.apache.org"},
{"service_name":"AMBARI_METRICS","component_name":"METRICS_COLLECTOR","hosts":"c6401.ambari.apache.org"},
{"service_name":"AMBARI_METRICS","component_name":"METRICS_MONITOR","hosts":"c6401.ambari.apache.org"},

{"service_name":"PIG","component_name":"PIG","hosts":"c6401.ambari.apache.org"},

{"service_name":"TEZ","component_name":"TEZ_CLIENT","hosts":"c6401.ambari.apache.org"},

{"service_name":"ZOOKEEPER","component_name":"ZOOKEEPER_CLIENT","hosts":"c6401.ambari.apache.org"},
{"service_name":"ZOOKEEPER","component_name":"ZOOKEEPER_SERVER","hosts":"c6401.ambari.apache.org"}