Ambari的API调用

　　GET api/v1/clusters/HDP/configurations可以获得所有的配置信息（例如，http://hdp0:8080/api/v1/clusters/HDP/configurations）；但是只是一级信息；

　　比如我想要获得yarn的scheduler的节点信息，将会找到：

 {
       "href" : "http://hdp0:8080/api/v1/clusters/HDP/configurations?type=capacity-scheduler&tag=version1",
       "tag" : "version1",
       "type" : "capacity-scheduler",
       "version" : 1,
       "Config" : {
         "cluster_name" : "HDP",
         "stack_id" : "HDP-2.6"
       }
     }

　　这里注意，type就是配置页面的配置项的名称，在配置页面中该配置项为“Capacity Scheduler”，处理的时候，中间的空格处理为"-"，全字小写即使节点名称。然后，通过访问href指定的链接：http://hdp0:8080/api/v1/clusters/HDP/configurations?type=capacity-scheduler&tag=version1就可以看到该配置的详细信息

 {
   "href" : "http://hdp0:8080/api/v1/clusters/HDP/configurations?type=capacity-scheduler&tag=version1",
   "items" : [
     {
       "href" : "http://hdp0:8080/api/v1/clusters/HDP/configurations?type=capacity-scheduler&tag=version1",
       "tag" : "version1",
       "type" : "capacity-scheduler",
       "version" : 1,
       "Config" : {
         "cluster_name" : "HDP",
         "stack_id" : "HDP-2.6"
       },
       "properties" : {
         "capacity-scheduler" : "null",
         "yarn.scheduler.capacity.default.minimum-user-limit-percent" : "100",
         "yarn.scheduler.capacity.maximum-am-resource-percent" : "0.2",
         "yarn.scheduler.capacity.maximum-applications" : "10000",
         "yarn.scheduler.capacity.node-locality-delay" : "40",
         "yarn.scheduler.capacity.resource-calculator" : "org.apache.hadoop.yarn.util.resource.DefaultResourceCalculator",
         "yarn.scheduler.capacity.root.accessible-node-labels" : "*",
         "yarn.scheduler.capacity.root.acl_administer_queue" : "*",
         "yarn.scheduler.capacity.root.capacity" : "100",
         "yarn.scheduler.capacity.root.default.acl_administer_jobs" : "*",
         "yarn.scheduler.capacity.root.default.acl_submit_applications" : "*",
         "yarn.scheduler.capacity.root.default.capacity" : "100",
         "yarn.scheduler.capacity.root.default.maximum-capacity" : "100",
         "yarn.scheduler.capacity.root.default.state" : "RUNNING",
         "yarn.scheduler.capacity.root.default.user-limit-factor" : "1",
         "yarn.scheduler.capacity.root.queues" : "default"
       }
     }
   ]
 }

参考：https://github.com/apache/ambari/blob/trunk/ambari-server/docs/api/v1/configuration.md