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Fayson的github： https://github.com/fayson/cdhproject
提示：代码块部分可以左右滑动查看噢
1.文档编写目的
用户在使用CDH集群大数据平台时会有需求在自己的统一管理平台上通过API接口能够动态的设置Yarn资源池，Cloudera Manager提供了丰富的API接口对CDH集群的各个服务进行配置等操作，在上一篇文章Fayson介绍了《如何使用curl命令调用CM的API动态配置Yarn资源池》，本篇文章Fayson主要介绍如何使用Java调用CM的API接口动态的配置Yarn资源池并使其生效。
- 本次Fayson的测试环境
1.CM和CDH版本为5.15
2.获取Cloudera Manager的API接口
1.登录Cloudera Manager，点击菜单“支持”->“API文档”
2.进入API文档界面，可以看到API的版本为v19
3.本篇文章要用到的API接口说明
代码语言：javascript复制http://<cm_server>:7180/clusters
http://<cm_server>:7180/api/v19/clusters/{clusterName}/services/{serviceName}/config
http://<cm_server>:7180/api/v19/clusters/{clusterName}/commands/poolsRefresh（可左右滑动）
共使用到3个接口：
第一个接口用于获取集群的信息，如集群的名称，以供2、3接口使用
第二个接口用于设置Yarn的资源池，接口中的{serviceName}修改为yarn
第三个接口用于刷新Yarn的资源池
3.Java示例工程
1.使用Maven创建cmapi-demo的Java工程，pom.xml内容如下：
代码语言：javascript复制<dependencies>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.4</version>
</dependency>
<dependency>
<groupId>net.sf.json-lib</groupId>
<artifactId>json-lib</artifactId>
<version>2.4</version>
<classifier>jdk15</classifier>
</dependency>
</dependencies>（可左右滑动）
2.创建HttpUtils.java工具类，该类主要使用HttpClient方式调用CM的API接口
代码语言：javascript复制package com.cloudera.utils;
import org.apache.commons.lang.StringEscapeUtils;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.client.methods.HttpDelete;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.BasicCredentialsProvider;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import java.io.IOException;
import java.net.URI;
import java.util.Map;
/**
* package: com.cloudera
* describe: Http请求工具类
* creat_user: Fayson
* email: htechinfo@163.com
* creat_date: 2018/2/12
* creat_time: 下午12:16
* 公众号：Hadoop实操
*/
public class HttpUtils {
/**
* Get方式用户名和密码认证
* @param url
* @param headers
* @param username
* @param password
* @return
*/
public static String getAccessByAuth(String url, Map<String, String> headers, String username, String password) {
String result = null;
URI uri = URI.create(url);
CredentialsProvider credsProvider = new BasicCredentialsProvider();
credsProvider.setCredentials(new AuthScope(uri.getHost(), uri.getPort()),
new UsernamePasswordCredentials(username, password));
CloseableHttpClient httpClient = HttpClients.custom().setDefaultCredentialsProvider(credsProvider)
.build();
HttpGet httpGet = new HttpGet(uri);
if(headers != null && headers.size() > 0){
headers.forEach((K,V)->httpGet.addHeader(K,V));
}
HttpResponse response = null;
try {
response = httpClient.execute(httpGet);
HttpEntity resultEntity = response.getEntity();
result = EntityUtils.toString(resultEntity);
return result;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
/**
* Post方式用户名和密码认证
* @param url
* @param headers
* @param data
* @param username
* @param password
* @return
*/
public static String postAccessByAuth(String url, Map<String, String> headers, String data, String username, String password) {
String result = null;
URI uri = URI.create(url);
CredentialsProvider credsProvider = new BasicCredentialsProvider();
credsProvider.setCredentials(new AuthScope(uri.getHost(), uri.getPort()),
new UsernamePasswordCredentials(username, password));
CloseableHttpClient httpClient = HttpClients.custom()
.setDefaultCredentialsProvider(credsProvider)
.build();
HttpPost post = new HttpPost(uri);
if(headers != null && headers.size() > 0){
headers.forEach((K,V)->post.addHeader(K,V));
}
try {
if(data != null) {
StringEntity entity = new StringEntity(data);
entity.setContentEncoding("UTF-8");
entity.setContentType("application/json");
post.setEntity(entity);
}
HttpResponse response = httpClient.execute(post);
HttpEntity resultEntity = response.getEntity();
result = EntityUtils.toString(resultEntity);
return result;
} catch (Exception e) {
e.printStackTrace();
}
return result;
}
/**
* Put方式用户名和密码认证方式
* @param url
* @param headers
* @param data
* @param username
* @param password
* @return
*/
public static String putAccessByAuth(String url, Map<String, String> headers, String data, String username, String password) {
String result = null;
URI uri = URI.create(url);
CredentialsProvider credsProvider = new BasicCredentialsProvider();
credsProvider.setCredentials(new AuthScope(uri.getHost(), uri.getPort()),
new UsernamePasswordCredentials(username, password));
CloseableHttpClient httpClient = HttpClients.custom()
.setDefaultCredentialsProvider(credsProvider)
.build();
HttpPut put = new HttpPut(uri);
if(headers != null && headers.size() > 0){
headers.forEach((K,V)->put.addHeader(K,V));
}
try {
if(data != null) {
StringEntity entity = new StringEntity(data);
entity.setContentEncoding("UTF-8");
entity.setContentType("application/json");
put.setEntity(entity);
}
HttpResponse response = httpClient.execute(put);
HttpEntity resultEntity = response.getEntity();
result = EntityUtils.toString(resultEntity);
return result;
} catch (Exception e) {
e.printStackTrace();
}
return result;
}
}（可左右滑动）
3.创建RestApiConfPool.java类，调用CM API接口设置资源池
代码语言：javascript复制package com.cloudera;
import com.cloudera.api.model.ApiConfig;
import com.cloudera.utils.HttpUtils;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import org.apache.commons.lang.StringEscapeUtils;
import java.util.HashMap;
/**
* package: com.cloudera
* describe: 通过CM提供的API配置Yarn动态资源池
* creat_user: Fayson
* email: htechinfo@163.com
* creat_date: 2018/8/7
* creat_time: 下午3:14
* 公众号：Hadoop实操
*/
public class RestApiConfPool {
private static String REQ_CLUSTER_URL = "http://cdh01.fayson.com:7180/api/v19/clusters";
private static String REQ_SETPOOL_URL = "http://cdh01.fayson.com:7180/api/v19/clusters/cluster/services/yarn/config";
private static String REQ_FRESHPOOL_URL = "http://cdh01.fayson.com:7180/api/v19/clusters/cluster/commands/poolsRefresh";
private static String USERNAME = "admin";
private static String PASSWORD = "admin";
public static void main(String[] args) {
HashMap<String, String> headers = new HashMap<>();
headers.put("Content-Type", "application/json");
headers.put("Accept", "application/json");
//获取CM管理的Cluster集群名称
String result = HttpUtils.getAccessByAuth(REQ_CLUSTER_URL, headers, USERNAME, PASSWORD);
System.out.println("获取集群信息：" result);
//定义资源池配置的JSON配置
JSONObject requestJson = new JSONObject();
JSONArray jsonArray = new JSONArray();
JSONObject yarnjson = new JSONObject();
String pool_conf = "{\"defaultFairSharePreemptionThreshold\":null,\"defaultFairSharePreemptionTimeout\":null,\"defaultMinSharePreemptionTimeout\":null,\"defaultQueueSchedulingPolicy\":\"fair\",\"queueMaxAMShareDefault\":null,\"queueMaxAppsDefault\":null,\"queuePlacementRules\":[{\"create\":true,\"name\":\"specified\",\"queue\":null,\"rules\":null},{\"create\":null,\"name\":\"nestedUserQueue\",\"queue\":null,\"rules\":[{\"create\":true,\"name\":\"default\",\"queue\":\"users\",\"rules\":null}]},{\"create\":null,\"name\":\"default\",\"queue\":null,\"rules\":null}],\"queues\":[{\"aclAdministerApps\":\"*\",\"aclSubmitApps\":\"*\",\"allowPreemptionFrom\":null,\"fairSharePreemptionThreshold\":null,\"fairSharePreemptionTimeout\":null,\"minSharePreemptionTimeout\":null,\"name\":\"root\",\"queues\":[{\"aclAdministerApps\":null,\"aclSubmitApps\":null,\"allowPreemptionFrom\":null,\"fairSharePreemptionThreshold\":null,\"fairSharePreemptionTimeout\":null,\"minSharePreemptionTimeout\":null,\"name\":\"default\",\"queues\":[],\"schedulablePropertiesList\":[{\"impalaDefaultQueryMemLimit\":null,\"impalaDefaultQueryOptions\":null,\"impalaMaxMemory\":null,\"impalaMaxQueuedQueries\":null,\"impalaMaxRunningQueries\":null,\"impalaQueueTimeout\":null,\"maxAMShare\":null,\"maxChildResources\":null,\"maxResources\":null,\"maxRunningApps\":null,\"minResources\":null,\"scheduleName\":\"default\",\"weight\":1.0}],\"schedulingPolicy\":\"drf\",\"type\":null},{\"aclAdministerApps\":null,\"aclSubmitApps\":null,\"allowPreemptionFrom\":null,\"fairSharePreemptionThreshold\":null,\"fairSharePreemptionTimeout\":null,\"minSharePreemptionTimeout\":null,\"name\":\"users\",\"queues\":[],\"schedulablePropertiesList\":[{\"impalaDefaultQueryMemLimit\":null,\"impalaDefaultQueryOptions\":null,\"impalaMaxMemory\":null,\"impalaMaxQueuedQueries\":null,\"impalaMaxRunningQueries\":null,\"impalaQueueTimeout\":null,\"maxAMShare\":null,\"maxChildResources\":null,\"maxResources\":null,\"maxRunningApps\":null,\"minResources\":null,\"scheduleName\":\"default\",\"weight\":2.0}],\"schedulingPolicy\":\"drf\",\"type\":\"parent\"}],\"schedulablePropertiesList\":[{\"impalaDefaultQueryMemLimit\":null,\"impalaDefaultQueryOptions\":null,\"impalaMaxMemory\":null,\"impalaMaxQueuedQueries\":null,\"impalaMaxRunningQueries\":null,\"impalaQueueTimeout\":null,\"maxAMShare\":null,\"maxChildResources\":null,\"maxResources\":null,\"maxRunningApps\":null,\"minResources\":null,\"scheduleName\":\"default\",\"weight\":1.0}],\"schedulingPolicy\":\"drf\",\"type\":null}],\"userMaxAppsDefault\":null,\"users\":[]}";
yarnjson.put("name", "yarn_fs_scheduled_allocations");
yarnjson.put("value", pool_conf);
jsonArray.add(yarnjson);
requestJson.put("items", jsonArray);
//注意使用PUT提交，否则会请求失败
result = HttpUtils.putAccessByAuth(REQ_SETPOOL_URL, headers, StringEscapeUtils.unescapeJava(requestJson.toString()), USERNAME, PASSWORD);
System.out.println("动态设置Yarn资源池：" result);
//刷新资源池
result = HttpUtils.postAccessByAuth(REQ_FRESHPOOL_URL, headers, null, USERNAME, PASSWORD);
System.out.println("刷新资源池配置：" result);
}
}（可左右滑动）
4.示例运行
1.设置资源池前Yarn的配置如下
2.在RestApiConfPool.java类中运行，如下图显示运行成功
3.登陆Cloudera Manager查看资源池配置，已更新为设置的值且已生效
5.总结
1.通过API接口动态的配置Yarn的资源池，首先要获取Yarn服务所在集群名称，通过接口进行动态设置，设置完成后需要调用刷新的API接口使其生效。
2.在设置Yarn资源池时调用的API接口为PUT方式提交，如果指定其他方式会导致设置失败。
3.设置资源池的JSON字符串，需要注意value跟的数据为转义的字符串，必须带“”,否则会设置失败。
4.在Java 代码中字符串“”会被转义”\”，在设置时需要使用Java工具类提供更的方法StringEscapeUtils.unescapeJava()将转义字符串去掉。
GitHub地址：
https://github.com/fayson/cdhproject/blob/master/cmapidemo/src/main/java/com/cloudera/RestApiConfPool.java
https://github.com/fayson/cdhproject/tree/master/cmapidemo/src/main/java/com/cloudera/utils
提示：代码块部分可以左右滑动查看噢
为天地立心，为生民立命，为往圣继绝学，为万世开太平。 温馨提示：如果使用电脑查看图片不清晰，可以使用手机打开文章单击文中的图片放大查看高清原图。
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