package com.baidu.disconf.client.fetcher.inner.restful;
import java.io.File;
import java.net.URL;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Invocation;
import javax.ws.rs.client.WebTarget;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import org.glassfish.jersey.jackson.JacksonFeature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.baidu.disconf.client.config.inner.DisClientSysConfig;
import com.baidu.disconf.client.fetcher.inner.restful.core.RemoteUrl;
import com.baidu.disconf.client.fetcher.inner.restful.core.UnreliableInterface;
import com.baidu.disconf.client.fetcher.inner.restful.file.FetchConfFile;
import com.baidu.disconf.client.fetcher.inner.restful.http.RestfulGet;
import com.baidu.disconf.client.fetcher.inner.restful.retry.RetryProxy;
import com.baidu.utils.ConfigLoaderUtils;
import com.baidu.utils.OsUtil;
/**
* RestFul的一个实现,单例实现
*
* @author liaoqiqi
* @version 2014-6-10
*/
public class RestfulMgr {
protected static final Logger LOGGER = LoggerFactory
.getLogger(RestfulMgr.class);
private RestfulMgr() {
}
/**
* 类级的内部类，也就是静态的成员式内部类，该内部类的实例与外部类的实例 没有绑定关系，而且只有被调用到时才会装载，从而实现了延迟加载。
*/
private static class SingletonHolder {
/**
* 静态初始化器，由JVM来保证线程安全
*/
private static RestfulMgr instance = new RestfulMgr();
}
public static RestfulMgr getInstance() {
return SingletonHolder.instance;
}
/**
* 连接器
*/
private Client client = null;
/**
*
* @Description: 初始化
*
* @throws Exception
* @return void
* @author liaoqiqi
* @date 2013-6-16
*/
public void init() throws Exception {
client = ClientBuilder.newBuilder().register(JacksonFeature.class)
.build();
if (client == null) {
throw new Exception("RestfulMgr init failed!");
}
}
/**
*
* @return
*/
public boolean isInit() {
if (client == null) {
return false;
}
return true;
}
/**
* 获取JSON数据
*
* @param clazz
* @param remoteUrl
* @return
* @throws Exception
*/
public <T> T getJsonData(Class<T> clazz, RemoteUrl remoteUrl)
throws Exception {
for (URL url : remoteUrl.getUrls()) {
WebTarget webtarget = client.target(url.toURI());
LOGGER.info("start to query url : " + webtarget.getUri().toString());
Invocation.Builder builder = webtarget
.request(MediaType.APPLICATION_JSON_TYPE);
// 可重试的下载
UnreliableInterface unreliableImpl = new RestfulGet(builder);
try {
Response response = (Response) RetryProxy
.retry(unreliableImpl,
DisClientSysConfig.getInstance().CONF_SERVER_URL_RETRY_TIMES,
DisClientSysConfig.getInstance().CONF_SERVER_URL_RETRY_SLEEP_SECONDS);
T t = (T) response.readEntity(clazz);
return t;
} catch (Exception e) {
try {
Thread.sleep(1000);
} catch (InterruptedException e1) {
}
}
}
throw new Exception();
}
/**
*
* @Description：关闭
*
* @return void
* @author liaoqiqi
* @date 2013-6-16
*/
public void close() {
if (client != null) {
client.close();
}
}
/**
*
*
* @param remoteUrl
* 远程地址
* @param fileName
* 文件名
* @param localTmpFileDir
* 本地临时 文件地址
* @param localFileDir
* 本地文件地址
* @param isTransfer2Classpath
* 是否将下载的文件放到Classpath目录下
* @return 如果是放到Classpath目录下，则返回相对Classpath的路径，如果不是，则返回全路径
* @throws Exception
*/
public String downloadFromServer(RemoteUrl remoteUrl, String fileName,
String localTmpFileDir, String localFileDir,
boolean isTransfer2Classpath) throws Exception {
// 本地临时全路径
String localTmpFilePath = OsUtil.pathJoin(localTmpFileDir, fileName);
// 本地路径
String localFilePath = OsUtil.pathJoin(localFileDir, fileName);
// 相应的File对象
File localTmpFile = new File(localTmpFilePath);
File localFile = new File(localFilePath);
if (localFile.exists()) {
localFile.delete();
}
try {
// 可重试的下载
retry4ConfDownload(
remoteUrl,
localTmpFile,
DisClientSysConfig.getInstance().CONF_SERVER_URL_RETRY_TIMES,
DisClientSysConfig.getInstance().CONF_SERVER_URL_RETRY_SLEEP_SECONDS);
// 从临时文件夹迁移到下载文件夹
OsUtil.transferFile(localTmpFile, localFile);
// 再次转移至classpath目录下
if (isTransfer2Classpath) {
File classpathFile = getLocalDownloadFileInClasspath(fileName);
if (classpathFile != null) {
// 从下载文件夹复制到classpath
OsUtil.transferFile(localFile, classpathFile);
localFile = classpathFile;
} else {
LOGGER.warn("classpath is null, cannot transfer "
+ fileName + " to classpath");
}
}
LOGGER.info("Move to: " + localFile.getAbsolutePath());
} catch (Exception e) {
LOGGER.warn("download file failed, using previous download file.",
e);
}
//
// 下载失败
//
if (!localFile.exists()) {
throw new Exception("targe file cannot be found! " + fileName);
}
//
// 下面为下载成功
//
// 如果是使用CLASS路径的，则返回相对classpath的路径
if (!ConfigLoaderUtils.CLASS_PATH.isEmpty()) {
String relavivePathString = OsUtil.getRelativePath(localFile,
new File(ConfigLoaderUtils.CLASS_PATH));
if (relavivePathString != null) {
if (new File(relavivePathString).isFile()) {
return relavivePathString;
}
}
}
// 否则, 返回全路径
return localFile.getAbsolutePath();
}
/**
*
* Retry封装 RemoteUrl 支持多Server的下载
*
* @param remoteUrl
* @param localTmpFile
* @param retryTimes
* @param sleepSeconds
* @return
*/
private static Object retry4ConfDownload(RemoteUrl remoteUrl,
File localTmpFile, int retryTimes, int sleepSeconds)
throws Exception {
for (URL url : remoteUrl.getUrls()) {
// 可重试的下载
UnreliableInterface unreliableImpl = new FetchConfFile(url,
localTmpFile);
try {
return RetryProxy.retry(unreliableImpl, retryTimes,
sleepSeconds);
} catch (Exception e) {
try {
Thread.sleep(1000);
} catch (InterruptedException e1) {
}
}
}
throw new Exception();
}
/**
*
* @Description: 获取在CLASSPATH下的文件，如果找不到CLASSPATH，则返回null
*
* @param fileName
* @return
* @throws Exception
* @return File
* @author liaoqiqi
* @date 2013-6-20
*/
private static File getLocalDownloadFileInClasspath(String fileName)
throws Exception {
String classpath = ConfigLoaderUtils.CLASS_PATH;
if (classpath == null) {
return null;
}
File file = new File(OsUtil.pathJoin(classpath, fileName));
return file;
}
}