flink源码解读--2 入口类CliFrontend
参考文章： https://blog.csdn.net/weixin_43161811/article/details/103151644
从上篇文章，我们知道，flink脚本提交后，由CliFrontend main开始执行。
/** Submits the job based on the arguments. */
public static void main(final String[] args) {
// 1.打印基本的环境信息
EnvironmentInformation.logEnvironmentInfo(LOG, "Command Line Client", args);
// 2. find the configuration directory -- 获取配置文件目录：.../flink1.9.0/conf
final String configurationDirectory = getConfigurationDirectoryFromEnv();
// 3. load the global configuration -- 加载flink-conf.yaml中的全局配置转成Configuration对象
final Configuration configuration =
GlobalConfiguration.loadConfiguration(configurationDirectory);
// 4. load the custom command lines -- 加载用户输入的命令行、获取命令行参数
// customCommandLines添加org.apache.flink.yarn.cli.FlinkYarnSessionCli（configuration ，//configurationDirectory, //"y", "yarn"）构造对象和new DefaultCLI(configuration)
final List
loadCustomCommandLines(configuration, configurationDirectory);
try {
//5.创建CliFrontend对象
final CliFrontend cli = new CliFrontend(configuration, customCommandLines);
//6.加载 SecurityConfiguration类，是flink全局安全配置
SecurityUtils.install(new SecurityConfiguration(cli.configuration));
//7.根据命令行参数进行匹配，运行程序，获取程序执行的运行码
//调用CliFrontend的parseParameters方法， 解析命令行参数，运行具体的action【run】
//即cli.parseParameters(args)方法为最后的run(下述方法先做安全检查)
int retCode = SecurityUtils.getInstalledContext().runSecured(() -> cli.parseParameters(args));
//8.获取执行返回值，关闭提交程序
System.exit(retCode);
} catch (Throwable t) {
final Throwable strippedThrowable =
ExceptionUtils.stripException(t, UndeclaredThrowableException.class);
LOG.error("Fatal error while running command line interface.", strippedThrowable);
strippedThrowable.printStackTrace();
System.exit(31);
}
}
步骤4构造FlinkYarnSessionCli明细过程：
/**
* 初始化一个FlinkYarnSessionCli
* @param configuration 全局的配置
* @param configurationDirectory 全局的配置文件目录
* @param shortPrefix 命令行参数的缩写前缀 y
* @param longPrefix 命令行参数的展开前缀 yarn
* @param acceptInteractiveInput 是否接受交互型输入
* @throws FlinkException
*/
public FlinkYarnSessionCli(
Configuration configuration,
String configurationDirectory,
String shortPrefix,
String longPrefix,
boolean acceptInteractiveInput) throws FlinkException {
// 1. 初始化参数
super(configuration);
this.configurationDirectory = Preconditions.checkNotNull(configurationDirectory);
this.acceptInteractiveInput = acceptInteractiveInput;
// 2. 创建命令行选项
query = new Option(shortPrefix + "q", longPrefix + "query", false, "Display available YARN resources (memory, cores)");
applicationId = new Option(shortPrefix + "id", longPrefix + "applicationId", true, "Attach to running YARN session");
queue = new Option(shortPrefix + "qu", longPrefix + "queue", true, "Specify YARN queue.");
shipPath = new Option(shortPrefix + "t", longPrefix + "ship", true, "Ship files in the specified directory (t for transfer)");
flinkJar = new Option(shortPrefix + "j", longPrefix + "jar", true, "Path to Flink jar file");
jmMemory = new Option(shortPrefix + "jm", longPrefix + "jobManagerMemory", true, "Memory for JobManager Container with optional unit (default: MB)");
tmMemory = new Option(shortPrefix + "tm", longPrefix + "taskManagerMemory", true, "Memory per TaskManager Container with optional unit (default: MB)");
container = new Option(shortPrefix + "n", longPrefix + "container", true, "Number of YARN container to allocate (=Number of Task Managers)");
slots = new Option(shortPrefix + "s", longPrefix + "slots", true, "Number of slots per TaskManager");
dynamicproperties = Option.builder(shortPrefix + "D")
.argName("property=value")
.numberOfArgs(2)
.valueSeparator()
.desc("use value for given property")
.build();
streaming = new Option(shortPrefix + "st", longPrefix + "streaming", false, "Start Flink in streaming mode");
name = new Option(shortPrefix + "nm", longPrefix + "name", true, "Set a custom name for the application on YARN");
zookeeperNamespace = new Option(shortPrefix + "z", longPrefix + "zookeeperNamespace", true, "Namespace to create the Zookeeper sub-paths for high availability mode");
nodeLabel = new Option(shortPrefix + "nl", longPrefix + "nodeLabel", true, "Specify YARN node label for the YARN application");
help = new Option(shortPrefix + "h", longPrefix + "help", false, "Help for the Yarn session CLI.");
allOptions = new Options();
allOptions.addOption(flinkJar);
allOptions.addOption(jmMemory);
allOptions.addOption(tmMemory);
allOptions.addOption(container);
allOptions.addOption(queue);
allOptions.addOption(query);
allOptions.addOption(shipPath);
allOptions.addOption(slots);
allOptions.addOption(dynamicproperties);
allOptions.addOption(DETACHED_OPTION);
allOptions.addOption(SHUTDOWN_IF_ATTACHED_OPTION);
allOptions.addOption(YARN_DETACHED_OPTION);
allOptions.addOption(streaming);
allOptions.addOption(name);
allOptions.addOption(applicationId);
allOptions.addOption(zookeeperNamespace);
allOptions.addOption(nodeLabel);
allOptions.addOption(help);
// 3. 加载默认的yarn配置文件
this.yarnPropertiesFileLocation = configuration.getString(YarnConfigOptions.PROPERTIES_FILE_LOCATION);
final File yarnPropertiesLocation = getYarnPropertiesLocation(yarnPropertiesFileLocation);
// 4. 解析出yarn的配置参数
yarnPropertiesFile = new Properties();
if (yarnPropertiesLocation.exists()) {
LOG.info("Found Yarn properties file under {}.", yarnPropertiesLocation.getAbsolutePath());
try (InputStream is = new FileInputStream(yarnPropertiesLocation)) {
yarnPropertiesFile.load(is);
} catch (IOException ioe) {
throw new FlinkException("Could not read the Yarn properties file " + yarnPropertiesLocation +
". Please delete the file at " + yarnPropertiesLocation.getAbsolutePath() + '.', ioe);
}
final String yarnApplicationIdString = yarnPropertiesFile.getProperty(YARN_APPLICATION_ID_KEY);
if (yarnApplicationIdString == null) {
throw new FlinkException("Yarn properties file found but doesn't contain a " +
"Yarn application id. Please delete the file at " + yarnPropertiesLocation.getAbsolutePath());
}
try {
// 尝试将id转化成ApplicationId
yarnApplicationIdFromYarnProperties = ConverterUtils.toApplicationId(yarnApplicationIdString);
}
catch (Exception e) {
throw new FlinkException("YARN properties contains an invalid entry for " +
"application id: " + yarnApplicationIdString + ". Please delete the file at " +
yarnPropertiesLocation.getAbsolutePath(), e);
}
} else {
yarnApplicationIdFromYarnProperties = null;
}
// 5. 初始化yarn的配置
this.yarnConfiguration = new YarnConfiguration();
}
步骤7 cli.parseParameters(args))代码明细：
/**
* Parses the command line arguments and starts the requested action.
*
* @param args command line arguments of the client.
* @return The return code of the program
*/
public int parseParameters(String[] args) {
// check for action
if (args.length < 1) {
CliFrontendParser.printHelp(customCommandLines);
System.out.println("Please specify an action.");
return 1;
}
// get action 提取执行动作，比如run,list,cancel
String action = args[0];
// remove action from parameters 从参数中移除执行动作
final String[] params = Arrays.copyOfRange(args, 1, args.length);
try {
// do action
switch (action) {
case ACTION_RUN:
run(params);
return 0;
case ACTION_LIST:
list(params);
return 0;
case ACTION_INFO:
info(params);
return 0;
case ACTION_CANCEL:
cancel(params);
return 0;
case ACTION_STOP:
stop(params);
return 0;
case ACTION_SAVEPOINT:
savepoint(params);
return 0;
case "-h":
case "--help":
CliFrontendParser.printHelp(customCommandLines);
return 0;
case "-v":
case "--version":
String version = EnvironmentInformation.getVersion();
String commitID = EnvironmentInformation.getRevisionInformation().commitId;
System.out.print("Version: " + version);
System.out.println(commitID.equals(EnvironmentInformation.UNKNOWN) ? "" : ", Commit ID: " + commitID);
return 0;
default:
System.out.printf("\"%s\" is not a valid action.\n", action);
System.out.println();
System.out.println("Valid actions are \"run\", \"list\", \"info\", \"savepoint\", \"stop\", or \"cancel\".");
System.out.println();
System.out.println("Specify the version option (-v or --version) to print Flink version.");
System.out.println();
System.out.println("Specify the help option (-h or --help) to get help on the command.");
return 1;
}
} catch (CliArgsException ce) {
return handleArgException(ce);
} catch (ProgramParametrizationException ppe) {
return handleParametrizationException(ppe);
} catch (ProgramMissingJobException pmje) {
return handleMissingJobException();
} catch (Exception e) {
return handleError(e);
}
}
我们重点看下flink run 的逻辑，限于篇幅，在下一篇文章继续分析。