flink源码分析 - standalone模式下jobmanager启动过程配置文件加载
flink版本: flink-1.11.2
代码位置: org.apache.flink.runtime.entrypoint.StandaloneSessionClusterEntrypoint#main
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.runtime.entrypoint;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.runtime.entrypoint.component.DefaultDispatcherResourceManagerComponentFactory;
import org.apache.flink.runtime.entrypoint.parser.CommandLineParser;
import org.apache.flink.runtime.resourcemanager.StandaloneResourceManagerFactory;
import org.apache.flink.runtime.util.EnvironmentInformation;
import org.apache.flink.runtime.util.JvmShutdownSafeguard;
import org.apache.flink.runtime.util.SignalHandler;
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释： flink有三种方式执行应用程序：session mode, per-job mode, applocation mode
* 模型的区别主要包含：
* 1. 集群生命周期和资源隔离保证
* 2. 应用程序的main()方法是在客户机上执行还是在集群上执行
*/
/**
* Entry point for the standalone session cluster.
*/
public class StandaloneSessionClusterEntrypoint extends SessionClusterEntrypoint {
public StandaloneSessionClusterEntrypoint(Configuration configuration) {
super(configuration);
}
@Override
protected DefaultDispatcherResourceManagerComponentFactory createDispatcherResourceManagerComponentFactory(
Configuration configuration) {
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释：
* 1、参数是：StandaloneResourceManagerFactory 实例
* 2、返回值：DefaultDispatcherResourceManagerComponentFactory 实例
*/
return DefaultDispatcherResourceManagerComponentFactory
.createSessionComponentFactory(StandaloneResourceManagerFactory.getInstance());
}
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释： 入口
*/
public static void main(String[] args) {
// TODO_MA 注释：提供对 JVM 执行环境的访问的实用程序类，如执行用户(getHadoopUser())、启动选项或JVM版本。
// startup checks and logging
EnvironmentInformation.logEnvironmentInfo(LOG, StandaloneSessionClusterEntrypoint.class.getSimpleName(), args);
// TODO_MA 注释：注册一些信号处理
SignalHandler.register(LOG);
// TODO_MA 注释： 安装安全关闭的钩子
// TODO_MA 注释： 你的 Flink集群启动过程中，或者在启动好了之后的运行中，
// TODO_MA 注释： 都有可能接收到关闭集群的命令
JvmShutdownSafeguard.installAsShutdownHook(LOG);
EntrypointClusterConfiguration entrypointClusterConfiguration = null;
// TODO_MA 注释：
final CommandLineParser commandLineParser = new CommandLineParser<>(
new EntrypointClusterConfigurationParserFactory());
try {
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释： 对传入的参数进行解析
* 内部通过 EntrypointClusterConfigurationParserFactory 解析配置文件，
* 返回 EntrypointClusterConfiguration 为 ClusterConfiguration 的子类
*/
entrypointClusterConfiguration = commandLineParser.parse(args);
} catch(FlinkParseException e) {
LOG.error("Could not parse command line arguments {}.", args, e);
commandLineParser.printHelp(StandaloneSessionClusterEntrypoint.class.getSimpleName());
System.exit(1);
}
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释： 解析配置参数, 解析 flink 的配置文件： fink-conf.ymal
*/
Configuration configuration = loadConfiguration(entrypointClusterConfiguration);
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释：创建 StandaloneSessionClusterEntrypoint
*/
StandaloneSessionClusterEntrypoint entrypoint = new StandaloneSessionClusterEntrypoint(configuration);
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释：启动集群的entrypoint
* 这个方法接受的是父类 ClusterEntrypoint，可想而知其他几种启动方式也是通过这个方法。
*/
ClusterEntrypoint.runClusterEntrypoint(entrypoint);
}
}
加载配置文件主要分两步:
1. 解析命令行传入参数。核心代码:
entrypointClusterConfiguration = commandLineParser.parse(args);
原理参考:
flink源码分析 - 命令行参数解析-CommandLineParser-CSDN博客
2. flink-yaml配置加载:
核心代码:
Configuration configuration = loadConfiguration(entrypointClusterConfiguration);
其他部分略过，仅记录最关键yaml文件解析部分: 注意下方: org.apache.flink.configuration.GlobalConfiguration#loadYAMLResource
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.configuration;
import org.apache.flink.annotation.Internal;
import org.apache.flink.util.Preconditions;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.annotation.Nullable;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
/**
* Global configuration object for Flink. Similar to Java properties configuration
* objects it includes key-value pairs which represent the framework's configuration.
*/
@Internal
public final class GlobalConfiguration {
private static final Logger LOG = LoggerFactory.getLogger(GlobalConfiguration.class);
public static final String FLINK_CONF_FILENAME = "flink-conf.yaml";
// the keys whose values should be hidden
private static final String[] SENSITIVE_KEYS = new String[] {"password", "secret", "fs.azure.account.key"};
// the hidden content to be displayed
public static final String HIDDEN_CONTENT = "******";
// --------------------------------------------------------------------------------------------
private GlobalConfiguration() {}
// --------------------------------------------------------------------------------------------
/**
* Loads the global configuration from the environment. Fails if an error occurs during loading. Returns an
* empty configuration object if the environment variable is not set. In production this variable is set but
* tests and local execution/debugging don't have this environment variable set. That's why we should fail
* if it is not set.
* @return Returns the Configuration
*/
public static Configuration loadConfiguration() {
return loadConfiguration(new Configuration());
}
/**
* Loads the global configuration and adds the given dynamic properties
* configuration.
*
* @param dynamicProperties The given dynamic properties
* @return Returns the loaded global configuration with dynamic properties
*/
public static Configuration loadConfiguration(Configuration dynamicProperties) {
final String configDir = System.getenv(ConfigConstants.ENV_FLINK_CONF_DIR);
if (configDir == null) {
return new Configuration(dynamicProperties);
}
return loadConfiguration(configDir, dynamicProperties);
}
/**
* Loads the configuration files from the specified directory.
*
* YAML files are supported as configuration files.
*
* @param configDir
* the directory which contains the configuration files
*/
public static Configuration loadConfiguration(final String configDir) {
// TODO_MA 注释：
return loadConfiguration(configDir, null);
}
/**
* Loads the configuration files from the specified directory. If the dynamic properties
* configuration is not null, then it is added to the loaded configuration.
*
* @param configDir directory to load the configuration from
* @param dynamicProperties configuration file containing the dynamic properties. Null if none.
* @return The configuration loaded from the given configuration directory
*/
public static Configuration loadConfiguration(final String configDir, @Nullable final Configuration dynamicProperties) {
if (configDir == null) {
throw new IllegalArgumentException("Given configuration directory is null, cannot load configuration");
}
final File confDirFile = new File(configDir);
if (!(confDirFile.exists())) {
throw new IllegalConfigurationException(
"The given configuration directory name '" + configDir +
"' (" + confDirFile.getAbsolutePath() + ") does not describe an existing directory.");
}
// TODO_MA 注释： Flink 配置文件： flink-conf.yaml
// get Flink yaml configuration file
final File yamlConfigFile = new File(confDirFile, FLINK_CONF_FILENAME);
if (!yamlConfigFile.exists()) {
throw new IllegalConfigurationException(
"The Flink config file '" + yamlConfigFile +
"' (" + confDirFile.getAbsolutePath() + ") does not exist.");
}
// TODO_MA 注释： 读取 flink-conf.xml 配置文件
Configuration configuration = loadYAMLResource(yamlConfigFile);
if (dynamicProperties != null) {
configuration.addAll(dynamicProperties);
}
return configuration;
}
/**
* Loads a YAML-file of key-value pairs.
*
*
Colon and whitespace ": " separate key and value (one per line). The hash tag "#" starts a single-line comment.
*
*
Example:
*
*
* jobmanager.rpc.address: localhost # network address for communication with the job manager
* jobmanager.rpc.port : 6123 # network port to connect to for communication with the job manager
* taskmanager.rpc.port : 6122 # network port the task manager expects incoming IPC connections
*
*
* This does not span the whole YAML specification, but only the *syntax* of simple YAML key-value pairs (see issue
* #113 on GitHub). If at any point in time, there is a need to go beyond simple key-value pairs syntax
* compatibility will allow to introduce a YAML parser library.
*
* @param file the YAML file to read from
* @see YAML 1.2 specification
*/
private static Configuration loadYAMLResource(File file) {
// TODO_MA 注释： 存储 配置解析结果的 容器
final Configuration config = new Configuration();
/*************************************************
* TODO_MA 马中华 https://blog.csdn.net/zhongqi2513
* 注释： 读取 flink-conf.yaml 文件
*/
try (BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(file)))){
String line;
int lineNo = 0;
// TODO_MA 注释： 读取一行
while ((line = reader.readLine()) != null) {
lineNo++;
// 1. check for comments
/*
zhouxianfu 2023-07-30: 此处为了防止下面这种情况导致后期取值错误
key: value ## comment 以下是示例
high-availability.cluster-id: /flink-1.12.0_cluster_yarn ## 注意: yarn模式下不能配置这个参数，而是由yarn自动生成
*/
String[] comments = line.split("#", 2);
String conf = comments[0].trim();
// 2. get key and value
if (conf.length() > 0) {
String[] kv = conf.split(": ", 2);
// skip line with no valid key-value pair
if (kv.length == 1) {
LOG.warn("Error while trying to split key and value in configuration file " + file + ":" + lineNo + ": \"" + line + "\"");
continue;
}
String key = kv[0].trim();
String value = kv[1].trim();
// sanity check
if (key.length() == 0 || value.length() == 0) {
LOG.warn("Error after splitting key and value in configuration file " + file + ":" + lineNo + ": \"" + line + "\"");
continue;
}
LOG.info("Loading configuration property: {}, {}", key, isSensitive(key) ? HIDDEN_CONTENT : value);
config.setString(key, value);
}
}
} catch (IOException e) {
throw new RuntimeException("Error parsing YAML configuration.", e);
}
// TODO_MA 注释： 返回 Configuration
return config;
}
/**
* Check whether the key is a hidden key.
*
* @param key the config key
*/
public static boolean isSensitive(String key) {
Preconditions.checkNotNull(key, "key is null");
final String keyInLower = key.toLowerCase();
for (String hideKey : SENSITIVE_KEYS) {
if (keyInLower.length() >= hideKey.length()
&& keyInLower.contains(hideKey)) {
return true;
}
}
return false;
}
}