RunNiFi.java 源码解读
时间:2022-07-24
本文章向大家介绍RunNiFi.java 源码解读，主要内容包括其使用实例、应用技巧、基本知识点总结和需要注意事项，具有一定的参考价值，需要的朋友可以参考一下。
RunNiFi类是由 nifi.sh脚本执行java命令指定的主类，RunNiFi类主要是干一些 查找文件，接受脚本指令，启动停止NIFI进程(主类 org.apache.nifi.NiFi)，自动重启NIFI，发送NIFI通知等等操作；关于代码的详细解读都在注释当中，可以从 main方法下自行跟踪阅读(自己跟着源码逻辑读更好)：
package org.apache.nifi.bootstrap;
/**
* 这个类通过查找以下位置来查找bootstrap.conf文件:
* java系统变量 org.apache.nifi.bootstrap.config.file
* 环境变量(脚本中设置)${NIFI_HOME}/./conf/bootstrap.conf
* ./conf/bootstrap.conf ./ 是当前类所在目录
* 如果bootstrap.conf找不到，抛出FileNotFoundException
*/
public class RunNiFi {
public static final String DEFAULT_CONFIG_FILE = "./conf/bootstrap.conf";
public static final String DEFAULT_JAVA_CMD = "java";
public static final String DEFAULT_PID_DIR = "bin";
public static final String DEFAULT_LOG_DIR = "./logs";
public static final String GRACEFUL_SHUTDOWN_PROP = "graceful.shutdown.seconds";
public static final String DEFAULT_GRACEFUL_SHUTDOWN_VALUE = "20";
public static final String NOTIFICATION_SERVICES_FILE_PROP = "notification.services.file";
public static final String NOTIFICATION_ATTEMPTS_PROP = "notification.max.attempts";
public static final String NIFI_START_NOTIFICATION_SERVICE_IDS_PROP = "nifi.start.notification.services";
public static final String NIFI_STOP_NOTIFICATION_SERVICE_IDS_PROP = "nifi.stop.notification.services";
public static final String NIFI_DEAD_NOTIFICATION_SERVICE_IDS_PROP = "nifi.dead.notification.services";
public static final String NIFI_PID_DIR_PROP = "org.apache.nifi.bootstrap.config.pid.dir";
public static final String NIFI_PID_FILE_NAME = "nifi.pid";
public static final String NIFI_STATUS_FILE_NAME = "nifi.status";
public static final String NIFI_LOCK_FILE_NAME = "nifi.lock";
public static final String NIFI_BOOTSTRAP_SENSITIVE_KEY = "nifi.bootstrap.sensitive.key";
public static final String PID_KEY = "pid";
public static final int STARTUP_WAIT_SECONDS = 60;
public static final String SHUTDOWN_CMD = "SHUTDOWN";
public static final String PING_CMD = "PING";
public static final String DUMP_CMD = "DUMP";
private volatile boolean autoRestartNiFi = true;
private volatile int ccPort = -1;
private volatile long nifiPid = -1L;
private volatile String secretKey;
private volatile ShutdownHook shutdownHook;
private volatile boolean nifiStarted;
private final Lock startedLock = new ReentrantLock();
private final Lock lock = new ReentrantLock();
private final Condition startupCondition = lock.newCondition();
private final File bootstrapConfigFile;
// 默认情况下，当应用程序启动时，这些将被记录到控制台(就是我们nifi.sh start 时看到的日志)
private final Logger cmdLogger = LoggerFactory.getLogger("org.apache.nifi.bootstrap.Command");
// 默认情况下，这些将被写入日志文件
private final Logger defaultLogger = LoggerFactory.getLogger(RunNiFi.class);
private final ExecutorService loggingExecutor;
private volatile Set<Future<?>> loggingFutures = new HashSet<>(2);
// nifi启动 停止 异常结束的通知服务
private final NotificationServiceManager serviceManager;
public RunNiFi(final File bootstrapConfigFile, final boolean verbose) throws IOException {
this.bootstrapConfigFile = bootstrapConfigFile;
//设置日志线程池 大小为2 一个写 文件 一个输出控制台 ，都是守护线程
loggingExecutor = Executors.newFixedThreadPool(2, new ThreadFactory() {
@Override
public Thread newThread(final Runnable runnable) {
final Thread t = Executors.defaultThreadFactory().newThread(runnable);
t.setDaemon(true);
t.setName("NiFi logging handler");
return t;
}
});
serviceManager = loadServices();
}
private static void printUsage() {
System.out.println("Usage:");
System.out.println();
System.out.println("java org.apache.nifi.bootstrap.RunNiFi [<-verbose>] <command> [options]");
System.out.println();
System.out.println("Valid commands include:");
System.out.println("");
System.out.println("Start : Start a new instance of Apache NiFi");
System.out.println("Stop : Stop a running instance of Apache NiFi");
System.out.println("Restart : Stop Apache NiFi, if it is running, and then start a new instance");
System.out.println("Status : Determine if there is a running instance of Apache NiFi");
System.out.println("Dump : Write a Thread Dump to the file specified by [options], or to the log if no file is given");
System.out.println("Run : Start a new instance of Apache NiFi and monitor the Process, restarting if the instance dies");
System.out.println();
}
private static String[] shift(final String[] orig) {
return Arrays.copyOfRange(orig, 1, orig.length);
}
// 比如传入参数 start
public static void main(String[] args) throws IOException, InterruptedException {
if (args.length < 1 || args.length > 3) {
printUsage();
return;
}
File dumpFile = null;
boolean verbose = false;
//检测是否是多参数 传入start 显然false
if (args[0].equals("-verbose")) {
verbose = true;
//如果参数冗余，取第一个参数 copy过来
args = shift(args);
}
final String cmd = args[0];
if (cmd.equals("dump")) {
if (args.length > 1) {
dumpFile = new File(args[1]);
} else {
dumpFile = null;
}
}
//检测第一个参数是否合规 不合规就打印提示
switch (cmd.toLowerCase()) {
case "start":
case "run":
case "stop":
case "status":
case "dump":
case "restart":
case "env":
break;
default:
printUsage();
return;
}
//获取bootsrap.conf -> ${NIFI_HOME}/./conf/bootstrap.conf
final File configFile = getDefaultBootstrapConfFile();
// 实例化 RunNiFi
final RunNiFi runNiFi = new RunNiFi(configFile, verbose);
Integer exitStatus = null;
// 判断参数 先看 start
switch (cmd.toLowerCase()) {
case "start":
runNiFi.start();
break;
case "run":
runNiFi.start();
break;
case "stop":
runNiFi.stop();
break;
case "status":
exitStatus = runNiFi.status();
break;
case "restart":
runNiFi.stop();
runNiFi.start();
break;
case "dump":
runNiFi.dump(dumpFile);
break;
case "env":
runNiFi.env();
break;
}
if (exitStatus != null) {
System.exit(exitStatus);
}
}
/**
* 返回 ${NIFI_HOME}/./conf/bootstrap.conf NIFI_HOME这个环境变量在启动脚本中就设置好了
*/
private static File getDefaultBootstrapConfFile() {
String configFilename = System.getProperty("org.apache.nifi.bootstrap.config.file");
if (configFilename == null) {
final String nifiHome = System.getenv("NIFI_HOME");
if (nifiHome != null) {
final File nifiHomeFile = new File(nifiHome.trim());
final File configFile = new File(nifiHomeFile, DEFAULT_CONFIG_FILE);
configFilename = configFile.getAbsolutePath();
}
}
if (configFilename == null) {
configFilename = DEFAULT_CONFIG_FILE;
}
final File configFile = new File(configFilename);
return configFile;
}
/*
* 装载通知服务 NIFI 启动 停止 死掉的通知
**/
private NotificationServiceManager loadServices() throws IOException {
//读取 bootstrap.conf配置文件
final File bootstrapConfFile = this.bootstrapConfigFile;
final Properties properties = new Properties();
try (final FileInputStream fis = new FileInputStream(bootstrapConfFile)) {
properties.load(fis);
}
final NotificationServiceManager manager = new NotificationServiceManager();
// notification.max.attempts 最大尝试次数
final String attemptProp = properties.getProperty(NOTIFICATION_ATTEMPTS_PROP);
if (attemptProp != null) {
try {
// 转int
final int maxAttempts = Integer.parseInt(attemptProp.trim());
if (maxAttempts >= 0) {
manager.setMaxNotificationAttempts(maxAttempts);
}
} catch (final NumberFormatException nfe) {
defaultLogger.error("Maximum number of attempts to send notification email is set to an invalid value of {}; will use default value", attemptProp);
}
}
// 获取 notification.services.file 通知服务的配置文件名称
final String notificationServicesXmlFilename = properties.getProperty(NOTIFICATION_SERVICES_FILE_PROP);
if (notificationServicesXmlFilename == null) {
defaultLogger.info("No Bootstrap Notification Services configured.");
return manager;
}
// 解析通知服务的xml配置文件
final File xmlFile = new File(notificationServicesXmlFilename);
final File servicesFile;
if (xmlFile.isAbsolute()) {
servicesFile = xmlFile;
} else {
final File confDir = bootstrapConfigFile.getParentFile();
final File nifiHome = confDir.getParentFile();
servicesFile = new File(nifiHome, notificationServicesXmlFilename);
}
if (!servicesFile.exists()) {
defaultLogger.error("Bootstrap Notification Services file configured as " + servicesFile + " but could not find file; will not load notification services");
return manager;
}
try {
// 装载通知服务配置
manager.loadNotificationServices(servicesFile);
} catch (final Exception e) {
defaultLogger.error("Bootstrap Notification Services file configured as " + servicesFile + " but failed to load notification services", e);
}
// 注册 start stop dead 的通知服务
registerNotificationServices(manager, NotificationType.NIFI_STARTED, properties.getProperty(NIFI_START_NOTIFICATION_SERVICE_IDS_PROP));
registerNotificationServices(manager, NotificationType.NIFI_STOPPED, properties.getProperty(NIFI_STOP_NOTIFICATION_SERVICE_IDS_PROP));
registerNotificationServices(manager, NotificationType.NIFI_DIED, properties.getProperty(NIFI_DEAD_NOTIFICATION_SERVICE_IDS_PROP));
return manager;
}
/*
* 注册通知服务
**/
private void registerNotificationServices(final NotificationServiceManager manager, final NotificationType type, final String serviceIds) {
if (serviceIds == null) {
defaultLogger.info("Registered no Notification Services for Notification Type {}", type);
return;
}
int registered = 0;
for (final String id : serviceIds.split(",")) {
final String trimmed = id.trim();
if (trimmed.isEmpty()) {
continue;
}
try {
manager.registerNotificationService(type, trimmed);
registered++;
} catch (final Exception e) {
defaultLogger.warn("Failed to register Notification Service with ID {} for Notifications of type {} due to {}", trimmed, type, e.toString());
defaultLogger.error("", e);
}
}
defaultLogger.info("Registered {} Notification Services for Notification Type {}", registered, type);
}
/**根据参数，读取相应的文件*/
protected File getBootstrapFile(final Logger logger, String directory, String defaultDirectory, String fileName) throws IOException {
final File confDir = bootstrapConfigFile.getParentFile();
final File nifiHome = confDir.getParentFile();
String confFileDir = System.getProperty(directory);
final File fileDir;
if (confFileDir != null) {
fileDir = new File(confFileDir.trim());
} else {
fileDir = new File(nifiHome, defaultDirectory);
}
FileUtils.ensureDirectoryExistAndCanAccess(fileDir);
final File statusFile = new File(fileDir, fileName);
logger.debug("Status File: {}", statusFile);
return statusFile;
}
/**读取run目录下nifi.pid文件*/
protected File getPidFile(final Logger logger) throws IOException {
return getBootstrapFile(logger, NIFI_PID_DIR_PROP, DEFAULT_PID_DIR, NIFI_PID_FILE_NAME);
}
/**读取run目录下nifi.status文件*/
protected File getStatusFile(final Logger logger) throws IOException {
return getBootstrapFile(logger, NIFI_PID_DIR_PROP, DEFAULT_PID_DIR, NIFI_STATUS_FILE_NAME);
}
/**读取run目录下nifi.lock文件*/
protected File getLockFile(final Logger logger) throws IOException {
return getBootstrapFile(logger, NIFI_PID_DIR_PROP, DEFAULT_PID_DIR, NIFI_LOCK_FILE_NAME);
}
protected File getStatusFile() throws IOException {
return getStatusFile(defaultLogger);
}
/**loadrun目录下nifi.status文件内容*/
private Properties loadProperties(final Logger logger) throws IOException {
final Properties props = new Properties();
final File statusFile = getStatusFile(logger);
if (statusFile == null || !statusFile.exists()) {
logger.debug("No status file to load properties from");
return props;
}
try (final FileInputStream fis = new FileInputStream(getStatusFile(logger))) {
props.load(fis);
}
final Map<Object, Object> modified = new HashMap<>(props);
modified.remove("secret.key");
logger.debug("Properties: {}", modified);
return props;
}
/**
* 将获取到的pid值写入run目录下的nifi.pid nifi.status文件中
*/
private synchronized void savePidProperties(final Properties pidProperties, final Logger logger) throws IOException {
final String pid = pidProperties.getProperty(PID_KEY);
if (!StringUtils.isBlank(pid)) {
writePidFile(pid, logger);
}
final File statusFile = getStatusFile(logger);
if (statusFile.exists() && !statusFile.delete()) {
logger.warn("Failed to delete {}", statusFile);
}
if (!statusFile.createNewFile()) {
throw new IOException("Failed to create file " + statusFile);
}
try {
final Set<PosixFilePermission> perms = new HashSet<>();
perms.add(PosixFilePermission.OWNER_READ);
perms.add(PosixFilePermission.OWNER_WRITE);
Files.setPosixFilePermissions(statusFile.toPath(), perms);
} catch (final Exception e) {
logger.warn("Failed to set permissions so that only the owner can read status file {}; "
+ "this may allows others to have access to the key needed to communicate with NiFi. "
+ "Permissions should be changed so that only the owner can read this file", statusFile);
}
try (final FileOutputStream fos = new FileOutputStream(statusFile)) {
pidProperties.store(fos, null);
fos.getFD().sync();
}
logger.debug("Saved Properties {} to {}", new Object[]{pidProperties, statusFile});
} /**
* 将获取到的pid值写入run目录下的nifi.pid文件中
*/
private synchronized void writePidFile(final String pid, final Logger logger) throws IOException {
final File pidFile = getPidFile(logger);
if (pidFile.exists() && !pidFile.delete()) {
logger.warn("Failed to delete {}", pidFile);
}
if (!pidFile.createNewFile()) {
throw new IOException("Failed to create file " + pidFile);
}
try {
final Set<PosixFilePermission> perms = new HashSet<>();
perms.add(PosixFilePermission.OWNER_WRITE);
perms.add(PosixFilePermission.OWNER_READ);
perms.add(PosixFilePermission.GROUP_READ);
perms.add(PosixFilePermission.OTHERS_READ);
Files.setPosixFilePermissions(pidFile.toPath(), perms);
} catch (final Exception e) {
logger.warn("Failed to set permissions so that only the owner can read pid file {}; "
+ "this may allows others to have access to the key needed to communicate with NiFi. "
+ "Permissions should be changed so that only the owner can read this file", pidFile);
}
try (final FileOutputStream fos = new FileOutputStream(pidFile)) {
fos.write(pid.getBytes(StandardCharsets.UTF_8));
fos.getFD().sync();
}
logger.debug("Saved Pid {} to {}", new Object[]{pid, pidFile});
}
private boolean isPingSuccessful(final int port, final String secretKey, final Logger logger) {
logger.debug("Pinging {}", port);
try (final Socket socket = new Socket("localhost", port)) {
final OutputStream out = socket.getOutputStream();
out.write((PING_CMD + " " + secretKey + "n").getBytes(StandardCharsets.UTF_8));
out.flush();
logger.debug("Sent PING command");
socket.setSoTimeout(5000);
final InputStream in = socket.getInputStream();
final BufferedReader reader = new BufferedReader(new InputStreamReader(in));
final String response = reader.readLine();
logger.debug("PING response: {}", response);
out.close();
reader.close();
return PING_CMD.equals(response);
} catch (final IOException ioe) {
return false;
}
}
/**
*读取run目录下 nifi.status 返回其中port值
*nifi.status中的值是每次执行RunNIFI.start后写进去的，stop后清除
*/
private Integer getCurrentPort(final Logger logger) throws IOException {
final Properties props = loadProperties(logger);
final String portVal = props.getProperty("port");
if (portVal == null) {
logger.debug("No Port found in status file");
return null;
} else {
logger.debug("Port defined in status file: {}", portVal);
}
final int port = Integer.parseInt(portVal);
final boolean success = isPingSuccessful(port, props.getProperty("secret.key"), logger);
if (success) {
logger.debug("Successful PING on port {}", port);
return port;
}
final String pid = props.getProperty(PID_KEY);
logger.debug("PID in status file is {}", pid);
if (pid != null) {
final boolean procRunning = isProcessRunning(pid, logger);
if (procRunning) {
return port;
} else {
return null;
}
}
return null;
}
private boolean isProcessRunning(final String pid, final Logger logger) {
try {
// We use the "ps" command to check if the process is still running.
final ProcessBuilder builder = new ProcessBuilder();
builder.command("ps", "-p", pid);
final Process proc = builder.start();
// Look for the pid in the output of the 'ps' command.
boolean running = false;
String line;
try (final InputStream in = proc.getInputStream();
final Reader streamReader = new InputStreamReader(in);
final BufferedReader reader = new BufferedReader(streamReader)) {
while ((line = reader.readLine()) != null) {
if (line.trim().startsWith(pid)) {
running = true;
}
}
}
// If output of the ps command had our PID, the process is running.
if (running) {
logger.debug("Process with PID {} is running", pid);
} else {
logger.debug("Process with PID {} is not running", pid);
}
return running;
} catch (final IOException ioe) {
System.err.println("Failed to determine if Process " + pid + " is running; assuming that it is not");
return false;
}
}
private Status getStatus(final Logger logger) {
final Properties props;
try {
props = loadProperties(logger);
} catch (final IOException ioe) {
return new Status(null, null, false, false);
}
if (props == null) {
return new Status(null, null, false, false);
}
final String portValue = props.getProperty("port");
final String pid = props.getProperty(PID_KEY);
final String secretKey = props.getProperty("secret.key");
if (portValue == null && pid == null) {
return new Status(null, null, false, false);
}
Integer port = null;
boolean pingSuccess = false;
if (portValue != null) {
try {
port = Integer.parseInt(portValue);
pingSuccess = isPingSuccessful(port, secretKey, logger);
} catch (final NumberFormatException nfe) {
return new Status(null, null, false, false);
}
}
if (pingSuccess) {
return new Status(port, pid, true, true);
}
final boolean alive = pid != null && isProcessRunning(pid, logger);
return new Status(port, pid, pingSuccess, alive);
}
public int status() throws IOException {
final Logger logger = cmdLogger;
final Status status = getStatus(logger);
if (status.isRespondingToPing()) {
logger.info("Apache NiFi is currently running, listening to Bootstrap on port {}, PID={}",
new Object[]{status.getPort(), status.getPid() == null ? "unknown" : status.getPid()});
return 0;
}
if (status.isProcessRunning()) {
logger.info("Apache NiFi is running at PID {} but is not responding to ping requests", status.getPid());
return 4;
}
if (status.getPort() == null) {
logger.info("Apache NiFi is not running");
return 3;
}
if (status.getPid() == null) {
logger.info("Apache NiFi is not responding to Ping requests. The process may have died or may be hung");
} else {
logger.info("Apache NiFi is not running");
}
return 3;
}
public void env() {
final Logger logger = cmdLogger;
final Status status = getStatus(logger);
if (status.getPid() == null) {
logger.info("Apache NiFi is not running");
return;
}
final Class<?> virtualMachineClass;
try {
virtualMachineClass = Class.forName("com.sun.tools.attach.VirtualMachine");
} catch (final ClassNotFoundException cnfe) {
logger.error("Seems tools.jar (Linux / Windows JDK) or classes.jar (Mac OS) is not available in classpath");
return;
}
final Method attachMethod;
final Method detachMethod;
try {
attachMethod = virtualMachineClass.getMethod("attach", String.class);
detachMethod = virtualMachineClass.getDeclaredMethod("detach");
} catch (final Exception e) {
logger.error("Methods required for getting environment not available", e);
return;
}
final Object virtualMachine;
try {
virtualMachine = attachMethod.invoke(null, status.getPid());
} catch (final Throwable t) {
logger.error("Problem attaching to NiFi", t);
return;
}
try {
final Method getSystemPropertiesMethod = virtualMachine.getClass().getMethod("getSystemProperties");
final Properties sysProps = (Properties) getSystemPropertiesMethod.invoke(virtualMachine);
for (Entry<Object, Object> syspropEntry : sysProps.entrySet()) {
logger.info(syspropEntry.getKey().toString() + " = " + syspropEntry.getValue().toString());
}
} catch (Throwable t) {
throw new RuntimeException(t);
} finally {
try {
detachMethod.invoke(virtualMachine);
} catch (final Exception e) {
logger.warn("Caught exception detaching from process", e);
}
}
}
/**
* 将NiFi线程dump写入给定文件;如果文件为空，则记录在INFO级别。
*
* @param dumpFile 要将dump内容写入其中的文件
* @throws IOException 如果在编写dump文件时发生任何问题
*/
public void dump(final File dumpFile) throws IOException {
final Logger logger = defaultLogger; // 默认写到nifi-bootstrap.log中
final Integer port = getCurrentPort(logger);
if (port == null) {
logger.info("Apache NiFi is not currently running");
return;
}
final Properties nifiProps = loadProperties(logger);
final String secretKey = nifiProps.getProperty("secret.key");
final StringBuilder sb = new StringBuilder();
try (final Socket socket = new Socket()) {
logger.debug("Connecting to NiFi instance");
socket.setSoTimeout(60000);
socket.connect(new InetSocketAddress("localhost", port));
logger.debug("Established connection to NiFi instance.");
socket.setSoTimeout(60000);
logger.debug("Sending DUMP Command to port {}", port);
final OutputStream out = socket.getOutputStream();
out.write((DUMP_CMD + " " + secretKey + "n").getBytes(StandardCharsets.UTF_8));
out.flush();
final InputStream in = socket.getInputStream();
try (final BufferedReader reader = new BufferedReader(new InputStreamReader(in))) {
String line;
while ((line = reader.readLine()) != null) {
sb.append(line).append("n");
}
}
}
final String dump = sb.toString();
if (dumpFile == null) {
logger.info(dump);
} else {
try (final FileOutputStream fos = new FileOutputStream(dumpFile)) {
fos.write(dump.getBytes(StandardCharsets.UTF_8));
}
// 我们希望(默认情况下)登录到将线程转储写入指定文件的控制台
cmdLogger.info("Successfully wrote thread dump to {}", dumpFile.getAbsolutePath());
}
}
/** nifi stop 通知*/
public void notifyStop() {
final String hostname = getHostname();
final SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss.SSS");
final String now = sdf.format(System.currentTimeMillis());
String user = System.getProperty("user.name");
if (user == null || user.trim().isEmpty()) {
user = "Unknown User";
}
serviceManager.notify(NotificationType.NIFI_STOPPED, "NiFi Stopped on Host " + hostname,
"Hello,nnApache NiFi has been told to initiate a shutdown on host " + hostname + " at " + now + " by user " + user);
}
/** nifi stop 命令*/
public void stop() throws IOException {
final Logger logger = cmdLogger;
final Integer port = getCurrentPort(logger);
if (port == null) {
logger.info("Apache NiFi is not currently running");
return;
}
// 指示正在执行停止命令
final File lockFile = getLockFile(logger);
if (!lockFile.exists()) {
lockFile.createNewFile();
}
final Properties nifiProps = loadProperties(logger);
final String secretKey = nifiProps.getProperty("secret.key");
final String pid = nifiProps.getProperty(PID_KEY);
final File statusFile = getStatusFile(logger);
final File pidFile = getPidFile(logger);
try (final Socket socket = new Socket()) {
logger.debug("Connecting to NiFi instance");
socket.setSoTimeout(10000);
socket.connect(new InetSocketAddress("localhost", port));
logger.debug("Established connection to NiFi instance.");
socket.setSoTimeout(10000);
// BootstrapListener 监听接受命令 进行nifi关闭动作
logger.debug("Sending SHUTDOWN Command to port {}", port);
final OutputStream out = socket.getOutputStream();
out.write((SHUTDOWN_CMD + " " + secretKey + "n").getBytes(StandardCharsets.UTF_8));
out.flush();
socket.shutdownOutput();
final InputStream in = socket.getInputStream();
int lastChar;
final StringBuilder sb = new StringBuilder();
while ((lastChar = in.read()) > -1) {
sb.append((char) lastChar);
}
final String response = sb.toString().trim();
logger.debug("Received response to SHUTDOWN command: {}", response);
if (SHUTDOWN_CMD.equals(response)) {
logger.info("Apache NiFi has accepted the Shutdown Command and is shutting down now");
if (pid != null) {
final Properties bootstrapProperties = new Properties();
try (final FileInputStream fis = new FileInputStream(bootstrapConfigFile)) {
bootstrapProperties.load(fis);
}
String gracefulShutdown = bootstrapProperties.getProperty(GRACEFUL_SHUTDOWN_PROP, DEFAULT_GRACEFUL_SHUTDOWN_VALUE);
int gracefulShutdownSeconds;
try {
gracefulShutdownSeconds = Integer.parseInt(gracefulShutdown);
} catch (final NumberFormatException nfe) {
gracefulShutdownSeconds = Integer.parseInt(DEFAULT_GRACEFUL_SHUTDOWN_VALUE);
}
notifyStop();
final long startWait = System.nanoTime();
while (isProcessRunning(pid, logger)) {
logger.info("Waiting for Apache NiFi to finish shutting down...");
final long waitNanos = System.nanoTime() - startWait;
final long waitSeconds = TimeUnit.NANOSECONDS.toSeconds(waitNanos);
if (waitSeconds >= gracefulShutdownSeconds && gracefulShutdownSeconds > 0) {
if (isProcessRunning(pid, logger)) {
logger.warn("NiFi has not finished shutting down after {} seconds. Killing process.", gracefulShutdownSeconds);
try {
killProcessTree(pid, logger);
} catch (final IOException ioe) {
logger.error("Failed to kill Process with PID {}", pid);
}
}
break;
} else {
try {
Thread.sleep(2000L);
} catch (final InterruptedException ie) {
}
}
}
if (statusFile.exists() && !statusFile.delete()) {
logger.error("Failed to delete status file {}; this file should be cleaned up manually", statusFile);
}
if (pidFile.exists() && !pidFile.delete()) {
logger.error("Failed to delete pid file {}; this file should be cleaned up manually", pidFile);
}
logger.info("NiFi has finished shutting down.");
}
} else {
logger.error("When sending SHUTDOWN command to NiFi, got unexpected response {}", response);
}
} catch (final IOException ioe) {
if (pid == null) {
logger.error("Failed to send shutdown command to port {} due to {}. No PID found for the NiFi process, so unable to kill process; "
+ "the process should be killed manually.", new Object[]{port, ioe.toString()});
} else {
logger.error("Failed to send shutdown command to port {} due to {}. Will kill the NiFi Process with PID {}.", port, ioe.toString(), pid);
notifyStop();
killProcessTree(pid, logger);
if (statusFile.exists() && !statusFile.delete()) {
logger.error("Failed to delete status file {}; this file should be cleaned up manually", statusFile);
}
}
} finally {
if (lockFile.exists() && !lockFile.delete()) {
logger.error("Failed to delete lock file {}; this file should be cleaned up manually", lockFile);
}
}
} /**获取当前进程的子进程*/
private static List<String> getChildProcesses(final String ppid) throws IOException {
final Process proc = Runtime.getRuntime().exec(new String[]{"ps", "-o", "pid", "--no-headers", "--ppid", ppid});
final List<String> childPids = new ArrayList<>();
try (final InputStream in = proc.getInputStream();
final BufferedReader reader = new BufferedReader(new InputStreamReader(in))) {
String line;
while ((line = reader.readLine()) != null) {
childPids.add(line.trim());
}
}
return childPids;
}
/**kill -9 全部杀死*/
private void killProcessTree(final String pid, final Logger logger) throws IOException {
logger.debug("Killing Process Tree for PID {}", pid);
final List<String> children = getChildProcesses(pid);
logger.debug("Children of PID {}: {}", new Object[]{pid, children});
for (final String childPid : children) {
killProcessTree(childPid, logger);
}
// 直接kill -9 全部杀死
Runtime.getRuntime().exec(new String[]{"kill", "-9", pid});
}
/**判断进程是否在运行*/
public static boolean isAlive(final Process process) {
try {
process.exitValue();
return false;
} catch (final IllegalStateException | IllegalThreadStateException itse) {
return true;
}
}
/**获取本机地址 */
private String getHostname() {
String hostname = "Unknown Host";
String ip = "Unknown IP Address";
try {
final InetAddress localhost = InetAddress.getLocalHost();
hostname = localhost.getHostName();
ip = localhost.getHostAddress();
} catch (final Exception e) {
defaultLogger.warn("Failed to obtain hostname for notification due to:", e);
}
return hostname + " (" + ip + ")";
}
/**nifi.sh start 命令*/
@SuppressWarnings({"rawtypes", "unchecked"})
public void start() throws IOException, InterruptedException {
// 读取run目录下的nifi.status文件 查看port是否有值 有值说明当前nifi正在运行中
final Integer port = getCurrentPort(cmdLogger);
if (port != null) {
cmdLogger.info("Apache NiFi is already running, listening to Bootstrap on port " + port);
return;
}
// 查找run目录下nifi.lock文件 如果存在 则尝试删除 删除失败则发出警告
final File prevLockFile = getLockFile(cmdLogger);
if (prevLockFile.exists() && !prevLockFile.delete()) {
cmdLogger.warn("Failed to delete previous lock file {}; this file should be cleaned up manually", prevLockFile);
}
// 作启动进程使用
final ProcessBuilder builder = new ProcessBuilder();
if (!bootstrapConfigFile.exists()) {
throw new FileNotFoundException(bootstrapConfigFile.getAbsolutePath());
}
// load bootstratp.conf 文件
final Properties properties = new Properties();
try (final FileInputStream fis = new FileInputStream(bootstrapConfigFile)) {
properties.load(fis);
}
//bootstrap.con的配置 转map 作启动下一个进程的启动参数
final Map<String, String> props = new HashMap<>();
props.putAll((Map) properties);
//从bootstrap.conf 读取working.dir (默认配置文件里是没有的)
final String specifiedWorkingDir = props.get("working.dir");
if (specifiedWorkingDir != null) {
builder.directory(new File(specifiedWorkingDir));
}
// NiFi-HOME/conf/bootstrap.conf
final File bootstrapConfigAbsoluteFile = bootstrapConfigFile.getAbsoluteFile();
// NiFi-HOME/conf
final File binDir = bootstrapConfigAbsoluteFile.getParentFile();
// NiFi-HOME
final File workingDir = binDir.getParentFile();
if (specifiedWorkingDir == null) {
builder.directory(workingDir);
}
// logs目录
final String nifiLogDir = replaceNull(System.getProperty("org.apache.nifi.bootstrap.config.log.dir"), DEFAULT_LOG_DIR).trim();
// lib.dir=./lib
final String libFilename = replaceNull(props.get("lib.dir"), "./lib").trim();
File libDir = getFile(libFilename, workingDir);
//conf.dir=./conf
final String confFilename = replaceNull(props.get("conf.dir"), "./conf").trim();
File confDir = getFile(confFilename, workingDir);
// 获取nifi配置文件名 默认为 nifi.properties
String nifiPropsFilename = props.get("props.file");
if (nifiPropsFilename == null) {
if (confDir.exists()) {
nifiPropsFilename = new File(confDir, "nifi.properties").getAbsolutePath();
} else {
nifiPropsFilename = DEFAULT_CONFIG_FILE;
}
}
nifiPropsFilename = nifiPropsFilename.trim();
// 组装 java 启动参数 将bootstrap.conf中的java.arg开头的值添加进去
final List<String> javaAdditionalArgs = new ArrayList<>();
for (final Map.Entry<String, String> entry : props.entrySet()) {
final String key = entry.getKey();
final String value = entry.getValue();
if (key.startsWith("java.arg")) {
javaAdditionalArgs.add(value);
}
}
// 将lib目录下的jar包 文件筛选出来
final File[] libFiles = libDir.listFiles(new FilenameFilter() {
@Override
public boolean accept(final File dir, final String filename) {
return filename.toLowerCase().endsWith(".jar");
}
});
if (libFiles == null || libFiles.length == 0) {
throw new RuntimeException("Could not find lib directory at " + libDir.getAbsolutePath());
}
// 列出conf下的配置文件
final File[] confFiles = confDir.listFiles();
if (confFiles == null || confFiles.length == 0) {
throw new RuntimeException("Could not find conf directory at " + confDir.getAbsolutePath());
}
// java classpath(java -cp) 参数列表
final List<String> cpFiles = new ArrayList<>(confFiles.length + libFiles.length);
cpFiles.add(confDir.getAbsolutePath());
for (final File file : libFiles) {
cpFiles.add(file.getAbsolutePath());
}
// list 转 字符串
final StringBuilder classPathBuilder = new StringBuilder();
for (int i = 0; i < cpFiles.size(); i++) {
final String filename = cpFiles.get(i);
classPathBuilder.append(filename);
if (i < cpFiles.size() - 1) {
classPathBuilder.append(File.pathSeparatorChar);
}
}
final String classPath = classPathBuilder.toString();
// java=java
String javaCmd = props.get("java");
if (javaCmd == null) {
javaCmd = DEFAULT_JAVA_CMD;
}
// File.separatorChar 斜杠/
if (javaCmd.equals(DEFAULT_JAVA_CMD)) {
String javaHome = System.getenv("JAVA_HOME");
if (javaHome != null) {
String fileExtension = isWindows() ? ".exe" : "";
File javaFile = new File(javaHome + File.separatorChar + "bin"
+ File.separatorChar + "java" + fileExtension);
if (javaFile.exists() && javaFile.canExecute()) {
javaCmd = javaFile.getAbsolutePath();
}
}
}
//监听RunNIFI进程，内部有一个监听serverSocket，随机了一个端口监听，里面把NIFI进程(RunNiFi启动的)的端口号和pid写进文件
final NiFiListener listener = new NiFiListener();
//这个监听端口作为启动NIFI进程的变量，然后在NIFI进程中向RunNIFI 进行的serverSocket通信，发送数据(NiFi 进程的Port和随机生成的secretKey)
final int listenPort = listener.start(this);
final List<String> cmd = new ArrayList<>();
cmd.add(javaCmd);
cmd.add("-classpath");
cmd.add(classPath);
cmd.addAll(javaAdditionalArgs);
cmd.add("-Dnifi.properties.file.path=" + nifiPropsFilename);
cmd.add("-Dnifi.bootstrap.listen.port=" + listenPort);
cmd.add("-Dapp=NiFi");
cmd.add("-Dorg.apache.nifi.bootstrap.config.log.dir=" + nifiLogDir);
if (!System.getProperty("java.version").startsWith("1.")) {
// running on Java 9+, java.xml.bind module must be made available
cmd.add("--add-modules=java.xml.bind");
}
cmd.add("org.apache.nifi.NiFi");
if (isSensitiveKeyPresent(props)) {
Path sensitiveKeyFile = createSensitiveKeyFile(confDir);
writeSensitiveKeyFile(props, sensitiveKeyFile);
cmd.add("-K " + sensitiveKeyFile.toFile().getAbsolutePath());
}
builder.command(cmd);
final StringBuilder cmdBuilder = new StringBuilder();
for (final String s : cmd) {
cmdBuilder.append(s).append(" ");
}
//控制台输出日志
cmdLogger.info("Starting Apache NiFi...");
cmdLogger.info("Working Directory: {}", workingDir.getAbsolutePath());
cmdLogger.info("Command: {}", cmdBuilder.toString());
// graceful.shutdown.seconds=20 bootstrap.conf中的默认配置 关闭的默认时间
String gracefulShutdown = props.get(GRACEFUL_SHUTDOWN_PROP);
if (gracefulShutdown == null) {
gracefulShutdown = DEFAULT_GRACEFUL_SHUTDOWN_VALUE;
}
final int gracefulShutdownSeconds;
try {
gracefulShutdownSeconds = Integer.parseInt(gracefulShutdown);
} catch (final NumberFormatException nfe) {
throw new NumberFormatException("The '" + GRACEFUL_SHUTDOWN_PROP + "' property in Bootstrap Config File "
+ bootstrapConfigAbsoluteFile.getAbsolutePath() + " has an invalid value. Must be a non-negative integer");
}
if (gracefulShutdownSeconds < 0) {
throw new NumberFormatException("The '" + GRACEFUL_SHUTDOWN_PROP + "' property in Bootstrap Config File "
+ bootstrapConfigAbsoluteFile.getAbsolutePath() + " has an invalid value. Must be a non-negative integer");
}
// 启动进程
Process process = builder.start();
handleLogging(process);
//返回进程在系统中的pid
Long pid = OSUtils.getProcessId(process, cmdLogger);
if (pid == null) {
cmdLogger.warn("Launched Apache NiFi but could not determined the Process ID");
} else {
// 将pid写入run目录下的nifi.pid中
nifiPid = pid;
final Properties pidProperties = new Properties();
pidProperties.setProperty(PID_KEY, String.valueOf(nifiPid));
savePidProperties(pidProperties, cmdLogger);
cmdLogger.info("Launched Apache NiFi with Process ID " + pid);
}
// 实例化 shutdownHook 执行NIFI关闭时的一些操作
shutdownHook = new ShutdownHook(process, this, secretKey, gracefulShutdownSeconds, loggingExecutor);
final Runtime runtime = Runtime.getRuntime();
runtime.addShutdownHook(shutdownHook);
// 获取主机地址
final String hostname = getHostname();
final SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss.SSS");
String now = sdf.format(System.currentTimeMillis());
String user = System.getProperty("user.name");
if (user == null || user.trim().isEmpty()) {
user = "Unknown User";
}
// NIFI 启动通知(如果配置了的话)
serviceManager.notify(NotificationType.NIFI_STARTED, "NiFi Started on Host " + hostname, "Hello,nnApache NiFi has been started on host " + hostname + " at " + now + " by user " + user);
// 循环监听NIFI进程状态 NIFI Died 重启以及通知
while (true) {
final boolean alive = isAlive(process);
// 如果进程还在运行 则继续循环
if (alive) {
try {
Thread.sleep(1000L);
} catch (final InterruptedException ie) {
}
}
// 进程不在运行
else {
try {
runtime.removeShutdownHook(shutdownHook);
} catch (final IllegalStateException ise) {
// 在已经关闭时发生
}
now = sdf.format(System.currentTimeMillis());
// 默认会自动重启 nifi
if (autoRestartNiFi) {
final File statusFile = getStatusFile(defaultLogger);
if (!statusFile.exists()) {
defaultLogger.info("Status File no longer exists. Will not restart NiFi");
return;
}
final File lockFile = getLockFile(defaultLogger);
if (lockFile.exists()) {
defaultLogger.info("A shutdown was initiated. Will not restart NiFi");
return;
}
// 如果nifi之前没有启动过 那么也就没有重启一说
final boolean previouslyStarted = getNifiStarted();
if (!previouslyStarted) {
defaultLogger.info("NiFi never started. Will not restart NiFi");
return;
} else {
//如果到这一步，说明没啥问题，应该执行重启动作，设置NIFI启动状态为false
setNiFiStarted(false);
}
// nifi.bootstrap.sensitive.key 主键为十六进制格式，用于加密的敏感配置值 默认为空
// 否则会在conf下生成sensitive.key文件
if (isSensitiveKeyPresent(props)) {
Path sensitiveKeyFile = createSensitiveKeyFile(confDir);
writeSensitiveKeyFile(props, sensitiveKeyFile);
}
defaultLogger.warn("Apache NiFi appears to have died. Restarting...");
process = builder.start();
handleLogging(process);
pid = OSUtils.getProcessId(process, defaultLogger);
if (pid == null) {
cmdLogger.warn("Launched Apache NiFi but could not obtain the Process ID");
} else {
nifiPid = pid;
final Properties pidProperties = new Properties();
pidProperties.setProperty(PID_KEY, String.valueOf(nifiPid));
savePidProperties(pidProperties, defaultLogger);
cmdLogger.info("Launched Apache NiFi with Process ID " + pid);
}
shutdownHook = new ShutdownHook(process, this, secretKey, gracefulShutdownSeconds, loggingExecutor);
runtime.addShutdownHook(shutdownHook);
//判断预期的时间内 nifi是否启动成功
final boolean started = waitForStart();
if (started) {
defaultLogger.info("Successfully started Apache NiFi{}", (pid == null ? "" : " with PID " + pid));
serviceManager.notify(NotificationType.NIFI_DIED, "NiFi Died on Host " + hostname,
"Hello,nnIt appears that Apache NiFi has died on host " + hostname + " at " + now + "; automatically restarting NiFi");
} else {
defaultLogger.error("Apache NiFi does not appear to have started");
// 我们希望重新启动nifi，因此发送一个通知，说明它已经死亡。如果我们不重新启动nifi，那么这意味着我们故意停止服务。
serviceManager.notify(NotificationType.NIFI_DIED, "NiFi Died on Host " + hostname,
"Hello,nnIt appears that Apache NiFi has died on host " + hostname + " at " + now +
". Attempted to restart NiFi but the services does not appear to have restarted!");
}
} else {
return;
}
}
}
}
/**写sensitive.key值*/
private void writeSensitiveKeyFile(Map<String, String> props, Path sensitiveKeyFile) throws IOException {
BufferedWriter sensitiveKeyWriter = Files.newBufferedWriter(sensitiveKeyFile, StandardCharsets.UTF_8);
sensitiveKeyWriter.write(props.get(NIFI_BOOTSTRAP_SENSITIVE_KEY));
sensitiveKeyWriter.close();
}
/**生成sensitive.key文件*/
private Path createSensitiveKeyFile(File confDir) {
Path sensitiveKeyFile = Paths.get(confDir+"/sensitive.key");
final boolean isPosixSupported = FileSystems.getDefault().supportedFileAttributeViews().contains("posix");
try {
if (isPosixSupported) {
// Initially create file with the empty permission set (so nobody can get a file descriptor on it):
Set<PosixFilePermission> perms = new HashSet<PosixFilePermission>();
FileAttribute<Set<PosixFilePermission>> attr = PosixFilePermissions.asFileAttribute(perms);
sensitiveKeyFile = Files.createFile(sensitiveKeyFile, attr);
// Then, once created, add owner-only rights:
perms.add(PosixFilePermission.OWNER_WRITE);
perms.add(PosixFilePermission.OWNER_READ);
attr = PosixFilePermissions.asFileAttribute(perms);
Files.setPosixFilePermissions(sensitiveKeyFile, perms);
} else {
// If Posix is not supported (e.g. Windows) then create the key file without permission settings.
cmdLogger.info("Current file system does not support Posix, using default permission settings.");
sensitiveKeyFile = Files.createFile(sensitiveKeyFile);
}
} catch (final FileAlreadyExistsException faee) {
cmdLogger.error("The sensitive.key file {} already exists. That shouldn't have been. Aborting.", sensitiveKeyFile);
System.exit(1);
} catch (final Exception e) {
cmdLogger.error("Other failure relating to setting permissions on {}. "
+ "(so that only the owner can read it). "
+ "This is fatal to the bootstrap process for security reasons. Exception was: {}", sensitiveKeyFile, e);
System.exit(1);
}
return sensitiveKeyFile;
}
/**在bootstrap.conf中判断sensitive.key是否配置了*/
private boolean isSensitiveKeyPresent(Map<String, String> props) {
return props.containsKey(NIFI_BOOTSTRAP_SENSITIVE_KEY) && !StringUtils.isBlank(props.get(NIFI_BOOTSTRAP_SENSITIVE_KEY));
}
/**日志*/
private void handleLogging(final Process process) {
final Set<Future<?>> existingFutures = loggingFutures;
if (existingFutures != null) {
for (final Future<?> future : existingFutures) {
future.cancel(false);
}
}
final Future<?> stdOutFuture = loggingExecutor.submit(new Runnable() {
@Override
public void run() {
final Logger stdOutLogger = LoggerFactory.getLogger("org.apache.nifi.StdOut");
final InputStream in = process.getInputStream();
try (final BufferedReader reader = new BufferedReader(new InputStreamReader(in))) {
String line;
while ((line = reader.readLine()) != null) {
stdOutLogger.info(line);
}
} catch (IOException e) {
defaultLogger.error("Failed to read from NiFi's Standard Out stream", e);
}
}
});
final Future<?> stdErrFuture = loggingExecutor.submit(new Runnable() {
@Override
public void run() {
final Logger stdErrLogger = LoggerFactory.getLogger("org.apache.nifi.StdErr");
final InputStream in = process.getErrorStream();
try (final BufferedReader reader = new BufferedReader(new InputStreamReader(in))) {
String line;
while ((line = reader.readLine()) != null) {
stdErrLogger.error(line);
}
} catch (IOException e) {
defaultLogger.error("Failed to read from NiFi's Standard Error stream", e);
}
}
});
final Set<Future<?>> futures = new HashSet<>();
futures.add(stdOutFuture);
futures.add(stdErrFuture);
this.loggingFutures = futures;
}
/**启动脚本中判断了本机系统，并设置到了环境变量当中，判断当前系统是否是windows*/
private boolean isWindows() {
final String osName = System.getProperty("os.name");
return osName != null && osName.toLowerCase().contains("win");
}
/**启动等待*/
private boolean waitForStart() {
lock.lock();
try {
final long startTime = System.nanoTime();
//ccPort NiFiCommandControlPort 启动前值为-1，由NiFiListener再次进行设置 1-65535
while (ccPort < 1) {
try {
startupCondition.await(1, TimeUnit.SECONDS);
} catch (final InterruptedException ie) {
return false;
}
final long waitNanos = System.nanoTime() - startTime;
final long waitSeconds = TimeUnit.NANOSECONDS.toSeconds(waitNanos);
if (waitSeconds > STARTUP_WAIT_SECONDS) {
return false;
}
}
} finally {
lock.unlock();
}
return true;
}
private File getFile(final String filename, final File workingDir) {
File file = new File(filename);
if (!file.isAbsolute()) {
file = new File(workingDir, filename);
}
return file;
}
private String replaceNull(final String value, final String replacement) {
return (value == null) ? replacement : value;
}
void setAutoRestartNiFi(final boolean restart) {
this.autoRestartNiFi = restart;
}
/**NiFiListener 调用BootstrapCodec的communicate方法，中再调用次方法，设置ccport并 写入nifi.status文件中*/
void setNiFiCommandControlPort(final int port, final String secretKey) throws IOException {
this.ccPort = port;
this.secretKey = secretKey;
if (shutdownHook != null) {
shutdownHook.setSecretKey(secretKey);
}
final File statusFile = getStatusFile(defaultLogger);
final Properties nifiProps = new Properties();
if (nifiPid != -1) {
nifiProps.setProperty(PID_KEY, String.valueOf(nifiPid));
}
nifiProps.setProperty("port", String.valueOf(ccPort));
nifiProps.setProperty("secret.key", secretKey);
try {
savePidProperties(nifiProps, defaultLogger);
} catch (final IOException ioe) {
defaultLogger.warn("Apache NiFi has started but failed to persist NiFi Port information to {} due to {}", new Object[]{statusFile.getAbsolutePath(), ioe});
}
defaultLogger.info("Apache NiFi now running and listening for Bootstrap requests on port {}", port);
}
int getNiFiCommandControlPort() {
return this.ccPort;
}
void setNiFiStarted(final boolean nifiStarted) {
startedLock.lock();
try {
this.nifiStarted = nifiStarted;
} finally {
startedLock.unlock();
}
}
boolean getNifiStarted() {
startedLock.lock();
try {
return nifiStarted;
} finally {
startedLock.unlock();
}
}
private static class Status {
private final Integer port;
private final String pid;
private final Boolean respondingToPing;
private final Boolean processRunning;
public Status(final Integer port, final String pid, final Boolean respondingToPing, final Boolean processRunning) {
this.port = port;
this.pid = pid;
this.respondingToPing = respondingToPing;
this.processRunning = processRunning;
}
public String getPid() {
return pid;
}
public Integer getPort() {
return port;
}
public boolean isRespondingToPing() {
return Boolean.TRUE.equals(respondingToPing);
}
public boolean isProcessRunning() {
return Boolean.TRUE.equals(processRunning);
}
}
}
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