启动流程：
Main函数参数： server -f graylog.conf.example
主要框架：com.github.rvesse.airline，主要将shell命令参数和java类绑定，根据传参获取对应类的实例，final Runnable command = cli.parse(args);
然后启动实例,由于启动参数是sever，绑定的类是org.graylog2.commands.server
[i]启动server实例
Server类层级如下：
运行run启动该实例，run的逻辑如下
初始化日志
//初始化日志 默认是info
final Level logLevel = setupLogger();
获取plug module，主要有三个
获取config module, 有14个。
//初始化pid文件及netty io.netty.native.workdir配置
获取config module
获取config module ,其实就是所有的配置类添加NamedConfigParametersModule容器
创建上下文
系统自动注入上面获取的plugn module 和 config module, 使用的是google的guice 依赖注入框架。框架具体看我的博客：
依赖注入的类实在是太多，看来项目复杂度还不小，以后有时间可以仔细看看注入的类。
Guice常见上下文，也就是injector容器，创建所有入住类的实例，并保存在injector,后面需要实例，直接可以通过injector获取
GenericInitializerBindings
启动jmx
启动jmxreporter 暴露服务运行metrics， metrics主要使用了
com.codahale.metrics;
启动service
这个地方使用了google的Guava Service框架，这个框架到处都用，个人觉得是java常用组件的升级版本。
具体代码如下
@Override
protected void startCommand() {
final AuditEventSender auditEventSender = injector.getInstance(AuditEventSender.class);
final NodeId nodeId = injector.getInstance(NodeId.class);
final String systemInformation = Tools.getSystemInformation();
final Map<String, Object> auditEventContext = ImmutableMap.of(
"version", version.toString(),
"java", systemInformation,
"node_id", nodeId.toString()
);
auditEventSender.success(AuditActor.system(nodeId), NODE_STARTUP_INITIATE, auditEventContext);
//获取操作系统参数
final OS os = OS.getOs();
final ServerStatus serverStatus = injector.getInstance(ServerStatus.class);
//初始化server状态为starting
serverStatus.initialize();
//
startNodeRegistration(injector);
final ActivityWriter activityWriter;
final ServiceManager serviceManager;
try {
activityWriter = injector.getInstance(ActivityWriter.class);
serviceManager = injector.getInstance(ServiceManager.class);
} catch (ProvisionException e) {
LOG.error("Guice error", e);
annotateProvisionException(e);
auditEventSender.failure(AuditActor.system(nodeId), NODE_STARTUP_INITIATE, auditEventContext);
System.exit(-1);
return;
} catch (Exception e) {
LOG.error("Unexpected exception", e);
auditEventSender.failure(AuditActor.system(nodeId), NODE_STARTUP_INITIATE, auditEventContext);
System.exit(-1);
return;
}
Runtime.getRuntime().addShutdownHook(new Thread(injector.getInstance(shutdownHook())));
// propagate default size to input plugins
MessageInput.setDefaultRecvBufferSize(configuration.getUdpRecvBufferSizes());
// Start services.
final ServiceManagerListener serviceManagerListener = injector.getInstance(ServiceManagerListener.class);
serviceManager.addListener(serviceManagerListener);
try {
serviceManager.startAsync().awaitHealthy();
} catch (Exception e) {
try {
serviceManager.stopAsync().awaitStopped(configuration.getShutdownTimeout(), TimeUnit.MILLISECONDS);
} catch (TimeoutException timeoutException) {
LOG.error("Unable to shutdown properly on time. {}", serviceManager.servicesByState());
}
LOG.error("Graylog startup failed. Exiting. Exception was:", e);
auditEventSender.failure(AuditActor.system(nodeId), NODE_STARTUP_INITIATE, auditEventContext);
System.exit(-1);
}
LOG.info("Services started, startup times in ms: {}", serviceManager.startupTimes());
activityWriter.write(new Activity("Started up.", Main.class));
LOG.info("Graylog " + commandName + " up and running.");
auditEventSender.success(AuditActor.system(nodeId), NODE_STARTUP_COMPLETE, auditEventContext);
// Block forever.
try {
Thread.currentThread().join();
} catch (InterruptedException e) {
return;} }
至此，整个server服务完全启动，后面可以分析每个具体service了。