Containerd Server学习 Part 2

【编者的话】containerd v1.0.0的源码分析，以docker-containerd --config /var/run/docker/containerd/containerd.toml为入口，看大神们如何组织Go语言代码

分析

程序信号处理

• 位置：cmd/containerd/main.go

...
var (
  signals = make(chan os.Signal, 2048)
  ctx     = log.WithModule(gocontext.Background(), "containerd")
)
done := handleSignals(ctx, signals, serverC)
...
signal.Notify(signals, handledSignals...)

...

<-done
...

初始化服务

• 位置：cmd/containerd/main.go

...
server, err := server.New(ctx, config)
if err != nil {
    return err
}
...

开启debug / metrics / grpc服务

• 位置：cmd/containerd/main.go
• 依赖：
  github.com/docker/go-metrics
  github.com/grpc-ecosystem/go-grpc-prometheus

...
if config.Debug.Address != "" {
    l, err := sys.GetLocalListener(config.Debug.Address, config.Debug.UID, config.Debug.GID)
    if err != nil {
        return errors.Wrapf(err, "failed to get listener for debug endpoint")
    }
    serve(log.WithModule(ctx, "debug"), l, server.ServeDebug)
}

if config.Metrics.Address != "" {
    l, err := net.Listen("tcp", config.Metrics.Address)
    if err != nil {
        return errors.Wrapf(err, "failed to get listener for metrics endpoint")
    }
    serve(log.WithModule(ctx, "metrics"), l, server.ServeMetrics)
}
l, err := sys.GetLocalListener(address, config.GRPC.UID, config.GRPC.GID)
if err != nil {
    return errors.Wrapf(err, "failed to get listener for main endpoint")
}
serve(log.WithModule(ctx, "grpc"), l, server.ServeGRPC)
...

containerd架构

初始化服务解析

载入插件

• 位置：server/server.go

plugins, err := loadPlugins(config)
if err != nil {
  return nil, err
}

初始化 grpc服务 和 传输服务

• 位置：server/server.go

type Server struct {
    rpc    *grpc.Server
    events *exchange.Exchange
}

grpc服务

• 位置：server/server.go
• 依赖：
  google.golang.org/grpc
  github.com/grpc-ecosystem/go-grpc-prometheus

rpc := grpc.NewServer(
    grpc.UnaryInterceptor(interceptor),
    grpc.StreamInterceptor(grpc_prometheus.StreamServerInterceptor),
)

传输服务

• 位置：events/exchange/exchange.go
• 作用：负责传播事件
• 依赖：github.com/docker/go-events

// Exchange broadcasts events
type Exchange struct {
    broadcaster *goevents.Broadcaster
}

整理：

github.com/llitfkitfk/containerd/tree/part-2