containerd的server

services/server/server.go

func New(ctx context.Context, config srvconfig.Config) (Server, error)

for _, p := range plugins {
...
    // check for grpc services that should be registered with the server
    if src, ok := instance.(plugin.Service); ok {
        grpcServices = append(grpcServices, src)
    }
...
}
//注册grpc service
for _, service := range grpcServices {
    if err := service.Register(grpcServer); err != nil {
        return nil, err
    }
}

grpc service列表：

一个典型的service：task service

services/tasks/service.go

func (s *service) Start(ctx context.Context, r *api.StartRequest) (*api.StartResponse, error) {
    return s.local.Start(ctx, r)
}

func (l *local) Start(ctx context.Context, r *api.StartRequest, _ ...grpc.CallOption) (*api.StartResponse, error) {
    t, err := l.getTask(ctx, r.ContainerID)
    if err != nil {
        return nil, err
    }
    // shim的client，v1指向 runtime/v1/linux/process.go
    p := runtime.Process(t)
    if r.ExecID != "" {
        if p, err = t.Process(ctx, r.ExecID); err != nil {
            return nil, errdefs.ToGRPC(err)
        }
    }
    if err := p.Start(ctx); err != nil {
        return nil, errdefs.ToGRPC(err)
    }
    state, err := p.State(ctx)
    if err != nil {
        return nil, errdefs.ToGRPC(err)
    }
    return &api.StartResponse{
        Pid: state.Pid,
    }, nil
}