dotcloud/docker

// FIXME(thaJeztah): remove once we are a module; the go:build directive prevents go from downgrading language version to go1.16:
//go:build go1.21

package grpc // import "github.com/docker/docker/api/server/router/grpc"

import (
    "context"
    "fmt"
    "os"
    "strings"

    "github.com/containerd/containerd/defaults"
    "github.com/containerd/log"
    "github.com/docker/docker/api/server/router"
    "github.com/moby/buildkit/util/grpcerrors"
    "github.com/moby/buildkit/util/stack"
    "github.com/moby/buildkit/util/tracing"
    "go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc"
    "go.opentelemetry.io/otel"
    "golang.org/x/net/http2"
    "google.golang.org/grpc"
)

type grpcRouter struct {
    routes     []router.Route
    grpcServer *grpc.Server
    h2Server   *http2.Server
}

// NewRouter initializes a new grpc http router
func NewRouter(backends ...Backend) router.Router {
    opts := []grpc.ServerOption{
        grpc.StatsHandler(tracing.ServerStatsHandler(otelgrpc.WithTracerProvider(otel.GetTracerProvider()))),
        grpc.ChainUnaryInterceptor(unaryInterceptor, grpcerrors.UnaryServerInterceptor),
        grpc.StreamInterceptor(grpcerrors.StreamServerInterceptor),
        grpc.MaxRecvMsgSize(defaults.DefaultMaxRecvMsgSize),
        grpc.MaxSendMsgSize(defaults.DefaultMaxSendMsgSize),
    }

    r := &grpcRouter{
        h2Server:   &http2.Server{},
        grpcServer: grpc.NewServer(opts...),
    }
    for _, b := range backends {
        b.RegisterGRPC(r.grpcServer)
    }
    r.initRoutes()
    return r
}

// Routes returns the available routers to the session controller
func (gr *grpcRouter) Routes() []router.Route {
    return gr.routes
}

func (gr *grpcRouter) initRoutes() {
    gr.routes = []router.Route{
        router.NewPostRoute("/grpc", gr.serveGRPC),
    }
}

func unaryInterceptor(ctx context.Context, req any, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (resp any, err error) {
    // This method is used by the clients to send their traces to buildkit so they can be included
    // in the daemon trace and stored in the build history record. This method can not be traced because
    // it would cause an infinite loop.
    if strings.HasSuffix(info.FullMethod, "opentelemetry.proto.collector.trace.v1.TraceService/Export") {
        return handler(ctx, req)
    }

    resp, err = handler(ctx, req)
    if err != nil {
        log.G(ctx).WithError(err).Error(info.FullMethod)
        if log.GetLevel() >= log.DebugLevel {
            fmt.Fprintf(os.Stderr, "%+v", stack.Formatter(grpcerrors.FromGRPC(err)))
        }
    }
    return resp, err
}