feat: adaptation for gRPC

Author: saicaca

pkg/adapters/grpc/traffic.go

@@ -0,0 +1,75 @@
+package grpc
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"github.com/alibaba/sentinel-golang/core/route"
+	"github.com/alibaba/sentinel-golang/core/route/base"
+	"google.golang.org/grpc"
+	"net"
+	"strings"
+)
+
+var (
+	connToBaggage map[string]map[string]string = make(map[string]map[string]string)
+	cm            *route.ClusterManager        = nil
+)
+
+type Baggage map[string]string
+
+func NewDialer(b Baggage) func(context.Context, string) (net.Conn, error) {
+	return func(ctx context.Context, addr string) (net.Conn, error) {
+		parts := strings.Split(addr, "/")
+		if len(parts) != 2 {
+			return nil, errors.New("invalid address format")
+		}
+		tc := &base.TrafficContext{
+			ServiceName: parts[0],
+			MethodName:  parts[1],
+			Headers:     make(map[string]string),
+		}
+
+		instance, err := cm.GetOne(tc)
+
+		if err != nil {
+			return nil, err
+		}
+		if instance == nil {
+			return nil, errors.New("no matched provider")
+		}
+		conn, err := net.Dial("tcp", fmt.Sprintf("%s:%v", instance.Host, instance.Port))
+		if err != nil {
+			return nil, err
+		}
+		b = tc.Baggage
+
+		return conn, nil
+	}
+}
+
+func NewTrafficUnaryIntercepter(baggage Baggage) grpc.DialOption {
+	return grpc.WithUnaryInterceptor(
+		func(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
+			newCtx := ctx
+			// TODO modify the request with baggage
+			return invoker(newCtx, method, req, reply, cc, opts...)
+		})
+}
+
+func NewTrafficStreamIntercepter(baggage Baggage) grpc.DialOption {
+	return grpc.WithStreamInterceptor(
+		func(ctx context.Context, desc *grpc.StreamDesc, cc *grpc.ClientConn, method string, streamer grpc.Streamer, opts ...grpc.CallOption) (grpc.ClientStream, error) {
+			newCtx := ctx
+			// TODO modify the request with baggage
+			return streamer(newCtx, desc, cc, method, opts...)
+		})
+}
+
+func Dial(addr string, opts ...grpc.DialOption) (*grpc.ClientConn, error) {
+	var b Baggage = make(map[string]string)
+	opts = append(opts, grpc.WithContextDialer(NewDialer(b)))
+	opts = append(opts, NewTrafficUnaryIntercepter(b))
+	opts = append(opts, NewTrafficStreamIntercepter(b))
+	return grpc.Dial(addr, opts...)
+}