chore: migrate to gitea

vendor/github.com/google/s2a-go/internal/handshaker/service/service.go

@@ -0,0 +1,66 @@
+/*
+ *
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package service is a utility for calling the S2A handshaker service.
+package service
+
+import (
+	"context"
+	"sync"
+
+	grpc "google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/credentials/insecure"
+)
+
+var (
+	// mu guards hsConnMap and hsDialer.
+	mu sync.Mutex
+	// hsConnMap represents a mapping from an S2A handshaker service address
+	// to a corresponding connection to an S2A handshaker service instance.
+	hsConnMap = make(map[string]*grpc.ClientConn)
+	// hsDialer will be reassigned in tests.
+	hsDialer = grpc.DialContext
+)
+
+// Dial dials the S2A handshaker service. If a connection has already been
+// established, this function returns it. Otherwise, a new connection is
+// created.
+func Dial(ctx context.Context, handshakerServiceAddress string, transportCreds credentials.TransportCredentials) (*grpc.ClientConn, error) {
+	mu.Lock()
+	defer mu.Unlock()
+
+	hsConn, ok := hsConnMap[handshakerServiceAddress]
+	if !ok {
+		// Create a new connection to the S2A handshaker service. Note that
+		// this connection stays open until the application is closed.
+		var grpcOpts []grpc.DialOption
+		if transportCreds != nil {
+			grpcOpts = append(grpcOpts, grpc.WithTransportCredentials(transportCreds))
+		} else {
+			grpcOpts = append(grpcOpts, grpc.WithTransportCredentials(insecure.NewCredentials()))
+		}
+		var err error
+		hsConn, err = hsDialer(ctx, handshakerServiceAddress, grpcOpts...)
+		if err != nil {
+			return nil, err
+		}
+		hsConnMap[handshakerServiceAddress] = hsConn
+	}
+	return hsConn, nil
+}