Vendor dependencies for GCS

vendor/cloud.google.com/go/bigtable/internal/option/option.go

@@ -0,0 +1,48 @@
+/*
+Copyright 2015 Google Inc. All Rights Reserved.
+
+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
+
+    http://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 option contains common code for dealing with client options.
+package option
+
+import (
+	"fmt"
+	"os"
+
+	"google.golang.org/api/option"
+	"google.golang.org/grpc"
+)
+
+// DefaultClientOptions returns the default client options to use for the
+// client's gRPC connection.
+func DefaultClientOptions(endpoint, scope, userAgent string) ([]option.ClientOption, error) {
+	var o []option.ClientOption
+	// Check the environment variables for the bigtable emulator.
+	// Dial it directly and don't pass any credentials.
+	if addr := os.Getenv("BIGTABLE_EMULATOR_HOST"); addr != "" {
+		conn, err := grpc.Dial(addr, grpc.WithInsecure())
+		if err != nil {
+			return nil, fmt.Errorf("emulator grpc.Dial: %v", err)
+		}
+		o = []option.ClientOption{option.WithGRPCConn(conn)}
+	} else {
+		o = []option.ClientOption{
+			option.WithEndpoint(endpoint),
+			option.WithScopes(scope),
+			option.WithUserAgent(userAgent),
+		}
+	}
+	return o, nil
+}