rclone/vendor/google.golang.org/api/transport/grpc/dial.go
2017-07-23 08:51:42 +01:00

99 lines
3.3 KiB
Go

// 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 transport/grpc supports network connections to GRPC servers.
// This package is not intended for use by end developers. Use the
// google.golang.org/api/option package to configure API clients.
package transport
import (
"errors"
"fmt"
"golang.org/x/net/context"
"golang.org/x/oauth2/google"
"google.golang.org/api/internal"
"google.golang.org/api/option"
"google.golang.org/grpc"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/credentials/oauth"
)
// Set at init time by dial_appengine.go. If nil, we're not on App Engine.
var appengineDialerHook func(context.Context) grpc.DialOption
// Dial returns a GRPC connection for use communicating with a Google cloud
// service, configured with the given ClientOptions.
func Dial(ctx context.Context, opts ...option.ClientOption) (*grpc.ClientConn, error) {
var o internal.DialSettings
for _, opt := range opts {
opt.Apply(&o)
}
if o.HTTPClient != nil {
return nil, errors.New("unsupported HTTP client specified")
}
if o.GRPCConn != nil {
return o.GRPCConn, nil
}
if o.ServiceAccountJSONFilename != "" {
ts, err := internal.ServiceAcctTokenSource(ctx, o.ServiceAccountJSONFilename, o.Scopes...)
if err != nil {
return nil, err
}
o.TokenSource = ts
}
if o.TokenSource == nil {
var err error
o.TokenSource, err = google.DefaultTokenSource(ctx, o.Scopes...)
if err != nil {
return nil, fmt.Errorf("google.DefaultTokenSource: %v", err)
}
}
grpcOpts := []grpc.DialOption{
grpc.WithPerRPCCredentials(oauth.TokenSource{o.TokenSource}),
grpc.WithTransportCredentials(credentials.NewClientTLSFromCert(nil, "")),
}
if appengineDialerHook != nil {
// Use the Socket API on App Engine.
grpcOpts = append(grpcOpts, appengineDialerHook(ctx))
}
grpcOpts = append(grpcOpts, o.GRPCDialOpts...)
if o.UserAgent != "" {
grpcOpts = append(grpcOpts, grpc.WithUserAgent(o.UserAgent))
}
return grpc.DialContext(ctx, o.Endpoint, grpcOpts...)
}
// DialInsecure returns an insecure GRPC connection for use communicating
// with fake or mock Google cloud service implementations, such as emulators.
// The connection is configured with the given ClientOptions.
func DialInsecure(ctx context.Context, opts ...option.ClientOption) (*grpc.ClientConn, error) {
var o internal.DialSettings
for _, opt := range opts {
opt.Apply(&o)
}
if o.HTTPClient != nil {
return nil, errors.New("unsupported HTTP client specified")
}
if o.GRPCConn != nil {
return o.GRPCConn, nil
}
grpcOpts := []grpc.DialOption{grpc.WithInsecure()}
grpcOpts = append(grpcOpts, o.GRPCDialOpts...)
if o.UserAgent != "" {
grpcOpts = append(grpcOpts, grpc.WithUserAgent(o.UserAgent))
}
return grpc.DialContext(ctx, o.Endpoint, grpcOpts...)
}