oauth2/google/appengine_gen1.go
Russ Cox 9bb904979d all: go fmt ./...
Make all our package sources use Go 1.17 gofmt format
(adding //go:build lines).

Not strictly necessary but will avoid spurious changes
as files are edited.

Part of //go:build change (#41184).
See https://golang.org/design/draft-gobuild

Change-Id: I22803ea9e936fbb08984a64155302f47e181de27
Reviewed-on: https://go-review.googlesource.com/c/oauth2/+/294420
Trust: Russ Cox <rsc@golang.org>
Trust: Cody Oss <codyoss@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cody Oss <codyoss@google.com>
2021-02-20 00:06:19 +00:00

79 lines
1.6 KiB
Go

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//go:build appengine
// +build appengine
// This file applies to App Engine first generation runtimes (<= Go 1.9).
package google
import (
"context"
"sort"
"strings"
"sync"
"golang.org/x/oauth2"
"google.golang.org/appengine"
)
func init() {
appengineTokenFunc = appengine.AccessToken
appengineAppIDFunc = appengine.AppID
}
// See comment on AppEngineTokenSource in appengine.go.
func appEngineTokenSource(ctx context.Context, scope ...string) oauth2.TokenSource {
scopes := append([]string{}, scope...)
sort.Strings(scopes)
return &gaeTokenSource{
ctx: ctx,
scopes: scopes,
key: strings.Join(scopes, " "),
}
}
// aeTokens helps the fetched tokens to be reused until their expiration.
var (
aeTokensMu sync.Mutex
aeTokens = make(map[string]*tokenLock) // key is space-separated scopes
)
type tokenLock struct {
mu sync.Mutex // guards t; held while fetching or updating t
t *oauth2.Token
}
type gaeTokenSource struct {
ctx context.Context
scopes []string
key string // to aeTokens map; space-separated scopes
}
func (ts *gaeTokenSource) Token() (*oauth2.Token, error) {
aeTokensMu.Lock()
tok, ok := aeTokens[ts.key]
if !ok {
tok = &tokenLock{}
aeTokens[ts.key] = tok
}
aeTokensMu.Unlock()
tok.mu.Lock()
defer tok.mu.Unlock()
if tok.t.Valid() {
return tok.t, nil
}
access, exp, err := appengineTokenFunc(ts.ctx, ts.scopes...)
if err != nil {
return nil, err
}
tok.t = &oauth2.Token{
AccessToken: access,
Expiry: exp,
}
return tok.t, nil
}