You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
89 lines
2.3 KiB
89 lines
2.3 KiB
// Copyright 2014 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. |
|
|
|
package google |
|
|
|
import ( |
|
"sort" |
|
"strings" |
|
"sync" |
|
"time" |
|
|
|
"golang.org/x/net/context" |
|
"golang.org/x/oauth2" |
|
) |
|
|
|
// appengineFlex is set at init time by appengineflex_hook.go. If true, we are on App Engine Flex. |
|
var appengineFlex bool |
|
|
|
// Set at init time by appengine_hook.go. If nil, we're not on App Engine. |
|
var appengineTokenFunc func(c context.Context, scopes ...string) (token string, expiry time.Time, err error) |
|
|
|
// Set at init time by appengine_hook.go. If nil, we're not on App Engine. |
|
var appengineAppIDFunc func(c context.Context) string |
|
|
|
// AppEngineTokenSource returns a token source that fetches tokens |
|
// issued to the current App Engine application's service account. |
|
// If you are implementing a 3-legged OAuth 2.0 flow on App Engine |
|
// that involves user accounts, see oauth2.Config instead. |
|
// |
|
// The provided context must have come from appengine.NewContext. |
|
func AppEngineTokenSource(ctx context.Context, scope ...string) oauth2.TokenSource { |
|
if appengineTokenFunc == nil { |
|
panic("google: AppEngineTokenSource can only be used on App Engine.") |
|
} |
|
scopes := append([]string{}, scope...) |
|
sort.Strings(scopes) |
|
return &appEngineTokenSource{ |
|
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 appEngineTokenSource struct { |
|
ctx context.Context |
|
scopes []string |
|
key string // to aeTokens map; space-separated scopes |
|
} |
|
|
|
func (ts *appEngineTokenSource) Token() (*oauth2.Token, error) { |
|
if appengineTokenFunc == nil { |
|
panic("google: AppEngineTokenSource can only be used on App Engine.") |
|
} |
|
|
|
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 |
|
}
|
|
|