forked from Mirrors/oauth2
69 lines
1.6 KiB
Go
69 lines
1.6 KiB
Go
// Copyright 2014 The oauth2 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 (
|
|
"errors"
|
|
"sort"
|
|
"strings"
|
|
"sync"
|
|
"time"
|
|
|
|
"golang.org/x/oauth2"
|
|
)
|
|
|
|
var (
|
|
aeTokensMu sync.Mutex // guards aeTokens and appEngineTokenSource.key
|
|
|
|
// aeTokens helps the fetched tokens to be reused until their expiration.
|
|
aeTokens = make(map[string]*tokenLock) // key is '\0'-separated scopes
|
|
)
|
|
|
|
var errInvalidContext = errors.New("oauth2: a valid appengine.Context is required")
|
|
|
|
type tokenLock struct {
|
|
mu sync.Mutex // guards t; held while updating t
|
|
t *oauth2.Token
|
|
}
|
|
|
|
type appEngineTokenSource struct {
|
|
ctx oauth2.Context
|
|
scopes []string
|
|
key string // guarded by package-level mutex, aeTokensMu
|
|
|
|
// fetcherFunc makes the actual RPC to fetch a new access token with an expiry time.
|
|
// Provider of this function is responsible to assert that the given context is valid.
|
|
fetcherFunc func(ctx oauth2.Context, scope ...string) (string, time.Time, error)
|
|
}
|
|
|
|
func (ts *appEngineTokenSource) Token() (*oauth2.Token, error) {
|
|
aeTokensMu.Lock()
|
|
if ts.key == "" {
|
|
sort.Sort(sort.StringSlice(ts.scopes))
|
|
ts.key = strings.Join(ts.scopes, string(0))
|
|
}
|
|
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 != nil && !tok.t.Expired() {
|
|
return tok.t, nil
|
|
}
|
|
access, exp, err := ts.fetcherFunc(ts.ctx, ts.scopes...)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
tok.t = &oauth2.Token{
|
|
AccessToken: access,
|
|
Expiry: exp,
|
|
}
|
|
return tok.t, nil
|
|
}
|