blob: 1905d666949382da9cfe82d2e3ad852bc9e5ea79 [file] [log] [blame]
// Copyright 2017 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 main
import (
"context"
"encoding/json"
"fmt"
"io/ioutil"
"log"
"os"
"os/user"
"path/filepath"
"golang.org/x/oauth2"
"golang.org/x/oauth2/google"
)
var oauthConfig = oauth2.Config{
ClientID: "337869179296-kfjqcm11uodlrj39ifek1adtjjfb0b1p.apps.googleusercontent.com",
ClientSecret: "zOMue3fEEUnz4Em39Ia_-4TN",
Endpoint: google.Endpoint,
Scopes: []string{"https://www.googleapis.com/auth/userinfo.email"},
RedirectURL: "oob",
}
// newTokenSource constructs a token source that will try to read a
// cached token from a file and if missing or invalid will prompt the
// user to refresh it.
func newTokenSource() *tokenReplacer {
// nil token will cause a refresh
tok, _ := readToken()
return &tokenReplacer{tok, oauthConfig.TokenSource(context.Background(), tok), &tokenPrompt{}}
}
// tokenPrompt is a TokenSource that interactively prompts the user
// for a token using copy-paste.
type tokenPrompt struct{}
// Token obtains a new token from the user.
func (*tokenPrompt) Token() (*oauth2.Token, error) {
url := oauthConfig.AuthCodeURL("")
fmt.Fprintf(os.Stderr, "benchsave must authenticate to %s.\n"+
"Note that uploaded files will be publicly recorded with your email address.\n"+
"\n"+
"%s\n"+
"\n"+
"Visit the URL above and enter the auth code: ", *server, url)
var code string
fmt.Scanln(&code)
ctx := context.Background()
return oauthConfig.Exchange(ctx, code)
}
// tokenReplacer is a TokenSource that tries to obtain a token from ts, and if it fails, obtains a token from tsr and uses it to replace ts. New tokens are cached on disk.
type tokenReplacer struct {
lastTok *oauth2.Token
ts, tsr oauth2.TokenSource
}
// Token returns an existing or refreshed token, or uses t.tsr to obtain a new token.
func (t *tokenReplacer) Token() (tok *oauth2.Token, err error) {
defer func() {
// If the AccessToken field changes, cache the new token.
if tok != nil && (t.lastTok == nil || tok.AccessToken != t.lastTok.AccessToken) {
if err := writeToken(tok); err != nil {
log.Printf("cannot cache authentication: %v", err)
}
}
}()
tok, err = t.ts.Token()
if err == nil {
return
}
tok, err = t.tsr.Token()
if err == nil {
t.ts = oauthConfig.TokenSource(context.Background(), tok)
}
return
}
// tokenFilePath returns "$XDG_CONFIG_HOME/.config/benchsave/token.json"
// with recursive expansion of defaults.
func tokenFilePath() string {
d := os.Getenv("XDG_CONFIG_HOME")
if d == "" {
home := os.Getenv("HOME")
if home == "" {
u, err := user.Current()
if err != nil {
log.Fatal(err)
}
home = u.HomeDir
}
d = filepath.Join(home, ".config")
}
return filepath.Join(d, "benchsave", "token.json")
}
// readToken obtains a token from the filesystem.
// If there is no valid token found, it returns a nil token and a reason.
func readToken() (*oauth2.Token, error) {
data, err := ioutil.ReadFile(tokenFilePath())
if err != nil {
return nil, err
}
tok := &oauth2.Token{}
if err := json.Unmarshal(data, tok); err != nil {
return nil, err
}
return tok, nil
}
// writeToken writes the token to the filesystem.
func writeToken(tok *oauth2.Token) (err error) {
p := tokenFilePath()
if err := os.MkdirAll(filepath.Dir(p), 0700); err != nil {
return err
}
data, err := json.Marshal(tok)
if err != nil {
return err
}
return ioutil.WriteFile(p, data, 0600)
}