Vendor main dependencies.

vendor/golang.org/x/oauth2/google/google.go

@@ -0,0 +1,145 @@
+// 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 provides support for making OAuth2 authorized and
+// authenticated HTTP requests to Google APIs.
+// It supports the Web server flow, client-side credentials, service accounts,
+// Google Compute Engine service accounts, and Google App Engine service
+// accounts.
+//
+// For more information, please read
+// https://developers.google.com/accounts/docs/OAuth2
+// and
+// https://developers.google.com/accounts/application-default-credentials.
+package google // import "golang.org/x/oauth2/google"
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/jwt"
+	"google.golang.org/cloud/compute/metadata"
+)
+
+// Endpoint is Google's OAuth 2.0 endpoint.
+var Endpoint = oauth2.Endpoint{
+	AuthURL:  "https://accounts.google.com/o/oauth2/auth",
+	TokenURL: "https://accounts.google.com/o/oauth2/token",
+}
+
+// JWTTokenURL is Google's OAuth 2.0 token URL to use with the JWT flow.
+const JWTTokenURL = "https://accounts.google.com/o/oauth2/token"
+
+// ConfigFromJSON uses a Google Developers Console client_credentials.json
+// file to construct a config.
+// client_credentials.json can be downloadable from https://console.developers.google.com,
+// under "APIs & Auth" > "Credentials". Download the Web application credentials in the
+// JSON format and provide the contents of the file as jsonKey.
+func ConfigFromJSON(jsonKey []byte, scope ...string) (*oauth2.Config, error) {
+	type cred struct {
+		ClientID     string   `json:"client_id"`
+		ClientSecret string   `json:"client_secret"`
+		RedirectURIs []string `json:"redirect_uris"`
+		AuthURI      string   `json:"auth_uri"`
+		TokenURI     string   `json:"token_uri"`
+	}
+	var j struct {
+		Web       *cred `json:"web"`
+		Installed *cred `json:"installed"`
+	}
+	if err := json.Unmarshal(jsonKey, &j); err != nil {
+		return nil, err
+	}
+	var c *cred
+	switch {
+	case j.Web != nil:
+		c = j.Web
+	case j.Installed != nil:
+		c = j.Installed
+	default:
+		return nil, fmt.Errorf("oauth2/google: no credentials found")
+	}
+	if len(c.RedirectURIs) < 1 {
+		return nil, errors.New("oauth2/google: missing redirect URL in the client_credentials.json")
+	}
+	return &oauth2.Config{
+		ClientID:     c.ClientID,
+		ClientSecret: c.ClientSecret,
+		RedirectURL:  c.RedirectURIs[0],
+		Scopes:       scope,
+		Endpoint: oauth2.Endpoint{
+			AuthURL:  c.AuthURI,
+			TokenURL: c.TokenURI,
+		},
+	}, nil
+}
+
+// JWTConfigFromJSON uses a Google Developers service account JSON key file to read
+// the credentials that authorize and authenticate the requests.
+// Create a service account on "Credentials" page under "APIs & Auth" for your
+// project at https://console.developers.google.com to download a JSON key file.
+func JWTConfigFromJSON(jsonKey []byte, scope ...string) (*jwt.Config, error) {
+	var key struct {
+		Email      string `json:"client_email"`
+		PrivateKey string `json:"private_key"`
+	}
+	if err := json.Unmarshal(jsonKey, &key); err != nil {
+		return nil, err
+	}
+	return &jwt.Config{
+		Email:      key.Email,
+		PrivateKey: []byte(key.PrivateKey),
+		Scopes:     scope,
+		TokenURL:   JWTTokenURL,
+	}, nil
+}
+
+// ComputeTokenSource returns a token source that fetches access tokens
+// from Google Compute Engine (GCE)'s metadata server. It's only valid to use
+// this token source if your program is running on a GCE instance.
+// If no account is specified, "default" is used.
+// Further information about retrieving access tokens from the GCE metadata
+// server can be found at https://cloud.google.com/compute/docs/authentication.
+func ComputeTokenSource(account string) oauth2.TokenSource {
+	return oauth2.ReuseTokenSource(nil, computeSource{account: account})
+}
+
+type computeSource struct {
+	account string
+}
+
+func (cs computeSource) Token() (*oauth2.Token, error) {
+	if !metadata.OnGCE() {
+		return nil, errors.New("oauth2/google: can't get a token from the metadata service; not running on GCE")
+	}
+	acct := cs.account
+	if acct == "" {
+		acct = "default"
+	}
+	tokenJSON, err := metadata.Get("instance/service-accounts/" + acct + "/token")
+	if err != nil {
+		return nil, err
+	}
+	var res struct {
+		AccessToken  string `json:"access_token"`
+		ExpiresInSec int    `json:"expires_in"`
+		TokenType    string `json:"token_type"`
+	}
+	err = json.NewDecoder(strings.NewReader(tokenJSON)).Decode(&res)
+	if err != nil {
+		return nil, fmt.Errorf("oauth2/google: invalid token JSON from metadata: %v", err)
+	}
+	if res.ExpiresInSec == 0 || res.AccessToken == "" {
+		return nil, fmt.Errorf("oauth2/google: incomplete token received from metadata")
+	}
+	return &oauth2.Token{
+		AccessToken: res.AccessToken,
+		TokenType:   res.TokenType,
+		Expiry:      time.Now().Add(time.Duration(res.ExpiresInSec) * time.Second),
+	}, nil
+}