Add GoogleIdProvider.

idp/github.go

@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"io/ioutil"
 	"net/http"
+	"sync"
 
 	"golang.org/x/oauth2"
 )
@@ -25,20 +26,20 @@ import (
 type GithubIdProvider struct{}
 
 func (idp *GithubIdProvider) GetConfig() *oauth2.Config {
-	var githubEndpoint = oauth2.Endpoint{
+	var endpoint = oauth2.Endpoint{
 		AuthURL:  "https://github.com/login/oauth/authorize",
 		TokenURL: "https://github.com/login/oauth/access_token",
 	}
 
-	var githubOauthConfig = &oauth2.Config{
+	var config = &oauth2.Config{
 		Scopes:   []string{"user:email", "read:user"},
-		Endpoint: githubEndpoint,
+		Endpoint: endpoint,
 	}
 
-	return githubOauthConfig
+	return config
 }
 
-func (idp *GithubIdProvider) GetEmail(httpClient *http.Client, token *oauth2.Token) string {
+func (idp *GithubIdProvider) getEmail(httpClient *http.Client, token *oauth2.Token) string {
 	res := ""
 
 	type GithubEmail struct {
@@ -74,7 +75,7 @@ func (idp *GithubIdProvider) GetEmail(httpClient *http.Client, token *oauth2.Tok
 	return res
 }
 
-func (idp *GithubIdProvider) GetLoginAndAvatar(httpClient *http.Client, token *oauth2.Token) (string, string) {
+func (idp *GithubIdProvider) getLoginAndAvatar(httpClient *http.Client, token *oauth2.Token) (string, string) {
 	type GithubUser struct {
 		Login     string `json:"login"`
 		AvatarUrl string `json:"avatar_url"`
@@ -86,12 +87,12 @@ func (idp *GithubIdProvider) GetLoginAndAvatar(httpClient *http.Client, token *o
 		panic(err)
 	}
 	req.Header.Add("Authorization", "token "+token.AccessToken)
-	response2, err := httpClient.Do(req)
+	resp, err := httpClient.Do(req)
 	if err != nil {
 		panic(err)
 	}
-	defer response2.Body.Close()
-	contents2, err := ioutil.ReadAll(response2.Body)
+	defer resp.Body.Close()
+	contents2, err := ioutil.ReadAll(resp.Body)
 	err = json.Unmarshal(contents2, &githubUser)
 	if err != nil {
 		panic(err)
@@ -99,3 +100,21 @@ func (idp *GithubIdProvider) GetLoginAndAvatar(httpClient *http.Client, token *o
 
 	return githubUser.Login, githubUser.AvatarUrl
 }
+
+func (idp *GithubIdProvider) GetUserInfo(httpClient *http.Client, token *oauth2.Token) (string, string, string, error) {
+	var email, username, avatarUrl string
+
+	var wg sync.WaitGroup
+	wg.Add(2)
+	go func() {
+		email = idp.getEmail(httpClient, token)
+		wg.Done()
+	}()
+	go func() {
+		username, avatarUrl = idp.getLoginAndAvatar(httpClient, token)
+		wg.Done()
+	}()
+	wg.Wait()
+
+	return email, username, avatarUrl, nil
+}

idp/google.go

@@ -0,0 +1,66 @@
+// Copyright 2021 The casbin Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package idp
+
+import (
+	"encoding/json"
+	"errors"
+	"io/ioutil"
+	"net/http"
+
+	"golang.org/x/oauth2"
+)
+
+type GoogleIdProvider struct{}
+
+func (idp *GoogleIdProvider) GetConfig() *oauth2.Config {
+	var endpoint = oauth2.Endpoint{
+		AuthURL:  "https://accounts.google.com/o/oauth2/auth",
+		TokenURL: "https://accounts.google.com/o/oauth2/token",
+	}
+
+	var config = &oauth2.Config{
+		Scopes:   []string{"profile", "email"},
+		Endpoint: endpoint,
+	}
+
+	return config
+}
+
+func (idp *GoogleIdProvider) GetUserInfo(httpClient *http.Client, token *oauth2.Token) (string, string, string, error) {
+	var email, username, avatarUrl string
+
+	type userInfoFromGoogle struct {
+		Picture string `json:"picture"`
+		Email   string `json:"email"`
+	}
+
+	resp, err := httpClient.Get("https://www.googleapis.com/oauth2/v2/userinfo?alt=json&access_token=" + token.AccessToken)
+	defer resp.Body.Close()
+	contents, err := ioutil.ReadAll(resp.Body)
+	var tempUser userInfoFromGoogle
+	err = json.Unmarshal(contents, &tempUser)
+	if err != nil {
+		panic(err)
+	}
+	email = tempUser.Email
+	avatarUrl = tempUser.Picture
+
+	if email == "" {
+		return email, username, avatarUrl, errors.New("google email is empty, please try again")
+	}
+
+	return email, username, avatarUrl, nil
+}

idp/provider.go

@@ -22,13 +22,14 @@ import (
 
 type IdProvider interface {
 	GetConfig() *oauth2.Config
-	GetEmail(httpClient *http.Client, token *oauth2.Token) string
-	GetLoginAndAvatar(httpClient *http.Client, token *oauth2.Token) (string, string)
+	GetUserInfo(httpClient *http.Client, token *oauth2.Token) (string, string, string, error)
 }
 
 func GetIdProvider(providerType string) IdProvider {
 	if providerType == "github" {
 		return &GithubIdProvider{}
+	} else if providerType == "google" {
+		return &GoogleIdProvider{}
 	}
 
 	return nil