[Patch] Add Google's FetchUser logic with UserID.

gothic/gothic.go

@@ -366,9 +366,35 @@ func updateSessionValue(session *sessions.Session, key, value string) error {
 	return nil
 }
 
-func FetchUserInfoWithToken(token string) (goth.User, error) {
+func FetchUserInfoWithToken(token string, providerName string, sessionValues interface{}) (goth.User, *goth.Session, error) {
 
 	result := goth.User{}
 
-	return result, nil
+	if token == "" {
+		return result, nil, fmt.Errorf("cannot get user information without accessToken")
+	}
+
+	provider, err := goth.GetProvider(providerName)
+	if err != nil {
+		return result, nil, err
+	}
+
+	session, err := provider.CreateSession(sessionValues)
+	if err != nil {
+		return result, nil, err
+	}
+
+	sess, err := provider.UnmarshalSession(session.Marshal())
+
+	if err != nil {
+		return result, nil, err
+	}
+
+	user, err := provider.FetchUser(sess)
+
+	if err != nil {
+		return result, nil, err
+	}
+
+	return user, &session, nil
 }

providers/google/google.go

@@ -15,7 +15,12 @@ import (
 	"golang.org/x/oauth2"
 )
 
-const endpointProfile string = "https://www.googleapis.com/oauth2/v2/userinfo"
+const (
+	endpointProfile string = "https://www.googleapis.com/oauth2/v2/userinfo"
+	authURL         string = "https://accounts.google.com/o/oauth2/auth?access_type=offline"
+	tokenURL        string = "https://accounts.google.com/o/oauth2/token"
+	idTokenProfile  string = "https://www.googleapis.com/oauth2/v3/tokeninfo"
+)
 
 // New creates a new Google provider, and sets up important connection details.
 // You should always call `google.New` to get a new Provider. Never try to create
@@ -96,16 +101,34 @@ func (p *Provider) FetchUser(session goth.Session) (goth.User, error) {
 		IDToken:      sess.IDToken,
 	}
 
-	if user.AccessToken == "" {
+	if user.AccessToken == "" && user.IDToken == "" {
 		// Data is not yet retrieved, since accessToken is still empty.
-		return user, fmt.Errorf("%s cannot get user information without accessToken", p.providerName)
+		return user, fmt.Errorf("%s cannot get user information without accessToken AND idToken", p.providerName)
+	}
+
+	var response *http.Response
+	var err error
+	// retrievedViaIDToken := false
+
+	if user.IDToken != "" {
+		// retrievedViaIDToken = true
+		response, err = p.Client().Get(idTokenProfile + "?id_token=" + url.QueryEscape(sess.IDToken))
+		if response.StatusCode == http.StatusBadRequest && len(sess.AccessToken) > 0 {
+			response, err = p.Client().Get(endpointProfile + "?access_token=" + url.QueryEscape(sess.AccessToken))
+			// retrievedViaIDToken = false
+		}
+
+	} else {
+		response, err = p.Client().Get(endpointProfile + "?access_token=" + url.QueryEscape(sess.AccessToken))
+	}
+
+	if response != nil {
+		defer response.Body.Close()
 	}
 
-	response, err := p.Client().Get(endpointProfile + "?access_token=" + url.QueryEscape(sess.AccessToken))
 	if err != nil {
 		return user, err
 	}
-	defer response.Body.Close()
 
 	if response.StatusCode != http.StatusOK {
 		return user, fmt.Errorf("%s responded with a %d trying to fetch user information", p.providerName, response.StatusCode)
@@ -212,6 +235,5 @@ func (p *Provider) SetAccessType(at string) {
 }
 
 func (p *Provider) FetchUserWithToken(token string) (goth.User, error) {
-	//TODO: Implement this
 	return goth.User{}, errors.New("not implemented")
 }

providers/google/session.go

@@ -63,5 +63,24 @@ func (p *Provider) UnmarshalSession(data string) (goth.Session, error) {
 }
 
 func (p *Provider) CreateSession(sessionValue interface{}) (goth.Session, error) {
-	return &Session{}, errors.New("not implemented")
+	// First retrieve following keys with it's values from sessionValue
+	// - accessToken
+	// - expiresIn
+	// - clientID
+
+	// Then create a new session with the retrieved values
+	sessStruct := sessionValue.(map[string]interface{})
+
+	accessToken := sessStruct["accessToken"].(string)
+	expiresIn := sessStruct["expiresIn"].(time.Time)
+
+	session := &Session{
+		AccessToken: accessToken,
+		IDToken:     accessToken,
+		ExpiresAt:   expiresIn,
+	}
+
+	// ClientID = clientID
+
+	return session, nil
 }