#514 - Fix login with Gitea OAuth problems: external user ID not properly recorded.

oauth.go

@@ -293,10 +293,15 @@ func configureGiteaOauth(parentHandler *Handler, r *mux.Router, app *App) {
 			ClientID:         app.Config().GiteaOauth.ClientID,
 			ClientSecret:     app.Config().GiteaOauth.ClientSecret,
 			ExchangeLocation: app.Config().GiteaOauth.Host + "/login/oauth/access_token",
-			InspectLocation:  app.Config().GiteaOauth.Host + "/api/v1/user",
+			InspectLocation:  app.Config().GiteaOauth.Host + "/login/oauth/userinfo",
 			AuthLocation:     app.Config().GiteaOauth.Host + "/login/oauth/authorize",
 			HttpClient:       config.DefaultHTTPClient(),
 			CallbackLocation: callbackLocation,
+			Scope:            "openid profile email",
+			MapUserID:        "sub",
+			MapUsername:      "login",
+			MapDisplayName:   "full_name",
+			MapEmail:         "email",
 		}
 		configureOauthRoutes(parentHandler, r, app, oauthClient, callbackProxy)
 	}
@@ -355,7 +360,7 @@ func (h oauthHandler) viewOauthCallback(app *App, w http.ResponseWriter, r *http
 	}
 
 	if localUserID != -1 && attachUserID > 0 {
-		if err = addSessionFlash(app, w, r, "This Slack account is already attached to another user.", nil); err != nil {
+		if err = addSessionFlash(app, w, r, "This OAuth account is already attached to another user.", nil); err != nil {
 			return impart.HTTPError{Status: http.StatusInternalServerError, Message: err.Error()}
 		}
 		return impart.HTTPError{http.StatusFound, "/me/settings"}
@@ -376,6 +381,7 @@ func (h oauthHandler) viewOauthCallback(app *App, w http.ResponseWriter, r *http
 	}
 	if attachUserID > 0 {
 		log.Info("attaching to user %d", attachUserID)
+		log.Info("OAuth userid: %s", tokenInfo.UserID)
 		err = h.DB.RecordRemoteUserID(r.Context(), attachUserID, tokenInfo.UserID, provider, clientID, tokenResponse.AccessToken)
 		if err != nil {
 			return impart.HTTPError{http.StatusInternalServerError, err.Error()}

oauth_gitea.go

@@ -3,6 +3,8 @@ package writefreely
 import (
 	"context"
 	"errors"
+	"fmt"
+	"github.com/writeas/web-core/log"
 	"net/http"
 	"net/url"
 	"strings"
@@ -15,6 +17,11 @@ type giteaOauthClient struct {
 	ExchangeLocation string
 	InspectLocation  string
 	CallbackLocation string
+	Scope            string
+	MapUserID        string
+	MapUsername      string
+	MapDisplayName   string
+	MapEmail         string
 	HttpClient       HttpClient
 }
 
@@ -46,7 +53,7 @@ func (c giteaOauthClient) buildLoginURL(state string) (string, error) {
 	q.Set("redirect_uri", c.CallbackLocation)
 	q.Set("response_type", "code")
 	q.Set("state", state)
-	// q.Set("scope", "read_user")
+	q.Set("scope", c.Scope)
 	u.RawQuery = q.Encode()
 	return u.String(), nil
 }
@@ -55,7 +62,7 @@ func (c giteaOauthClient) exchangeOauthCode(ctx context.Context, code string) (*
 	form := url.Values{}
 	form.Add("grant_type", "authorization_code")
 	form.Add("redirect_uri", c.CallbackLocation)
-	// form.Add("scope", "read_user")
+	form.Add("scope", c.Scope)
 	form.Add("code", code)
 	req, err := http.NewRequest("POST", c.ExchangeLocation, strings.NewReader(form.Encode()))
 	if err != nil {
@@ -103,12 +110,24 @@ func (c giteaOauthClient) inspectOauthAccessToken(ctx context.Context, accessTok
 		return nil, errors.New("unable to inspect access token")
 	}
 
-	var inspectResponse InspectResponse
-	if err := limitedJsonUnmarshal(resp.Body, infoRequestMaxLen, &inspectResponse); err != nil {
+	// since we don't know what the JSON from the server will look like, we create a
+	// generic interface and then map manually to values set in the config
+	var genericInterface map[string]interface{}
+	if err := limitedJsonUnmarshal(resp.Body, infoRequestMaxLen, &genericInterface); err != nil {
 		return nil, err
 	}
-	if inspectResponse.Error != "" {
-		return nil, errors.New(inspectResponse.Error)
+
+	// map each relevant field in inspectResponse to the mapped field from the config
+	var inspectResponse InspectResponse
+	inspectResponse.UserID, _ = genericInterface[c.MapUserID].(string)
+	// log.Info("Userid from Gitea: %s", inspectResponse.UserID)
+	if inspectResponse.UserID == "" {
+		log.Error("[CONFIGURATION ERROR] Gitea OAuth provider returned empty UserID value (`%s`).\n  Do you need to configure a different `map_user_id` value for this provider?", c.MapUserID)
+		return nil, fmt.Errorf("no UserID (`%s`) value returned", c.MapUserID)
 	}
+	inspectResponse.Username, _ = genericInterface[c.MapUsername].(string)
+	inspectResponse.DisplayName, _ = genericInterface[c.MapDisplayName].(string)
+	inspectResponse.Email, _ = genericInterface[c.MapEmail].(string)
+
 	return &inspectResponse, nil
 }