Proxy: Fix updating refresh token in OAuth pass-thru (#26885)

* Handle updating refresh token in oauth pass-thru

Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>

pkg/api/pluginproxy/ds_proxy.go

@@ -307,7 +307,7 @@ func checkWhiteList(c *models.ReqContext, host string) bool {
 func addOAuthPassThruAuth(c *models.ReqContext, req *http.Request) {
 	authInfoQuery := &models.GetAuthInfoQuery{UserId: c.UserId}
 	if err := bus.Dispatch(authInfoQuery); err != nil {
-		logger.Error("Error fetching oauth information for user", "error", err)
+		logger.Error("Error fetching oauth information for user", "userid", c.UserId, "username", c.Login, "error", err)
 		return
 	}
 
@@ -318,20 +318,21 @@ func addOAuthPassThruAuth(c *models.ReqContext, req *http.Request) {
 		return
 	}
 
-	// TokenSource handles refreshing the token if it has expired
-	token, err := connect.TokenSource(c.Req.Context(), &oauth2.Token{
+	persistedToken := &oauth2.Token{
 		AccessToken:  authInfoQuery.Result.OAuthAccessToken,
 		Expiry:       authInfoQuery.Result.OAuthExpiry,
 		RefreshToken: authInfoQuery.Result.OAuthRefreshToken,
 		TokenType:    authInfoQuery.Result.OAuthTokenType,
-	}).Token()
+	}
+	// TokenSource handles refreshing the token if it has expired
+	token, err := connect.TokenSource(c.Req.Context(), persistedToken).Token()
 	if err != nil {
-		logger.Error("Failed to retrieve access token from oauth provider", "provider", authInfoQuery.Result.AuthModule, "error", err)
+		logger.Error("Failed to retrieve access token from OAuth provider", "provider", authInfoQuery.Result.AuthModule, "userid", c.UserId, "username", c.Login, "error", err)
 		return
 	}
 
 	// If the tokens are not the same, update the entry in the DB
-	if token.AccessToken != authInfoQuery.Result.OAuthAccessToken {
+	if !tokensEq(persistedToken, token) {
 		updateAuthCommand := &models.UpdateAuthInfoCommand{
 			UserId:     authInfoQuery.Result.UserId,
 			AuthModule: authInfoQuery.Result.AuthModule,
@@ -339,10 +340,19 @@ func addOAuthPassThruAuth(c *models.ReqContext, req *http.Request) {
 			OAuthToken: token,
 		}
 		if err := bus.Dispatch(updateAuthCommand); err != nil {
-			logger.Error("Failed to update access token during token refresh", "error", err)
+			logger.Error("Failed to update auth info during token refresh", "userid", c.UserId, "username", c.Login, "error", err)
 			return
 		}
+		logger.Debug("Updated OAuth info while proxying an OAuth pass-thru request", "userid", c.UserId, "username", c.Login)
 	}
 	req.Header.Del("Authorization")
 	req.Header.Add("Authorization", fmt.Sprintf("%s %s", token.Type(), token.AccessToken))
 }
+
+// tokensEq checks for OAuth2 token equivalence given the fields of the struct Grafana is interested in
+func tokensEq(t1, t2 *oauth2.Token) bool {
+	return t1.AccessToken == t2.AccessToken &&
+		t1.RefreshToken == t2.RefreshToken &&
+		t1.Expiry == t2.Expiry &&
+		t1.TokenType == t2.TokenType
+}