From f06f962d84c40718528e4e908d73c13e7d8fe774 Mon Sep 17 00:00:00 2001
From: Jannis Mattheis <contact@jmattheis.de>
Date: Wed, 15 Jul 2026 19:59:18 +0200
Subject: [PATCH] fix: error when legacy config exists

---
 config/config_test.go | 12 ++++++++++++
 config/file.go        | 13 +++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/config/config_test.go b/config/config_test.go
index 216d80789..39d536479 100644
--- a/config/config_test.go
+++ b/config/config_test.go
@@ -74,6 +74,18 @@ func TestGotifyConfigFile(t *testing.T) {
 	assert.Equal(t, "fromfile", conf.DefaultUser.Name)
 }
 
+func TestLegacyConfigFile(t *testing.T) {
+	mode.Set(mode.TestDev)
+	dir := t.TempDir()
+	assert.NoError(t, os.WriteFile(filepath.Join(dir, "config.yml"), []byte(""), 0o600))
+	t.Chdir(dir)
+
+	_, logs := Get()
+
+	assert.Len(t, logs, 1)
+	assert.Contains(t, logs[0].Msg, "the YAML config file is no longer supported. Convert it with 'gotify-server migrate-config")
+}
+
 func TestAddSlash(t *testing.T) {
 	mode.Set(mode.TestDev)
 	os.Setenv("GOTIFY_UPLOADEDIMAGESDIR", "../data/images")
diff --git a/config/file.go b/config/file.go
index 9479cfd0f..5380f7283 100644
--- a/config/file.go
+++ b/config/file.go
@@ -11,7 +11,20 @@ import (
 
 var osStat = os.Stat
 
+func checkLegacyConfigFiles() error {
+	for _, file := range []string{"config.yml", "/etc/gotify/config.yml"} {
+		if _, err := osStat(file); err == nil {
+			return fmt.Errorf("found %s, the YAML config file is no longer supported. Convert it with 'gotify-server migrate-config %s', see https://gotify.net/docs/migrate-to-3", file, file)
+		}
+	}
+	return nil
+}
+
 func loadFiles() []FutureLog {
+	if err := checkLegacyConfigFiles(); err != nil {
+		return []FutureLog{futureFatal(err.Error())}
+	}
+
 	if configFile := os.Getenv("GOTIFY_CONFIG_FILE"); configFile != "" {
 		log, _ := loadFile(configFile)
 		return []FutureLog{log}