resources/images: Stabilize order of valid sources in error message

Closes #14390

diff --git a/resources/images/config.go b/resources/images/config.go
index c24651da5e01d71c7a6ab00bb74ef7bfa7681064..3277d2a24698153b6861fb70f187da916fc425bb 100644 (file)
--- a/resources/images/config.go
+++ b/resources/images/config.go
@@ -496,7 +496,9 @@ func (cfg *ImagingConfig) init() error {
                for i, s := range cfg.Meta.Sources {
                        cfg.Meta.Sources[i] = strings.ToLower(s)
                        if !validMetaSources[cfg.Meta.Sources[i]] {
-                               return fmt.Errorf("invalid metadata source %q in imaging.meta.sources config; must be one of %s", s, slices.Collect(maps.Keys(validMetaSources)))
+                               keys := slices.Collect(maps.Keys(validMetaSources))
+                               slices.Sort(keys)
+                               return fmt.Errorf("invalid metadata source %q in imaging.meta.sources config; must be one of %s", s, keys)
                        }
                }
        }