config: Do not fail on unknown config keys

Make it a warning.

One such example I found in an old site is `blackfriday`. These should be fixed/removed, but it's not important enough
to fail the build.

diff --git a/config/allconfig/allconfig.go b/config/allconfig/allconfig.go
index 1c1b0b9906e2494ff890a10a846c4f72e7c75250..134df1f5c25c2b3168a023f2f33ec66391b3f03f 100644 (file)
--- a/config/allconfig/allconfig.go
+++ b/config/allconfig/allconfig.go
@@ -744,7 +744,7 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
 
        all := &Config{}
 
-       err := decodeConfigFromParams(fs, bcfg, cfg, all, nil)
+       err := decodeConfigFromParams(fs, logger, bcfg, cfg, all, nil)
        if err != nil {
                return nil, err
        }
@@ -832,7 +832,7 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
                        // Create a copy of the complete config and replace the root keys with the language specific ones.
                        clone := all.cloneForLang()
 
-                       if err := decodeConfigFromParams(fs, bcfg, mergedConfig, clone, differentRootKeys); err != nil {
+                       if err := decodeConfigFromParams(fs, logger, bcfg, mergedConfig, clone, differentRootKeys); err != nil {
                                return nil, fmt.Errorf("failed to decode config for language %q: %w", k, err)
                        }
                        if err := clone.CompileConfig(logger); err != nil {
@@ -904,7 +904,7 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
        return cm, nil
 }
 
-func decodeConfigFromParams(fs afero.Fs, bcfg config.BaseConfig, p config.Provider, target *Config, keys []string) error {
+func decodeConfigFromParams(fs afero.Fs, logger loggers.Logger, bcfg config.BaseConfig, p config.Provider, target *Config, keys []string) error {
 
        var decoderSetups []decodeWeight
 
@@ -917,7 +917,7 @@ func decodeConfigFromParams(fs afero.Fs, bcfg config.BaseConfig, p config.Provid
                        if v, found := allDecoderSetups[key]; found {
                                decoderSetups = append(decoderSetups, v)
                        } else {
-                               return fmt.Errorf("unknown config key %q", key)
+                               logger.Warnf("Skip unknown config key %q", key)
                        }
                }
        }