Call validate on all members

Signed-off-by: Bogdan Drutu <[email protected]>

component/config.go

@@ -15,18 +15,72 @@
 package component // import "go.opentelemetry.io/collector/component"
 
 import (
+	"reflect"
+
+	"go.uber.org/multierr"
+
 	"go.opentelemetry.io/collector/confmap"
 )
 
 // Type is the component type as it is used in the config.
 type Type string
 
+type Config interface {
+	identifiable
+
+	privateConfig()
+}
+
 // ConfigValidator defines an optional interface for configurations to implement to do validation.
 type ConfigValidator interface {
 	// Validate the configuration and returns an error if invalid.
 	Validate() error
 }
 
+// ValidateConfig validates a config, by doing this:
+//   - Call Validate on the config itself if the config implements ConfigValidator.
+//   - Call Validate on every member that implements ConfigValidator. The members can be direct members of the
+//     config structs, part of slices/arrays or part of maps, or member of any other member.
+func ValidateConfig(cfg Config) error {
+	return validate(reflect.ValueOf(cfg))
+}
+
+func validate(t reflect.Value) error {
+	// Validate the value itself.
+	errs := error(nil)
+	// If implements ConfigValidator then call Validate.
+	if validator, ok := t.Interface().(ConfigValidator); ok {
+		errs = validator.Validate()
+	}
+
+	if t.Kind() == reflect.Ptr {
+		t = t.Elem()
+	}
+	switch t.Kind() {
+	case reflect.Struct:
+		// Reflect on the pointed data and check each of its fields.
+		for i := 0; i < t.NumField(); i++ {
+			if !t.Type().Field(i).IsExported() {
+				continue
+			}
+			errs = multierr.Append(errs, validate(t.Field(i)))
+		}
+	case reflect.Slice, reflect.Array:
+		// Reflect on the pointed data and check each of its fields.
+		for i := 0; i < t.Len(); i++ {
+			errs = multierr.Append(errs, validate(t.Index(i)))
+		}
+	case reflect.Map:
+		iter := t.MapRange()
+		for iter.Next() {
+			errs = multierr.Append(errs, validate(iter.Key()))
+			errs = multierr.Append(errs, validate(iter.Value()))
+		}
+	}
+
+	return errs
+}
+
 // DataType is a special Type that represents the data types supported by the collector. We currently support
 // collecting metrics, traces and logs, this can expand in the future.
 type DataType = Type

component/exporter.go

@@ -24,9 +24,7 @@ import (
 // ExporterConfig is the configuration of a component.Exporter. Specific extensions must implement
 // this interface and must embed config.ExporterSettings struct or a struct that extends it.
 type ExporterConfig interface {
-	identifiable
-
-	privateConfigExporter()
+	Config
 }
 
 // UnmarshalExporterConfig helper function to unmarshal an ExporterConfig.

component/extension.go

@@ -23,9 +23,7 @@ import (
 // ExtensionConfig is the configuration of a component.Extension. Specific extensions must implement
 // this interface and must embed config.ExtensionSettings struct or a struct that extends it.
 type ExtensionConfig interface {
-	identifiable
-
-	privateConfigExtension()
+	Config
 }
 
 // UnmarshalExtensionConfig helper function to unmarshal an ExtensionConfig.

component/processor.go

@@ -24,9 +24,7 @@ import (
 // ProcessorConfig is the configuration of a component.Processor. Specific extensions must implement
 // this interface and must embed ProcessorSettings struct or a struct that extends it.
 type ProcessorConfig interface {
-	identifiable
-
-	privateConfigProcessor()
+	Config
 }
 
 // UnmarshalProcessorConfig helper function to unmarshal a ProcessorConfig.

component/receiver.go

@@ -24,9 +24,7 @@ import (
 // ReceiverConfig is the configuration of a component.Receiver. Specific extensions must implement
 // this interface and must embed ReceiverSettings struct or a struct that extends it.
 type ReceiverConfig interface {
-	identifiable
-
-	privateConfigReceiver()
+	Config
 }
 
 // UnmarshalReceiverConfig helper function to unmarshal a ReceiverConfig.

exporter/otlphttpexporter/config_test.go

@@ -37,7 +37,7 @@ func TestUnmarshalDefaultConfig(t *testing.T) {
 	assert.NoError(t, component.UnmarshalExporterConfig(confmap.New(), cfg))
 	assert.Equal(t, factory.CreateDefaultConfig(), cfg)
 	// Default/Empty config is invalid.
-	assert.Error(t, cfg.(component.ConfigValidator).Validate())
+	assert.Error(t, component.ValidateConfig(cfg))
 }
 
 func TestUnmarshalConfig(t *testing.T) {

receiver/otlpreceiver/config_test.go

@@ -193,12 +193,12 @@ func TestUnmarshalConfigEmptyProtocols(t *testing.T) {
 	factory := NewFactory()
 	cfg := factory.CreateDefaultConfig()
 	assert.NoError(t, component.UnmarshalReceiverConfig(cm, cfg))
-	assert.EqualError(t, cfg.(component.ConfigValidator).Validate(), "must specify at least one protocol when using the OTLP receiver")
+	assert.EqualError(t, component.ValidateConfig(cfg), "must specify at least one protocol when using the OTLP receiver")
 }
 
 func TestUnmarshalConfigEmpty(t *testing.T) {
 	factory := NewFactory()
 	cfg := factory.CreateDefaultConfig()
 	assert.NoError(t, component.UnmarshalReceiverConfig(confmap.New(), cfg))
-	assert.EqualError(t, cfg.(component.ConfigValidator).Validate(), "must specify at least one protocol when using the OTLP receiver")
+	assert.EqualError(t, component.ValidateConfig(cfg), "must specify at least one protocol when using the OTLP receiver")
 }

service/config.go

@@ -60,11 +60,7 @@ func (cfg *Config) Validate() error {
 
 	// Validate the receiver configuration.
 	for recvID, recvCfg := range cfg.Receivers {
-		validator, ok := recvCfg.(component.ConfigValidator)
-		if !ok {
-			continue
-		}
-		if err := validator.Validate(); err != nil {
+		if err := component.ValidateConfig(recvCfg); err != nil {
 			return fmt.Errorf("receiver %q has invalid configuration: %w", recvID, err)
 		}
 	}
@@ -77,33 +73,21 @@ func (cfg *Config) Validate() error {
 
 	// Validate the exporter configuration.
 	for expID, expCfg := range cfg.Exporters {
-		validator, ok := expCfg.(component.ConfigValidator)
-		if !ok {
-			continue
-		}
-		if err := validator.Validate(); err != nil {
+		if err := component.ValidateConfig(expCfg); err != nil {
 			return fmt.Errorf("exporter %q has invalid configuration: %w", expID, err)
 		}
 	}
 
 	// Validate the processor configuration.
 	for procID, procCfg := range cfg.Processors {
-		validator, ok := procCfg.(component.ConfigValidator)
-		if !ok {
-			continue
-		}
-		if err := validator.Validate(); err != nil {
+		if err := component.ValidateConfig(procCfg); err != nil {
 			return fmt.Errorf("processor %q has invalid configuration: %w", procID, err)
 		}
 	}
 
 	// Validate the extension configuration.
 	for extID, extCfg := range cfg.Extensions {
-		validator, ok := extCfg.(component.ConfigValidator)
-		if !ok {
-			continue
-		}
-		if err := validator.Validate(); err != nil {
+		if err := component.ValidateConfig(extCfg); err != nil {
 			return fmt.Errorf("extension %q has invalid configuration: %w", extID, err)
 		}
 	}