feat: add project-owned error catalogs and HTTP 200 failure contracts

response/encoder.go

@@ -3,6 +3,8 @@ package response
 import (
 	"encoding/json"
 	"net/http"
+
+	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
 )
 
 // Result is the transport-independent input to an Encoder. Err is available for
@@ -12,8 +14,13 @@ type Result struct {
 	Code, Message, RequestID string
 	Data                     any
 	Err                      error
+	BusinessCode             any
+	Failed                   bool
 }
 
+// IsError preserves failure semantics independently of the HTTP status.
+func (r Result) IsError() bool { return r.Failed || r.Err != nil || r.Status >= 400 }
+
 // Payload is a complete response. Encoders must be safe for concurrent use.
 // Status and headers are intentionally part of the contract: callback protocols
 // may acknowledge an error using a different HTTP status or media type.
@@ -47,14 +54,30 @@ func Default() Encoder { return defaultEncoder }
 
 // RawJSON leaves successful data unwrapped. Errors use the selected error
 // policy; callback protocols with custom acknowledgments should use EncoderFunc.
+type rawJSONEncoder struct{ errors Encoder }
+
+func (e *rawJSONEncoder) ErrorRegistry() *apierrors.Registry {
+	if p, ok := e.errors.(ErrorRegistryProvider); ok {
+		return p.ErrorRegistry()
+	}
+	return nil
+}
+func (e *rawJSONEncoder) Encode(r Result) (Payload, error) {
+	if r.IsError() {
+		return e.errors.Encode(r)
+	}
+	return JSON(r.Status, r.Data)
+}
 func RawJSON(errors Encoder) Encoder {
 	if errors == nil {
 		errors = Default()
 	}
-	return EncoderFunc(func(r Result) (Payload, error) {
-		if r.Err != nil || r.Status >= 400 {
-			return errors.Encode(r)
-		}
-		return JSON(r.Status, r.Data)
-	})
+	return &rawJSONEncoder{errors: errors}
+}
+
+func (e *rawJSONEncoder) ValidateErrors(catalog apierrors.Catalog) error {
+	if checker, ok := e.errors.(interface{ ValidateErrors(apierrors.Catalog) error }); ok {
+		return checker.ValidateErrors(catalog)
+	}
+	return nil
 }