feat: convert grpc errors to http status codes (#1997)

* feat: convert grpc errors to http status codes

* chore: circuit break include unimplemented grpc error

* chore: add reference link in comments

rest/httpx/responses.go

@@ -6,6 +6,7 @@ import (
 	"sync"
 
 	"github.com/zeromicro/go-zero/core/logx"
+	"github.com/zeromicro/go-zero/rest/internal/errcode"
 	"github.com/zeromicro/go-zero/rest/internal/header"
 )
 
@@ -23,9 +24,14 @@ func Error(w http.ResponseWriter, err error, fns ...func(w http.ResponseWriter,
 	if handler == nil {
 		if len(fns) > 0 {
 			fns[0](w, err)
+		} else if errcode.IsGrpcError(err) {
+			// don't unwrap error and get status.Message(),
+			// it hides the rpc error headers.
+			http.Error(w, err.Error(), errcode.CodeFromGrpcError(err))
 		} else {
 			http.Error(w, err.Error(), http.StatusBadRequest)
 		}
+
 		return
 	}