error.go

package handler

import (
   "context"
   "errors"
   "golang-clean-architecture-ent-gqlgen/pkg/entity/model"

   "github.com/99designs/gqlgen/graphql"
   "github.com/vektah/gqlparser/v2/gqlerror"
)

// HandleError tasks any errors and add it to the graphql errors.
// It is basically intended to be used at the adapter/resolver layer
func HandleError(ctx context.Context, err error) error {
   var extendedError interface{ Extensions() map[string]interface{} }

   for err != nil {
      u, ok := err.(interface {
         Unwrap() error
      })
      if !ok {
         break
      }

      // Skip when its stack strace
      if model.IsStackTrace(err) {
         err = u.Unwrap()
         continue
      }

      // Skip when it's not the standard error type
      if !model.IsError(err) {
         err = u.Unwrap()
         continue
      }

      gqlerr := &gqlerror.Error{
         Path:    graphql.GetPath(ctx),
         Message: err.Error(),
      }
      if errors.As(err, &extendedError) {
         gqlerr.Extensions = extendedError.Extensions()
      }

      graphql.AddError(ctx, gqlerr)

      err = u.Unwrap()
   }

   return nil
}