예제 #1
0
func completeValueCatchingError(eCtx *ExecutionContext, returnType Type, fieldASTs []*ast.Field, info ResolveInfo, result interface{}) (completed interface{}) {
	// catch panic
	defer func() interface{} {
		if r := recover(); r != nil {
			//send panic upstream
			if _, ok := returnType.(*NonNull); ok {
				panic(r)
			}
			if err, ok := r.(gqlerrors.FormattedError); ok {
				eCtx.Errors = append(eCtx.Errors, err)
			}
			return completed
		}
		return completed
	}()

	if returnType, ok := returnType.(*NonNull); ok {
		completed := completeValue(eCtx, returnType, fieldASTs, info, result)
		return completed
	}
	completed = completeValue(eCtx, returnType, fieldASTs, info, result)
	resultVal := reflect.ValueOf(completed)
	if resultVal.IsValid() && resultVal.Type().Kind() == reflect.Func {
		if propertyFn, ok := completed.(func() interface{}); ok {
			return propertyFn()
		}
		err := gqlerrors.NewFormattedError("Error resolving func. Expected `func() interface{}` signature")
		panic(gqlerrors.FormatError(err))
	}
	return completed
}
예제 #2
0
func invariant(condition bool, message string) error {
	if !condition {
		return gqlerrors.NewFormattedError(message)
	}
	return nil
}
예제 #3
0
func completeValue(eCtx *ExecutionContext, returnType Type, fieldASTs []*ast.Field, info ResolveInfo, result interface{}) interface{} {

	// TODO: explore resolving go-routines in completeValue

	resultVal := reflect.ValueOf(result)
	if resultVal.IsValid() && resultVal.Type().Kind() == reflect.Func {
		if propertyFn, ok := result.(func() interface{}); ok {
			return propertyFn()
		}
		err := gqlerrors.NewFormattedError("Error resolving func. Expected `func() interface{}` signature")
		panic(gqlerrors.FormatError(err))
	}

	if returnType, ok := returnType.(*NonNull); ok {
		completed := completeValue(eCtx, returnType.OfType, fieldASTs, info, result)
		if completed == nil {
			err := NewLocatedError(
				fmt.Sprintf("Cannot return null for non-nullable field %v.%v.", info.ParentType, info.FieldName),
				FieldASTsToNodeASTs(fieldASTs),
			)
			panic(gqlerrors.FormatError(err))
		}
		return completed
	}

	if isNullish(result) {
		return nil
	}

	// If field type is List, complete each item in the list with the inner type
	if returnType, ok := returnType.(*List); ok {

		resultVal := reflect.ValueOf(result)
		err := invariant(
			resultVal.IsValid() && resultVal.Type().Kind() == reflect.Slice,
			"User Error: expected iterable, but did not find one.",
		)
		if err != nil {
			panic(gqlerrors.FormatError(err))
		}

		itemType := returnType.OfType
		completedResults := []interface{}{}
		for i := 0; i < resultVal.Len(); i++ {
			val := resultVal.Index(i).Interface()
			completedItem := completeValueCatchingError(eCtx, itemType, fieldASTs, info, val)
			completedResults = append(completedResults, completedItem)
		}
		return completedResults
	}

	// If field type is Scalar or Enum, serialize to a valid value, returning
	// null if serialization is not possible.
	if returnType, ok := returnType.(*Scalar); ok {
		serializedResult := returnType.Serialize(result)
		if isNullish(serializedResult) {
			return nil
		}
		return serializedResult
	}
	if returnType, ok := returnType.(*Enum); ok {
		serializedResult := returnType.Serialize(result)
		if isNullish(serializedResult) {
			return nil
		}
		return serializedResult
	}

	// ast.Field type must be Object, Interface or Union and expect sub-selections.
	var objectType *Object
	switch returnType := returnType.(type) {
	case *Object:
		objectType = returnType
	case Abstract:
		objectType = returnType.ObjectType(result, info)
		if objectType != nil && !returnType.IsPossibleType(objectType) {
			panic(gqlerrors.NewFormattedError(
				fmt.Sprintf(`Runtime Object type "%v" is not a possible type `+
					`for "%v".`, objectType, returnType),
			))
		}
	}
	if objectType == nil {
		return nil
	}

	// If there is an isTypeOf predicate function, call it with the
	// current result. If isTypeOf returns false, then raise an error rather
	// than continuing execution.
	if objectType.IsTypeOf != nil && !objectType.IsTypeOf(result, info) {
		panic(gqlerrors.NewFormattedError(
			fmt.Sprintf(`Expected value of type "%v" but got: %T.`, objectType, result),
		))
	}

	// Collect sub-fields to execute to complete this value.
	subFieldASTs := map[string][]*ast.Field{}
	visitedFragmentNames := map[string]bool{}
	for _, fieldAST := range fieldASTs {
		if fieldAST == nil {
			continue
		}
		selectionSet := fieldAST.SelectionSet
		if selectionSet != nil {
			innerParams := CollectFieldsParams{
				ExeContext:           eCtx,
				OperationType:        objectType,
				SelectionSet:         selectionSet,
				Fields:               subFieldASTs,
				VisitedFragmentNames: visitedFragmentNames,
			}
			subFieldASTs = collectFields(innerParams)
		}
	}
	executeFieldsParams := ExecuteFieldsParams{
		ExecutionContext: eCtx,
		ParentType:       objectType,
		Source:           result,
		Fields:           subFieldASTs,
	}
	results := executeFields(executeFieldsParams)

	return results.Data

}