Esempio n. 1
0
func Execute(p ExecuteParams, resultChan chan *Result) {
	var errors []gqlerrors.FormattedError
	var result Result
	params := BuildExecutionCtxParams{
		Schema:        p.Schema,
		Root:          p.Root,
		AST:           p.AST,
		OperationName: p.OperationName,
		Args:          p.Args,
		Errors:        errors,
		Result:        &result,
		ResultChan:    resultChan,
	}
	exeContext := buildExecutionContext(params)
	if result.HasErrors() {
		return
	}
	defer func() {
		if r := recover(); r != nil {
			var err error
			if r, ok := r.(error); ok {
				err = gqlerrors.FormatError(r)
			}
			exeContext.Errors = append(exeContext.Errors, gqlerrors.FormatError(err))
			result.Errors = exeContext.Errors
			resultChan <- &result
		}
	}()
	eOperationParams := ExecuteOperationParams{
		ExecutionContext: exeContext,
		Root:             p.Root,
		Operation:        exeContext.Operation,
	}
	executeOperation(eOperationParams, resultChan)
}
Esempio n. 2
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
}
Esempio n. 3
0
func buildExecutionContext(p BuildExecutionCtxParams) *ExecutionContext {
	eCtx := &ExecutionContext{}
	operations := map[string]ast.Definition{}
	fragments := map[string]ast.Definition{}
	for _, statement := range p.AST.Definitions {
		switch stm := statement.(type) {
		case *ast.OperationDefinition:
			key := ""
			if stm.GetName() != nil && stm.GetName().Value != "" {
				key = stm.GetName().Value
			}
			operations[key] = stm
		case *ast.FragmentDefinition:
			key := ""
			if stm.GetName() != nil && stm.GetName().Value != "" {
				key = stm.GetName().Value
			}
			fragments[key] = stm
		default:
			err := gqlerrors.NewFormattedError(
				fmt.Sprintf("GraphQL cannot execute a request containing a %v", statement.GetKind()),
			)
			p.Result.Errors = append(p.Result.Errors, err)
			p.ResultChan <- p.Result
			return eCtx
		}
	}
	if (p.OperationName == "") && (len(operations) != 1) {
		err := gqlerrors.NewFormattedError("Must provide operation name if query contains multiple operations.")
		p.Result.Errors = append(p.Result.Errors, err)
		p.ResultChan <- p.Result
		return eCtx
	}
	opName := p.OperationName
	if opName == "" {
		// get first opName
		for k, _ := range operations {
			opName = k
			break
		}
	}
	operation, found := operations[opName]
	if !found {
		err := gqlerrors.NewFormattedError(fmt.Sprintf(`Unknown operation named "%v".`, opName))
		p.Result.Errors = append(p.Result.Errors, err)
		p.ResultChan <- p.Result
		return eCtx
	}
	variableValues, err := getVariableValues(p.Schema, operation.GetVariableDefinitions(), p.Args)
	if err != nil {
		p.Result.Errors = append(p.Result.Errors, gqlerrors.FormatError(err))
		p.ResultChan <- p.Result
		return eCtx
	}

	eCtx.Schema = p.Schema
	eCtx.Fragments = fragments
	eCtx.Root = p.Root
	eCtx.Operation = operation
	eCtx.VariableValues = variableValues
	eCtx.Errors = p.Errors
	return eCtx
}
Esempio n. 4
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 {
		err := invariant(returnType.Serialize != nil, "Missing serialize method on type")
		if err != nil {
			panic(gqlerrors.FormatError(err))
		}
		serializedResult := returnType.Serialize(result)
		if isNullish(serializedResult) {
			return nil
		}
		return serializedResult
	}
	if returnType, ok := returnType.(*Enum); ok {
		err := invariant(returnType.Serialize != nil, "Missing serialize method on type")
		if err != nil {
			panic(gqlerrors.FormatError(err))
		}
		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.GetObjectType(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

}
Esempio n. 5
0
/**
 * Resolves the field on the given source object. In particular, this
 * figures out the value that the field returns by calling its resolve function,
 * then calls completeValue to complete promises, serialize scalars, or execute
 * the sub-selection-set for objects.
 */
func resolveField(eCtx *ExecutionContext, parentType *Object, source interface{}, fieldASTs []*ast.Field) (result interface{}, resultState resolveFieldResultState) {
	// catch panic from resolveFn
	var returnType Output
	defer func() (interface{}, resolveFieldResultState) {
		if r := recover(); r != nil {

			var err error
			if r, ok := r.(string); ok {
				err = NewLocatedError(
					fmt.Sprintf("%v", r),
					FieldASTsToNodeASTs(fieldASTs),
				)
			}
			if r, ok := r.(error); ok {
				err = gqlerrors.FormatError(r)
			}
			// send panic upstream
			if _, ok := returnType.(*NonNull); ok {
				panic(gqlerrors.FormatError(err))
			}
			eCtx.Errors = append(eCtx.Errors, gqlerrors.FormatError(err))
			return result, resultState
		}
		return result, resultState
	}()

	fieldAST := fieldASTs[0]
	fieldName := ""
	if fieldAST.Name != nil {
		fieldName = fieldAST.Name.Value
	}

	fieldDef := getFieldDef(eCtx.Schema, parentType, fieldName)
	if fieldDef == nil {
		resultState.hasNoFieldDefs = true
		return nil, resultState
	}
	returnType = fieldDef.Type
	resolveFn := fieldDef.Resolve
	if resolveFn == nil {
		resolveFn = defaultResolveFn
	}

	// Build a map of arguments from the field.arguments AST, using the
	// variables scope to fulfill any variable references.
	// TODO: find a way to memoize, in case this field is within a List type.
	args, _ := getArgumentValues(fieldDef.Args, fieldAST.Arguments, eCtx.VariableValues)

	// The resolve function's optional third argument is a collection of
	// information about the current execution state.
	info := ResolveInfo{
		FieldName:      fieldName,
		FieldASTs:      fieldASTs,
		ReturnType:     returnType,
		ParentType:     parentType,
		Schema:         eCtx.Schema,
		Fragments:      eCtx.Fragments,
		RootValue:      eCtx.Root,
		Operation:      eCtx.Operation,
		VariableValues: eCtx.VariableValues,
	}

	// TODO: If an error occurs while calling the field `resolve` function, ensure that
	// it is wrapped as a Error with locations. Log this error and return
	// null if allowed, otherwise throw the error so the parent field can handle
	// it.
	result = resolveFn(GQLFRParams{
		Source: source,
		Args:   args,
		Info:   info,
	})

	completed := completeValueCatchingError(eCtx, returnType, fieldASTs, info, result)
	return completed, resultState
}