Add field resolver support to types.yaml

codegen/codegen.go

@@ -58,18 +58,43 @@ func (tm TypeMap) Check() error {
 		if entry.EntityPath == "" {
 			return fmt.Errorf("entity #%d: entityPath is not defined", idx+1)
 		}
+		if err := entry.Fields.Check(); err != nil {
+			return fmt.Errorf("entity #%d: %s", idx+1, err.Error())
+		}
 	}
 	return nil
 }
 
 type TypeMapEntry struct {
-	TypeName   string `yaml:"typeName"`
-	EntityPath string `yaml:"entityPath"`
-	Fields     []TypeMapField
+	TypeName   string       `yaml:"typeName"`
+	EntityPath string       `yaml:"entityPath"`
+	Fields     TypeFieldMap `yaml:"fields"`
+}
+
+type TypeFieldMap []TypeMapField
+
+func (tfm TypeFieldMap) Get(fieldName string) *TypeMapField {
+	for _, field := range tfm {
+		if field.FieldName == fieldName {
+			return &field
+		}
+	}
+
+	return nil
+}
+
+func (tfm TypeFieldMap) Check() error {
+	for idx, field := range tfm {
+		if field.FieldName == "" {
+			return fmt.Errorf("field #%d: fieldName is not defined", idx+1)
+		}
+	}
+	return nil
 }
 
 type TypeMapField struct {
 	FieldName string `yaml:"fieldName"`
+	Resolver  bool   `yaml:"resolver"`
 }
 
 func Generate(cfg Config) error {

codegen/object.go

@@ -22,13 +22,14 @@ type Object struct {
 type Field struct {
 	*Type
 
-	GQLName      string          // The name of the field in graphql
-	GoMethodName string          // The name of the method in go, if any
-	GoVarName    string          // The name of the var in go, if any
-	Args         []FieldArgument // A list of arguments to be passed to this field
-	NoErr        bool            // If this is bound to a go method, does that method have an error as the second argument
-	Object       *Object         // A link back to the parent object
-	Default      interface{}     // The default value
+	GQLName         string          // The name of the field in graphql
+	GoMethodName    string          // The name of the method in go, if any
+	GoVarName       string          // The name of the var in go, if any
+	Args            []FieldArgument // A list of arguments to be passed to this field
+	RequireResolver bool            // Should be emit Resolver method
+	NoErr           bool            // If this is bound to a go method, does that method have an error as the second argument
+	Object          *Object         // A link back to the parent object
+	Default         interface{}     // The default value
 }
 
 type FieldArgument struct {
@@ -60,7 +61,7 @@ func (o *Object) HasResolvers() bool {
 }
 
 func (f *Field) IsResolver() bool {
-	return f.GoMethodName == "" && f.GoVarName == ""
+	return f.RequireResolver || f.GoMethodName == "" && f.GoVarName == ""
 }
 
 func (f *Field) IsConcurrent() bool {

codegen/object_build.go

@@ -81,6 +81,7 @@ func sanitizeGoName(name string) string {
 
 func (cfg *Config) buildObject(types NamedTypes, typ *schema.Object) (*Object, error) {
 	obj := &Object{NamedType: types[typ.TypeName()]}
+	typeEntry := cfg.Typemap.Get(typ.TypeName())
 
 	for _, i := range typ.Interfaces {
 		obj.Satisfies = append(obj.Satisfies, i.Name)
@@ -107,11 +108,19 @@ func (cfg *Config) buildObject(types NamedTypes, typ *schema.Object) (*Object, e
 			args = append(args, newArg)
 		}
 
+		var reqResolver bool
+		if typeEntry != nil {
+			if typeField := typeEntry.Fields.Get(field.Name); typeField != nil {
+				reqResolver = typeField.Resolver
+			}
+		}
+
 		obj.Fields = append(obj.Fields, Field{
-			GQLName: field.Name,
-			Type:    types.getType(field.Type),
-			Args:    args,
-			Object:  obj,
+			GQLName:         field.Name,
+			Type:            types.getType(field.Type),
+			Args:            args,
+			Object:          obj,
+			RequireResolver: reqResolver,
 		})
 	}
 

test/resolvers_test.go

@@ -106,7 +106,7 @@ func (r *testResolvers) Query_jsonEncoding(ctx context.Context) (string, error)
 
 func (r *testResolvers) Query_viewer(ctx context.Context) (*Viewer, error) {
 	return &Viewer{
-		User: &remote_api.User{"Bob"},
+		User: &remote_api.User{Name:"Bob"},
 	}, nil
 }
 
@@ -129,6 +129,10 @@ func (r *testResolvers) Element_error(ctx context.Context, obj *Element) (bool,
 	return false, r.err
 }
 
+func (r *testResolvers) User_likes(ctx context.Context, obj *remote_api.User) ([]string, error) {
+	return obj.Likes, nil
+}
+
 type specialErr struct{}
 
 func (*specialErr) Error() string {

test/schema.graphql

@@ -20,7 +20,9 @@ input DateFilter {
 
 type User {
     name: String
+    likes: [String]
 }
+
 type Viewer {
     user: User
 }

test/types.yaml

@@ -6,3 +6,6 @@
 
 - typeName:   User
   entityPath: remote_api.User
+  fields:
+  - fieldName: likes
+    resolver:  true

test/vendor/remote_api/user.go

@@ -2,4 +2,5 @@ package remote_api
 
 type User struct {
 	Name string
+	Likes []string
 }