Add method support

codegen/input_build.go

@@ -52,6 +52,7 @@ func (cfg *Config) buildInput(types NamedTypes, typ *ast.Definition) (*Object, e
 		var goVarName string
 		if entryExists {
 			if typeField, ok := typeEntry.Fields[field.Name]; ok {
+				// It may be a method but treat it as a variable now
 				goVarName = typeField.ModelName
 			}
 		}

codegen/object_build.go

@@ -133,6 +133,7 @@ func (cfg *Config) buildObject(types NamedTypes, typ *ast.Definition, imports *I
 		var goVarName string
 		if entryExists {
 			if typeField, ok := typeEntry.Fields[field.Name]; ok {
+				// It may be a method but treat it as a variable now
 				goVarName = typeField.ModelName
 				forceResolver = typeField.Resolver
 			}

codegen/templates/field.gotpl

@@ -49,14 +49,14 @@
 			resTmp := ec.FieldMiddleware(ctx, func(ctx context.Context) (interface{}, error) {
 				{{- if $field.IsResolver }}
 					return ec.resolvers.{{ $field.ShortInvocation }}
-				{{- else if $field.GoVarName }}
-					return obj.{{$field.GoVarName}}, nil
 				{{- else if $field.GoMethodName }}
 					{{- if $field.NoErr }}
 						return {{$field.GoMethodName}}({{ $field.CallArgs }}), nil
 					{{- else }}
 						return {{$field.GoMethodName}}({{ $field.CallArgs }})
 					{{- end }}
+				{{- else if $field.GoVarName }}
+					return obj.{{$field.GoVarName}}, nil
 				{{- end }}
 			})
 			if resTmp == nil {

codegen/util.go

@@ -194,10 +194,15 @@ func bindMethod(imports *Imports, t types.Type, field *Field) error {
 		return fmt.Errorf("not a named type")
 	}
 
-	method := findMethod(namedType, field.GQLName)
+	goName := field.GQLName
+	if field.GoVarName != "" {
+		goName = field.GoVarName
+	}
+	method := findMethod(namedType, goName)
 	if method == nil {
 		return fmt.Errorf("no method named %s", field.GQLName)
 	}
+	field.GoVarName = "" // found it to be a method, not a variable
 	sig := method.Type().(*types.Signature)
 
 	if sig.Results().Len() == 1 {
@@ -227,7 +232,11 @@ func bindVar(imports *Imports, t types.Type, field *Field) error {
 		return fmt.Errorf("not a struct")
 	}
 
-	structField := findField(underlying, field.GQLName)
+	goName := field.GQLName
+	if field.GoVarName != "" {
+		goName = field.GoVarName
+	}
+	structField := findField(underlying, goName)
 	if structField == nil {
 		return fmt.Errorf("no field named %s", field.GQLName)
 	}

example/config/.gqlgen.yml

@@ -16,13 +16,13 @@ models:
   Todo:    # Object
     fields:
       text:
-        modelField: Description
+        modelField: Description # Field
   NewTodo: # Input
     fields:
       userId:
-        modelField: UserID
+        modelField: UserID      # Field
   User:
     model: github.com/vektah/gqlgen/example/config.User
     fields:
       name:
-        modelField: FullName
+        modelField: FullName    # Method

example/config/model.go

@@ -1,6 +1,12 @@
 package config
 
+import "fmt"
+
 type User struct {
-	ID   string
-	FullName string
+	ID                  string
+	FirstName, LastName string
+}
+
+func (user *User) FullName() string {
+	return fmt.Sprintf("%s %s", user.FirstName, user.LastName)
 }

example/config/schema.graphql

@@ -25,4 +25,4 @@ input NewTodo {
 
 type Mutation {
   createTodo(input: NewTodo!): Todo!
-}
+}