Omittable input fields (#2585)

README.md

@@ -114,7 +114,7 @@ directive @goModel(model: String, models: [String!]) on OBJECT
     | INTERFACE
     | UNION
 
-directive @goField(forceResolver: Boolean, name: String) on INPUT_FIELD_DEFINITION
+directive @goField(forceResolver: Boolean, name: String, omittable: Boolean) on INPUT_FIELD_DEFINITION
     | FIELD_DEFINITION
 
 type User @goModel(model: "github.com/you/pkg/model.User") {

_examples/config/schema.graphql

@@ -1,5 +1,5 @@
 directive @goModel(model: String, models: [String!]) on OBJECT | INPUT_OBJECT | SCALAR | ENUM | INTERFACE | UNION
-directive @goField(forceResolver: Boolean, name: String) on INPUT_FIELD_DEFINITION | FIELD_DEFINITION
+directive @goField(forceResolver: Boolean, name: String, omittable: Boolean) on INPUT_FIELD_DEFINITION | FIELD_DEFINITION
 
 type Query {
   todos: [Todo!]!

_examples/federation/accounts/gqlgen.yml

@@ -28,6 +28,19 @@ resolver:
 # Optional: turn on to use []Thing instead of []*Thing
 # omit_slice_element_pointers: false
 
+# Optional: turn off to make struct-type struct fields not use pointers
+# e.g. type Thing struct { FieldA OtherThing } instead of { FieldA *OtherThing }
+# struct_fields_always_pointers: true
+
+# Optional: turn off to make resolvers return values instead of pointers for structs
+# resolvers_always_return_pointers: true
+
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
 # Optional: set to speed up generation time by not performing a final validation pass.
 # skip_validation: true
 

_examples/federation/products/gqlgen.yml

@@ -28,6 +28,19 @@ resolver:
 # Optional: turn on to use []Thing instead of []*Thing
 # omit_slice_element_pointers: false
 
+# Optional: turn off to make struct-type struct fields not use pointers
+# e.g. type Thing struct { FieldA OtherThing } instead of { FieldA *OtherThing }
+# struct_fields_always_pointers: true
+
+# Optional: turn off to make resolvers return values instead of pointers for structs
+# resolvers_always_return_pointers: true
+
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
 # Optional: set to speed up generation time by not performing a final validation pass.
 # skip_validation: true
 

_examples/federation/reviews/gqlgen.yml

@@ -28,6 +28,19 @@ resolver:
 # Optional: turn on to use []Thing instead of []*Thing
 # omit_slice_element_pointers: false
 
+# Optional: turn off to make struct-type struct fields not use pointers
+# e.g. type Thing struct { FieldA OtherThing } instead of { FieldA *OtherThing }
+# struct_fields_always_pointers: true
+
+# Optional: turn off to make resolvers return values instead of pointers for structs
+# resolvers_always_return_pointers: true
+
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
 # Optional: set to speed up generation time by not performing a final validation pass.
 # skip_validation: true
 

_examples/websocket-initfunc/server/gqlgen.yml

@@ -23,7 +23,7 @@ resolver:
   dir: graph
   package: graph
 
-# Optional: turn on use ` + "`" + `gqlgen:"fieldName"` + "`" + ` tags in your models
+# Optional: turn on use `gqlgen:"fieldName"` tags in your models
 # struct_tag: json
 
 # Optional: turn on to use []Thing instead of []*Thing
@@ -36,6 +36,12 @@ resolver:
 # Optional: turn off to make resolvers return values instead of pointers for structs
 # resolvers_always_return_pointers: true
 
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
 # Optional: set to speed up generation time by not performing a final validation pass.
 # skip_validation: true
 

api/testdata/default/gqlgen.yml

@@ -29,6 +29,19 @@ resolver:
 # Optional: turn on to use []Thing instead of []*Thing
 # omit_slice_element_pointers: false
 
+# Optional: turn off to make struct-type struct fields not use pointers
+# e.g. type Thing struct { FieldA OtherThing } instead of { FieldA *OtherThing }
+# struct_fields_always_pointers: true
+
+# Optional: turn off to make resolvers return values instead of pointers for structs
+# resolvers_always_return_pointers: true
+
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
 # Optional: set to speed up generation time by not performing a final validation pass.
 # skip_validation: true
 

api/testdata/federation2/gqlgen.yml

@@ -29,6 +29,19 @@ resolver:
 # Optional: turn on to use []Thing instead of []*Thing
 # omit_slice_element_pointers: false
 
+# Optional: turn off to make struct-type struct fields not use pointers
+# e.g. type Thing struct { FieldA OtherThing } instead of { FieldA *OtherThing }
+# struct_fields_always_pointers: true
+
+# Optional: turn off to make resolvers return values instead of pointers for structs
+# resolvers_always_return_pointers: true
+
+# Optional: turn on to return pointers instead of values in unmarshalInput
+# return_pointers_in_unmarshalinput: false
+
+# Optional: wrap nullable input fields with Omittable
+# nullable_input_omittable: true
+
 # Optional: set to speed up generation time by not performing a final validation pass.
 # skip_validation: true
 

codegen/config/binder.go

@@ -20,6 +20,7 @@ type Binder struct {
 	pkgs        *code.Packages
 	schema      *ast.Schema
 	cfg         *Config
+	tctx        *types.Context
 	References  []*TypeReference
 	SawInvalid  bool
 	objectCache map[string]map[string]types.Object
@@ -81,6 +82,14 @@ func (b *Binder) FindType(pkgName string, typeName string) (types.Type, error) {
 	return obj.Type(), nil
 }
 
+func (b *Binder) InstantiateType(orig types.Type, targs []types.Type) (types.Type, error) {
+	if b.tctx == nil {
+		b.tctx = types.NewContext()
+	}
+
+	return types.Instantiate(b.tctx, orig, targs, false)
+}
+
 var (
 	MapType       = types.NewMap(types.Typ[types.String], types.NewInterfaceType(nil, nil).Complete())
 	InterfaceType = types.NewInterfaceType(nil, nil)
@@ -191,6 +200,7 @@ type TypeReference struct {
 	Marshaler               *types.Func // When using external marshalling functions this will point to the Marshal function
 	Unmarshaler             *types.Func // When using external marshalling functions this will point to the Unmarshal function
 	IsMarshaler             bool        // Does the type implement graphql.Marshaler and graphql.Unmarshaler
+	IsOmittable             bool        // Is the type wrapped with Omittable
 	IsContext               bool        // Is the Marshaler/Unmarshaller the context version; applies to either the method or interface variety.
 	PointersInUmarshalInput bool        // Inverse values and pointers in return.
 }
@@ -318,7 +328,35 @@ func isIntf(t types.Type) bool {
 	return ok
 }
 
+func unwrapOmittable(t types.Type) (types.Type, bool) {
+	if t == nil {
+		return t, false
+	}
+	named, ok := t.(*types.Named)
+	if !ok {
+		return t, false
+	}
+	if named.Origin().String() != "github.com/99designs/gqlgen/graphql.Omittable[T any]" {
+		return t, false
+	}
+	return named.TypeArgs().At(0), true
+}
+
 func (b *Binder) TypeReference(schemaType *ast.Type, bindTarget types.Type) (ret *TypeReference, err error) {
+	if innerType, ok := unwrapOmittable(bindTarget); ok {
+		if schemaType.NonNull {
+			return nil, fmt.Errorf("%s is wrapped with Omittable but non-null", schemaType.Name())
+		}
+
+		ref, err := b.TypeReference(schemaType, innerType)
+		if err != nil {
+			return nil, err
+		}
+
+		ref.IsOmittable = true
+		return ref, err
+	}
+
 	if !isValid(bindTarget) {
 		b.SawInvalid = true
 		return nil, fmt.Errorf("%s has an invalid type", schemaType.Name())