Allow custom resolver filenames using filename_template option

codegen/config/resolver.go

@@ -10,11 +10,12 @@ import (
 )
 
 type ResolverConfig struct {
-	Filename string         `yaml:"filename,omitempty"`
-	Package  string         `yaml:"package,omitempty"`
-	Type     string         `yaml:"type,omitempty"`
-	Layout   ResolverLayout `yaml:"layout,omitempty"`
-	DirName  string         `yaml:"dir"`
+	Filename         string         `yaml:"filename,omitempty"`
+	FilenameTemplate string         `yaml:"filename_template,omitempty"`
+	Package          string         `yaml:"package,omitempty"`
+	Type             string         `yaml:"type,omitempty"`
+	Layout           ResolverLayout `yaml:"layout,omitempty"`
+	DirName          string         `yaml:"dir"`
 }
 
 type ResolverLayout string

docs/content/config.md

@@ -35,6 +35,7 @@ resolver:
   layout: follow-schema
   dir: graph
   package: graph
+  filename_template: "{name}.custom.go"
 
 # Optional: turn on use ` + "`" + `gqlgen:"fieldName"` + "`" + ` tags in your models
 # struct_tag: json

plugin/resolvergen/resolver.go

@@ -88,7 +88,7 @@ func (m *Plugin) generatePerSchema(data *codegen.Data) error {
 
 	for _, o := range data.Objects {
 		if o.HasResolvers() {
-			fn := gqlToResolverName(data.Config.Resolver.Dir(), o.Position.Src.Name)
+			fn := gqlToResolverName(data.Config.Resolver.Dir(), o.Position.Src.Name, data.Config.Resolver.FilenameTemplate)
 			if files[fn] == nil {
 				files[fn] = &File{}
 			}
@@ -109,7 +109,7 @@ func (m *Plugin) generatePerSchema(data *codegen.Data) error {
 			}
 
 			resolver := Resolver{o, f, implementation}
-			fn := gqlToResolverName(data.Config.Resolver.Dir(), f.Position.Src.Name)
+			fn := gqlToResolverName(data.Config.Resolver.Dir(), f.Position.Src.Name, data.Config.Resolver.FilenameTemplate)
 			if files[fn] == nil {
 				files[fn] = &File{}
 			}
@@ -196,9 +196,12 @@ type Resolver struct {
 	Implementation string
 }
 
-func gqlToResolverName(base string, gqlname string) string {
+func gqlToResolverName(base string, gqlname, filenameTmpl string) string {
 	gqlname = filepath.Base(gqlname)
 	ext := filepath.Ext(gqlname)
-
-	return filepath.Join(base, strings.TrimSuffix(gqlname, ext)+".resolvers.go")
+	if filenameTmpl == "" {
+		filenameTmpl = "{name}.resolvers.go"
+	}
+	filename := strings.ReplaceAll(filenameTmpl, "{name}", strings.TrimSuffix(gqlname, ext))
+	return filepath.Join(base, filename)
 }

plugin/resolvergen/resolver_test.go

@@ -32,6 +32,8 @@ func TestLayoutSingleFile(t *testing.T) {
 
 func TestLayoutFollowSchema(t *testing.T) {
 	_ = syscall.Unlink("testdata/followschema/out/resolver.go")
+	_ = syscall.Unlink("testdata/followschema/out/schema.custom.go")
+	_ = syscall.Unlink("testdata/followschema/out/schema.resolvers.go")
 
 	cfg, err := config.LoadConfig("testdata/followschema/gqlgen.yml")
 	require.NoError(t, err)
@@ -56,6 +58,28 @@ func TestLayoutFollowSchema(t *testing.T) {
 	require.Contains(t, source, "// AUserHelperFunction implementation")
 }
 
+func TestLayoutFollowSchemaWithCustomFilename(t *testing.T) {
+	_ = syscall.Unlink("testdata/followschema/out/resolver.go")
+	_ = syscall.Unlink("testdata/followschema/out/schema.custom.go")
+	_ = syscall.Unlink("testdata/followschema/out/schema.resolvers.go")
+
+	cfg, err := config.LoadConfig("testdata/followschema/gqlgen.customfilename.yml")
+	require.NoError(t, err)
+	p := Plugin{}
+
+	require.NoError(t, cfg.Init())
+
+	data, err := codegen.BuildData(cfg)
+	if err != nil {
+		panic(err)
+	}
+
+	require.NoError(t, p.GenerateCode(data))
+	assertNoErrors(t, "github.com/99designs/gqlgen/plugin/resolvergen/testdata/followschema/out")
+
+	require.FileExists(t, "testdata/followschema/out/schema.custom.go")
+}
+
 func assertNoErrors(t *testing.T, pkg string) {
 	pkgs, err := packages.Load(&packages.Config{
 		Mode: packages.NeedName |

plugin/resolvergen/testdata/followschema/gqlgen.customfilename.yml

@@ -0,0 +1,16 @@
+schema:
+  - "testdata/schema.graphql"
+
+exec:
+  filename: testdata/singlefile/out/ignored.go
+model:
+  filename: testdata/singlefile/out/generated.go
+resolver:
+  type: CustomResolverType
+  layout: follow-schema
+  dir: testdata/followschema/out
+  filename_template: "{name}.custom.go"
+
+models:
+  Resolver:
+    model: github.com/99designs/gqlgen/plugin/resolvergen/testdata/singlefile/out.Resolver