add stub generation plugin

codegen/field.go

@@ -325,10 +325,7 @@ func (f *Field) ResolverType() string {
 }
 
 func (f *Field) ShortResolverDeclaration() string {
-	if !f.IsResolver {
-		return ""
-	}
-	res := fmt.Sprintf("%s(ctx context.Context", f.GoFieldName)
+	res := "(ctx context.Context"
 
 	if !f.Object.Root {
 		res += fmt.Sprintf(", obj *%s", templates.CurrentImports.LookupType(f.Object.Type))

codegen/generated!.gotpl

@@ -60,7 +60,9 @@ type ComplexityRoot struct {
 	{{ if $object.HasResolvers }}
 		type {{$object.Name}}Resolver interface {
 		{{ range $field := $object.Fields -}}
-			{{ $field.ShortResolverDeclaration }}
+			{{- if $field.IsResolver }}
+				{{- $field.GoFieldName}}{{ $field.ShortResolverDeclaration }}
+			{{- end }}
 		{{ end }}
 		}
 	{{- end }}

plugin/resolvergen/resolver.gotpl

@@ -31,7 +31,7 @@ type {{.ResolverType}} struct {}
 
 		{{ range $field := $object.Fields -}}
 			{{- if $field.IsResolver -}}
-			func (r *{{lcFirst $object.Name}}Resolver) {{ $field.ShortResolverDeclaration }} {
+			func (r *{{lcFirst $object.Name}}Resolver) {{$field.GoFieldName}}{{ $field.ShortResolverDeclaration }} {
 				panic("not implemented")
 			}
 			{{ end -}}

plugin/stubgen/stubs.go

@@ -0,0 +1,39 @@
+package stubgen
+
+import (
+	"github.com/99designs/gqlgen/codegen"
+	"github.com/99designs/gqlgen/codegen/templates"
+	"github.com/99designs/gqlgen/plugin"
+)
+
+func New(filename string, typename string) plugin.Plugin {
+	return &Plugin{filename: filename, typeName: typename}
+}
+
+type Plugin struct {
+	filename string
+	typeName string
+}
+
+var _ plugin.CodeGenerator = &Plugin{}
+
+func (m *Plugin) Name() string {
+	return "stubgen"
+}
+func (m *Plugin) GenerateCode(data *codegen.Data) error {
+	return templates.Render(templates.Options{
+		PackageName: data.Config.Resolver.Package,
+		Filename:    m.filename,
+		Data: &ResolverBuild{
+			Data:     data,
+			TypeName: m.typeName,
+		},
+		GeneratedHeader: false,
+	})
+}
+
+type ResolverBuild struct {
+	*codegen.Data
+
+	TypeName string
+}

plugin/stubgen/stubs.gotpl

@@ -0,0 +1,57 @@
+{{ reserveImport "context"  }}
+{{ reserveImport "fmt"  }}
+{{ reserveImport "io"  }}
+{{ reserveImport "strconv"  }}
+{{ reserveImport "time"  }}
+{{ reserveImport "sync"  }}
+{{ reserveImport "errors"  }}
+{{ reserveImport "bytes"  }}
+
+{{ reserveImport "github.com/99designs/gqlgen/handler" }}
+{{ reserveImport "github.com/vektah/gqlparser" }}
+{{ reserveImport "github.com/vektah/gqlparser/ast" }}
+{{ reserveImport "github.com/99designs/gqlgen/graphql" }}
+{{ reserveImport "github.com/99designs/gqlgen/graphql/introspection" }}
+
+{{ $root := . }}
+
+type {{$root.TypeName}} struct {
+	{{ range $object := .Objects }}
+		{{- if $object.HasResolvers }}
+			{{$object.Name}}Resolver struct {
+				{{- range $field := $object.Fields }}
+					{{- if $field.IsResolver }}
+						{{- $field.GoFieldName}} func{{ $field.ShortResolverDeclaration }}
+					{{ end }}
+				{{- end }}
+			}
+		{{- end }}
+	{{- end }}
+}
+
+{{ range $object := .Objects -}}
+	{{- if $object.HasResolvers -}}
+		func (r *{{$.TypeName}}) {{$object.Name}}() {{ $object.ResolverInterface | ref }} {
+			return &{{lcFirst $root.TypeName}}{{$object.Name}}{r}
+		}
+	{{ end -}}
+{{ end }}
+
+{{ range $object := .Objects -}}
+	{{- if $object.HasResolvers -}}
+		type {{lcFirst $root.TypeName}}{{$object.Name}} struct { *{{$root.TypeName}}  }
+
+		{{ range $field := $object.Fields -}}
+			{{- if $field.IsResolver -}}
+				func (r *{{lcFirst $root.TypeName}}{{$object.Name}}) {{$field.GoFieldName}}{{ $field.ShortResolverDeclaration }} {
+					return r.{{$object.Name}}Resolver.{{$field.GoFieldName}}(ctx,
+						{{- if not $object.Root }}obj,{{end -}}
+						{{- range $arg := $field.Args}}
+							{{$arg.VarName}},
+						{{- end }}
+					)
+				}
+			{{ end -}}
+		{{ end -}}
+	{{ end -}}
+{{ end }}

testdata/gqlgen.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/99designs/gqlgen"
 	"github.com/99designs/gqlgen/codegen/config"
+	"github.com/99designs/gqlgen/plugin/stubgen"
 )
 
 func main() {
@@ -22,7 +23,7 @@ func main() {
 		os.Exit(2)
 	}
 
-	err = gqlgen.Generate(cfg)
+	err = gqlgen.Generate(cfg, gqlgen.AddPlugin(stubgen.New(cfg.Exec.Dir()+"/stubs.go", "Stub")))
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err.Error())
 		os.Exit(3)