introspection: __type

graphql_test.go

@@ -585,6 +585,26 @@ var tests = []struct {
 			}
 		`,
 	},
+
+	{
+		name:     "StarWarsIntrospection3",
+		schema:   starwars.Schema,
+		resolver: &starwars.Resolver{},
+		query: `
+			{
+				__type(name: "Droid") {
+					name
+				}
+			}
+		`,
+		result: `
+			{
+				"__type": {
+					"name": "Droid"
+				}
+			}
+		`,
+	},
 }
 
 func TestAll(t *testing.T) {

internal/exec/exec.go

@@ -278,7 +278,10 @@ func (e *objectExec) execSelectionSet(r *request, selSet *query.SelectionSet, re
 						}
 
 					case "__schema":
-						addResult(f.Alias, introspect(r, f.SelSet))
+						addResult(f.Alias, introspectSchema(r, f.SelSet))
+
+					case "__type":
+						addResult(f.Alias, introspectType(r, execValue(r, f.Arguments["name"]).(string), f.SelSet))
 
 					default:
 						fe, ok := e.fields[f.Name]

internal/exec/introspection.go

@@ -8,29 +8,41 @@ import (
 	"github.com/neelance/graphql-go/internal/schema"
 )
 
-var metaExec *Exec
+var metaSchema *schema.Schema
+var schemaExec iExec
+var typeExec iExec
 
 func init() {
-	metaSchema, err := schema.Parse(metaSchemaSrc, "")
+	var err error
+	metaSchema, err = schema.Parse(metaSchemaSrc, "")
 	if err != nil {
 		panic(err)
 	}
 
-	metaExec, err = Make(metaSchema, &schemaResolver{})
+	schemaExec, err = makeExec(metaSchema, metaSchema.Types["__Schema"], reflect.TypeOf(&schemaResolver{}), make(map[typeRefMapKey]*typeRefExec))
+	if err != nil {
+		panic(err)
+	}
+
+	typeExec, err = makeExec(metaSchema, metaSchema.Types["__Type"], reflect.TypeOf(&typeResolver{}), make(map[typeRefMapKey]*typeRefExec))
 	if err != nil {
 		panic(err)
 	}
 }
 
-func introspect(r *request, selSet *query.SelectionSet) interface{} {
-	return metaExec.exec(r, selSet, reflect.ValueOf(&schemaResolver{r.Schema}))
+func introspectSchema(r *request, selSet *query.SelectionSet) interface{} {
+	return schemaExec.exec(r, selSet, reflect.ValueOf(&schemaResolver{r.Schema}))
 }
 
-var metaSchemaSrc = `
-	schema {
-		query: __Schema
+func introspectType(r *request, name string, selSet *query.SelectionSet) interface{} {
+	t, ok := r.Schema.Types[name]
+	if !ok {
+		return nil
 	}
+	return typeExec.exec(r, selSet, reflect.ValueOf(&typeResolver{typ: t}))
+}
 
+var metaSchemaSrc = `
 	type __Schema {
 		types: [__Type!]!
 		queryType: __Type!
@@ -130,7 +142,7 @@ func (r *schemaResolver) Types() []*typeResolver {
 		}
 	}
 	addTypes(r.schema)
-	addTypes(metaExec.schema)
+	addTypes(metaSchema)
 	for _, name := range scalarTypeNames {
 		l = append(l, &typeResolver{scalar: name})
 	}