Json serialize types (#1378)

* Schema definitions now JSON serializeable

* Remove commented-out code

* Keep flow definitions with toJSON and inspect

* Factor out into utility function, change applyToStringTag naming to match

Also realized we weren't doing the same thing for directives, so fixed that as well.

Author: mjmahone

src/jsutils/defineToJSON.js

@@ -0,0 +1,17 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict
+ */
+
+/**
+ * The `applyToJSON()` function defines toJSON() and inspect() prototype
+ * methods which are aliases for toString().
+ */
+export default function applyToJSON(classObject: Class<any>): void {
+  classObject.prototype.toJSON = classObject.prototype.inspect =
+    classObject.prototype.toString;
+}

src/jsutils/applyToStringTag.js renamed to src/jsutils/defineToStringTag.js

@@ -8,7 +8,7 @@
  */
 
 import invariant from '../jsutils/invariant';
-import applyToStringTag from '../jsutils/applyToStringTag';
+import defineToStringTag from '../jsutils/defineToStringTag';
 
 type Location = {
   line: number,
@@ -44,4 +44,4 @@ export class Source {
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(Source);
+defineToStringTag(Source);

src/language/source.js

@@ -348,6 +348,26 @@ describe('Type System: Example', () => {
     expect(String(GraphQLList(GraphQLList(GraphQLInt)))).to.equal('[[Int]]');
   });
 
+  it('JSON stringifies simple types', () => {
+    expect(JSON.stringify(GraphQLInt)).to.equal('"Int"');
+    expect(JSON.stringify(BlogArticle)).to.equal('"Article"');
+    expect(JSON.stringify(InterfaceType)).to.equal('"Interface"');
+    expect(JSON.stringify(UnionType)).to.equal('"Union"');
+    expect(JSON.stringify(EnumType)).to.equal('"Enum"');
+    expect(JSON.stringify(InputObjectType)).to.equal('"InputObject"');
+    expect(JSON.stringify(GraphQLNonNull(GraphQLInt))).to.equal('"Int!"');
+    expect(JSON.stringify(GraphQLList(GraphQLInt))).to.equal('"[Int]"');
+    expect(JSON.stringify(GraphQLNonNull(GraphQLList(GraphQLInt)))).to.equal(
+      '"[Int]!"',
+    );
+    expect(JSON.stringify(GraphQLList(GraphQLNonNull(GraphQLInt)))).to.equal(
+      '"[Int!]"',
+    );
+    expect(JSON.stringify(GraphQLList(GraphQLList(GraphQLInt)))).to.equal(
+      '"[[Int]]"',
+    );
+  });
+
   it('identifies input types', () => {
     const expected = [
       [GraphQLInt, true],

src/type/__tests__/definition-test.js

@@ -7,7 +7,8 @@
  * @flow strict
  */
 
-import applyToStringTag from '../jsutils/applyToStringTag';
+import defineToJSON from '../jsutils/defineToJSON';
+import defineToStringTag from '../jsutils/defineToStringTag';
 import instanceOf from '../jsutils/instanceOf';
 import inspect from '../jsutils/inspect';
 import invariant from '../jsutils/invariant';
@@ -349,11 +350,11 @@ export function GraphQLList(ofType) {
   }
 }
 
-// Also provide toJSON and inspect aliases for toString.
-const listProto: any = GraphQLList.prototype;
-listProto.toString = listProto.toJSON = listProto.inspect = function toString() {
+// Need to cast through any to alter the prototype.
+(GraphQLList.prototype: any).toString = function toString() {
   return '[' + String(this.ofType) + ']';
 };
+defineToJSON(GraphQLList);
 
 /**
  * Non-Null Type Wrapper
@@ -390,11 +391,11 @@ export function GraphQLNonNull(ofType) {
   }
 }
 
-// Also provide toJSON and inspect aliases for toString.
-const nonNullProto: any = GraphQLNonNull.prototype;
-nonNullProto.toString = nonNullProto.toJSON = nonNullProto.inspect = function toString() {
+// Need to cast through any to alter the prototype.
+(GraphQLNonNull.prototype: any).toString = function toString() {
   return String(this.ofType) + '!';
 };
+defineToJSON(GraphQLNonNull);
 
 /**
  * These types wrap and modify other types
@@ -579,17 +580,11 @@ export class GraphQLScalarType {
   toString(): string {
     return this.name;
   }
-
-  toJSON: () => string;
-  inspect: () => string;
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLScalarType);
-
-// Also provide toJSON and inspect aliases for toString.
-GraphQLScalarType.prototype.toJSON = GraphQLScalarType.prototype.inspect =
-  GraphQLScalarType.prototype.toString;
+defineToStringTag(GraphQLScalarType);
+defineToJSON(GraphQLScalarType);
 
 export type GraphQLScalarTypeConfig<TInternal, TExternal> = {
   name: string,
@@ -684,17 +679,11 @@ export class GraphQLObjectType {
   toString(): string {
     return this.name;
   }
-
-  toJSON: () => string;
-  inspect: () => string;
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLObjectType);
-
-// Also provide toJSON and inspect aliases for toString.
-GraphQLObjectType.prototype.toJSON = GraphQLObjectType.prototype.inspect =
-  GraphQLObjectType.prototype.toString;
+defineToStringTag(GraphQLObjectType);
+defineToJSON(GraphQLObjectType);
 
 function defineInterfaces(
   type: GraphQLObjectType,
@@ -936,17 +925,11 @@ export class GraphQLInterfaceType {
   toString(): string {
     return this.name;
   }
-
-  toJSON: () => string;
-  inspect: () => string;
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLInterfaceType);
-
-// Also provide toJSON and inspect aliases for toString.
-GraphQLInterfaceType.prototype.toJSON = GraphQLInterfaceType.prototype.inspect =
-  GraphQLInterfaceType.prototype.toString;
+defineToStringTag(GraphQLInterfaceType);
+defineToJSON(GraphQLInterfaceType);
 
 export type GraphQLInterfaceTypeConfig<TSource, TContext> = {
   name: string,
@@ -1019,17 +1002,11 @@ export class GraphQLUnionType {
   toString(): string {
     return this.name;
   }
-
-  toJSON: () => string;
-  inspect: () => string;
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLUnionType);
-
-// Also provide toJSON and inspect aliases for toString.
-GraphQLUnionType.prototype.toJSON = GraphQLUnionType.prototype.inspect =
-  GraphQLUnionType.prototype.toString;
+defineToStringTag(GraphQLUnionType);
+defineToJSON(GraphQLUnionType);
 
 function defineTypes(
   unionType: GraphQLUnionType,
@@ -1138,17 +1115,11 @@ export class GraphQLEnumType /* <T> */ {
   toString(): string {
     return this.name;
   }
-
-  toJSON: () => string;
-  inspect: () => string;
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLEnumType);
-
-// Also provide toJSON and inspect aliases for toString.
-GraphQLEnumType.prototype.toJSON = GraphQLEnumType.prototype.inspect =
-  GraphQLEnumType.prototype.toString;
+defineToStringTag(GraphQLEnumType);
+defineToJSON(GraphQLEnumType);
 
 function defineEnumValues(
   type: GraphQLEnumType,
@@ -1275,19 +1246,11 @@ export class GraphQLInputObjectType {
   toString(): string {
     return this.name;
   }
-
-  toJSON: () => string;
-  inspect: () => string;
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLInputObjectType);
-
-// Also provide toJSON and inspect aliases for toString.
-GraphQLInputObjectType.prototype.toJSON =
-  GraphQLInputObjectType.prototype.toString;
-GraphQLInputObjectType.prototype.inspect =
-  GraphQLInputObjectType.prototype.toString;
+defineToStringTag(GraphQLInputObjectType);
+defineToJSON(GraphQLInputObjectType);
 
 export type GraphQLInputObjectTypeConfig = {
   name: string,

src/type/definition.js

@@ -13,7 +13,8 @@ import type {
 } from './definition';
 import { GraphQLNonNull } from './definition';
 import { GraphQLString, GraphQLBoolean } from './scalars';
-import applyToStringTag from '../jsutils/applyToStringTag';
+import defineToStringTag from '../jsutils/defineToStringTag';
+import defineToJSON from '../jsutils/defineToJSON';
 import instanceOf from '../jsutils/instanceOf';
 import invariant from '../jsutils/invariant';
 import type { DirectiveDefinitionNode } from '../language/ast';
@@ -75,10 +76,15 @@ export class GraphQLDirective {
       });
     }
   }
+
+  toString(): string {
+    return '@' + this.name;
+  }
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLDirective);
+defineToStringTag(GraphQLDirective);
+defineToJSON(GraphQLDirective);
 
 export type GraphQLDirectiveConfig = {
   name: string,

src/type/directives.js

@@ -33,7 +33,7 @@ import {
 import type { GraphQLError } from '../error/GraphQLError';
 import inspect from '../jsutils/inspect';
 import { __Schema } from './introspection';
-import applyToStringTag from '../jsutils/applyToStringTag';
+import defineToStringTag from '../jsutils/defineToStringTag';
 import find from '../jsutils/find';
 import instanceOf from '../jsutils/instanceOf';
 import invariant from '../jsutils/invariant';
@@ -233,7 +233,7 @@ export class GraphQLSchema {
 }
 
 // Conditionally apply `[Symbol.toStringTag]` if `Symbol`s are supported
-applyToStringTag(GraphQLSchema);
+defineToStringTag(GraphQLSchema);
 
 type TypeMap = ObjMap<GraphQLNamedType>;