ISO date format support (#621)

* ISO date format support

* Remove yarn.lock

* Revert DATEONLY to String and add DateType to src/index

* Missed the DATEONLY test description on revert.

Author: RichAyotte

src/index.js

@@ -12,4 +12,5 @@ module.exports = {
   createConnectionResolver: require('./relay').createConnectionResolver,
   createNodeInterface: require('./relay').createNodeInterface,
   JSONType: require('./types/jsonType'),
+  DateType: require('./types/DateType'),
 };

src/typeMapper.js

@@ -1,11 +1,13 @@
 import {
-   GraphQLInt,
-   GraphQLString,
-   GraphQLBoolean,
-   GraphQLFloat,
-   GraphQLEnumType,
-   GraphQLList
- } from 'graphql';
+  GraphQLInt,
+  GraphQLString,
+  GraphQLBoolean,
+  GraphQLFloat,
+  GraphQLEnumType,
+  GraphQLList,
+} from 'graphql';
+
+import DateType from './types/dateType';
 import JSONType from './types/jsonType';
 import _ from 'lodash';
 
@@ -18,7 +20,6 @@ export function mapType(mapFunc) {
   customTypeMapper = mapFunc;
 }
 
-
 /**
  * Checks the type of the sequelize data type and
  * returns the corresponding type in GraphQL
@@ -68,11 +69,14 @@ export function toGraphQL(sequelizeType, sequelizeTypes) {
   if (sequelizeType instanceof FLOAT ||
       sequelizeType instanceof DOUBLE) return GraphQLFloat;
 
+  if (sequelizeType instanceof DATE) {
+    return DateType;
+  }
+
   if (sequelizeType instanceof CHAR ||
       sequelizeType instanceof STRING ||
       sequelizeType instanceof TEXT ||
       sequelizeType instanceof UUID ||
-      sequelizeType instanceof DATE ||
       sequelizeType instanceof DATEONLY ||
       sequelizeType instanceof TIME ||
       sequelizeType instanceof BIGINT ||

src/types/dateType.js

@@ -0,0 +1,49 @@
+import {
+  GraphQLScalarType
+} from 'graphql';
+
+/**
+ * A special custom Scalar type for Dates that converts to a ISO formatted string
+ * @param {String} options.name:
+ * @param {String} options.description:
+ * @param {Date} options.serialize(d)
+ * @param {String} parseValue(value)
+ * @param {Object} parseLiteral(ast)
+ */
+export default new GraphQLScalarType({
+  name: 'Date',
+  description: 'A special custom Scalar type for Dates that converts to a ISO formatted string ',
+  /**
+   * serialize
+   * @param  {Date} d Date obj
+   * @return {String} Serialised date object
+   */
+  serialize(d) {
+    if (!d) {
+      return null;
+    }
+
+    if (d instanceof Date) {
+      return d.toISOString();
+    }
+    return d;
+  },
+  /**
+   * parseValue
+   * @param  {String} value date string
+   * @return {Date}   Date object
+   */
+  parseValue(value) {
+    try {
+      if (!value) {
+        return null;
+      }
+      return new Date(value);
+    } catch (e) {
+      return null;
+    }
+  },
+  parseLiteral(ast) {
+    return new Date(ast.value);
+  }
+});

test/unit/attributeFields.test.js

@@ -3,9 +3,11 @@
 import {expect} from 'chai';
 import Sequelize from 'sequelize';
 import attributeFields from '../../src/attributeFields';
+import DateType from '../../src/types/dateType';
 
 import { sequelize } from '../support/helper';
 
+
 import {
   GraphQLString,
   GraphQLInt,
@@ -116,7 +118,7 @@ describe('attributeFields', function () {
 
     expect(fields.virtualBoolean.type).to.equal(GraphQLBoolean);
 
-    expect(fields.date.type).to.equal(GraphQLString);
+    expect(fields.date.type).to.equal(DateType);
 
     expect(fields.time.type).to.equal(GraphQLString);
 

test/unit/defaultArgs.test.js

@@ -4,6 +4,7 @@
 import {expect} from 'chai';
 import Sequelize from 'sequelize';
 import defaultArgs from '../../src/defaultArgs';
+import DateType from '../../src/types/dateType';
 
 import { sequelize } from '../support/helper';
 
@@ -76,7 +77,7 @@ describe('defaultArgs', function () {
     args = defaultArgs(Model);
 
     expect(args.userId.type).to.equal(GraphQLInt);
-    expect(args.timestamp.type).to.equal(GraphQLString);
+    expect(args.timestamp.type).to.equal(DateType);
   });
 
   describe('will have an "where" argument', function () {

test/unit/typeMapper.test.js

@@ -1,6 +1,7 @@
 import { expect } from 'chai';
 import { mapType, toGraphQL } from '../../src/typeMapper';
 import JSONType from '../../src/types/jsonType';
+import DateType from '../../src/types/dateType';
 
 import Sequelize from 'sequelize';
 
@@ -87,8 +88,8 @@ describe('typeMapper', () => {
   });
 
   describe('DATE', function () {
-    it('should map to GraphQLString', function () {
-      expect(toGraphQL(new DATE(), Sequelize)).to.equal(GraphQLString);
+    it('should map to DateType', function () {
+      expect(toGraphQL(new DATE(), Sequelize)).to.equal(DateType);
     });
   });