feat: respect "default" values when creating new elements in an array

Initialize new array elements with their default values.
Fixes default value returned for string schemas with a date format.

Fixes #2195

packages/core/src/util/renderer.ts

@@ -57,7 +57,7 @@ import { createLabelDescriptionFrom } from './label';
 import type { CombinatorKeyword } from './combinators';
 import { moveDown, moveUp } from './array';
 import type { AnyAction, Dispatch } from './type';
-import { Resolve } from './util';
+import { Resolve, convertDateToString } from './util';
 import { composePaths, composeWithUi } from './path';
 import { CoreActions, update } from '../actions';
 import type { ErrorObject } from 'ajv';
@@ -78,6 +78,7 @@ import {
   arrayDefaultTranslations,
   ArrayTranslations,
 } from '../i18n/arrayTranslations';
+import cloneDeep from 'lodash/cloneDeep';
 
 const isRequired = (
   schema: JsonSchema,
@@ -137,19 +138,22 @@ export const showAsRequired = (
 };
 
 /**
- * Create a default value based on the given scheam.
+ * Create a default value based on the given schema.
  * @param schema the schema for which to create a default value.
  * @returns {any}
  */
 export const createDefaultValue = (schema: JsonSchema) => {
+  if (schema.default !== undefined) {
+    return extractDefaults(schema);
+  }
   switch (schema.type) {
     case 'string':
       if (
         schema.format === 'date-time' ||
         schema.format === 'date' ||
         schema.format === 'time'
       ) {
-        return new Date();
+        return convertDateToString(new Date(), schema.format);
       }
       return '';
     case 'integer':
@@ -161,11 +165,32 @@ export const createDefaultValue = (schema: JsonSchema) => {
       return [];
     case 'null':
       return null;
+    case 'object':
+      return extractDefaults(schema);
     default:
       return {};
   }
 };
 
+/**
+ * Returns the default value defined in the given schema.
+ * @param schema the schema for which to create a default value.
+ * @returns {any}
+ */
+export const extractDefaults = (schema: JsonSchema) => {
+  if (schema.type === 'object' && schema.default === undefined) {
+    const result: { [key: string]: any } = {};
+    for (const key in schema.properties) {
+      const property = schema.properties[key];
+      if (property.default !== undefined) {
+        result[key] = cloneDeep(property.default);
+      }
+    }
+    return result;
+  }
+  return cloneDeep(schema.default);
+};
+
 /**
  * Whether an element's description should be hidden.
  *

packages/core/src/util/util.ts

@@ -33,6 +33,49 @@ import { composePaths, toDataPathSegments } from './path';
 import { isEnabled, isVisible } from './runtime';
 import type Ajv from 'ajv';
 
+/**
+ * Returns the string representation of the given date. The format of the output string can be specified:
+ * - 'date' for a date-only string (YYYY-MM-DD),
+ * - 'time' for a time-only string (HH:mm:ss), or
+ * - 'date-time' for a full date-time string in ISO format (YYYY-MM-DDTHH:mm:ss.sssZ).
+ * If no format is specified, the full date-time ISO string is returned by default.
+ *
+ * @returns {string} A string representation of the date in the specified format.
+ *
+ * @example
+ * // returns '2023-11-09'
+ * convertDateToString(new Date('2023-11-09T14:22:54.131Z'), 'date');
+ *
+ * @example
+ * // returns '14:22:54'
+ * convertDateToString(new Date('2023-11-09T14:22:54.131Z'), 'time');
+ *
+ * @example
+ * // returns '2023-11-09T14:22:54.131Z'
+ * convertDateToString(new Date('2023-11-09T14:22:54.131Z'), 'date-time');
+ *
+ * @example
+ * // returns '2023-11-09T14:22:54.131Z'
+ * convertDateToString(new Date('2023-11-09T14:22:54.131Z'));
+ */
+export const convertDateToString = (
+  date: Date,
+  format?: 'date' | 'time' | 'date-time'
+): string => {
+  //e.g. '2023-11-09T14:22:54.131Z'
+  const dateString = date.toISOString();
+  if (format === 'date-time') {
+    return dateString;
+  } else if (format === 'date') {
+    // e.g. '2023-11-09'
+    return dateString.split('T')[0];
+  } else if (format === 'time') {
+    //e.g. '14:22:54'
+    return dateString.split('T')[1].split('.')[0];
+  }
+  return dateString;
+};
+
 /**
  * Escape the given string such that it can be used as a class name,
  * i.e. hashes and slashes will be replaced.

packages/core/test/util/renderer.test.ts

@@ -70,6 +70,7 @@ import { createAjv } from '../../src/util/validator';
 import { JsonSchema7 } from '../../src/models/jsonSchema7';
 import { defaultJsonFormsI18nState } from '../../src/reducers/i18n';
 import { i18nJsonSchema } from '../../src/i18n/i18nTypes';
+import { convertDateToString } from '../../src/util';
 
 const middlewares: Redux.Middleware[] = [];
 const mockStore = configureStore<JsonFormsState>(middlewares);
@@ -494,29 +495,26 @@ test('mapDispatchToControlProps', (t) => {
 });
 
 test('createDefaultValue', (t) => {
-  t.true(
-    _.isDate(
-      createDefaultValue({
-        type: 'string',
-        format: 'date',
-      })
-    )
+  t.is(
+    createDefaultValue({
+      type: 'string',
+      format: 'date',
+    }),
+    convertDateToString(new Date(), 'date')
   );
-  t.true(
-    _.isDate(
-      createDefaultValue({
-        type: 'string',
-        format: 'date-time',
-      })
-    )
+  t.regex(
+    createDefaultValue({
+      type: 'string',
+      format: 'date-time',
+    }),
+    /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z$/
   );
-  t.true(
-    _.isDate(
-      createDefaultValue({
-        type: 'string',
-        format: 'time',
-      })
-    )
+  t.regex(
+    createDefaultValue({
+      type: 'string',
+      format: 'time',
+    }),
+    /^\d{2}:\d{2}:\d{2}$/
   );
   t.is(createDefaultValue({ type: 'string' }), '');
   t.is(createDefaultValue({ type: 'number' }), 0);
@@ -526,6 +524,50 @@ test('createDefaultValue', (t) => {
   t.is(createDefaultValue({ type: 'null' }), null);
   t.deepEqual(createDefaultValue({ type: 'object' }), {});
   t.deepEqual(createDefaultValue({ type: 'something' }), {});
+
+  // defaults:
+  t.deepEqual(
+    createDefaultValue({
+      type: 'string',
+      default: '2023-10-10',
+    }),
+    '2023-10-10'
+  );
+  t.is(
+    createDefaultValue({ type: 'string', default: 'excellent' }),
+    'excellent'
+  );
+  t.is(createDefaultValue({ type: 'number', default: 10 }), 10);
+  t.is(createDefaultValue({ type: 'boolean', default: true }), true);
+  t.is(createDefaultValue({ type: 'integer', default: 11 }), 11);
+  t.deepEqual(createDefaultValue({ type: 'array', default: ['a', 'b', 'c'] }), [
+    'a',
+    'b',
+    'c',
+  ]);
+  t.deepEqual(createDefaultValue({ type: 'object', default: { foo: 'bar' } }), {
+    foo: 'bar',
+  });
+  t.deepEqual(
+    createDefaultValue({
+      type: 'object',
+      properties: {
+        string1: { type: 'string', default: 'excellent' },
+        string2: { type: 'string' },
+        number: { type: 'number', default: 10 },
+        int: { type: 'integer', default: 11 },
+        bool: { type: 'boolean', default: true },
+        array: { type: 'array', default: ['a', 'b', 'c'] },
+      },
+    }),
+    {
+      string1: 'excellent',
+      number: 10,
+      int: 11,
+      bool: true,
+      array: ['a', 'b', 'c'],
+    }
+  );
 });
 
 test(`mapStateToJsonFormsRendererProps should use registered UI schema given ownProps schema`, (t) => {

packages/examples/src/examples/arrays-with-defaults.ts

@@ -0,0 +1,101 @@
+/*
+  The MIT License
+  
+  Copyright (c) 2023 EclipseSource Munich
+  https://github.com/eclipsesource/jsonforms
+  
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the 'Software'), to deal
+  in the Software without restriction, including without limitation the rights
+  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+  copies of the Software, and to permit persons to whom the Software is
+  furnished to do so, subject to the following conditions:
+  
+  The above copyright notice and this permission notice shall be included in
+  all copies or substantial portions of the Software.
+  
+  THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+  THE SOFTWARE.
+*/
+import { convertDateToString } from '@jsonforms/core';
+import { registerExamples } from '../register';
+
+export const schema = {
+  type: 'object',
+  properties: {
+    objectArray: {
+      type: 'array',
+      items: {
+        type: 'object',
+        properties: {
+          name: {
+            type: 'string',
+            default: 'foo',
+          },
+          name_noDefault: {
+            type: 'string',
+          },
+          description: {
+            type: 'string',
+            default: 'bar',
+          },
+          done: {
+            type: 'boolean',
+            default: false,
+          },
+          rating: {
+            type: 'integer',
+            default: 5,
+          },
+          cost: {
+            type: 'number',
+            default: 5.5,
+          },
+          date: {
+            type: 'string',
+            format: 'date',
+            default: convertDateToString(new Date(), 'date'),
+          },
+        },
+      },
+    },
+    stringArray: {
+      type: 'array',
+      items: {
+        type: 'string',
+        default: '123',
+      },
+    },
+  },
+};
+
+export const uischema = {
+  type: 'VerticalLayout',
+  elements: [
+    {
+      type: 'Control',
+      scope: '#/properties/objectArray',
+    },
+    {
+      type: 'Control',
+      scope: '#/properties/stringArray',
+    },
+  ],
+};
+
+export const data = {};
+
+registerExamples([
+  {
+    name: 'array-with-defaults',
+    label: 'Array with defaults',
+    data,
+    schema,
+    uischema,
+  },
+]);

packages/examples/src/index.ts

@@ -35,6 +35,7 @@ import * as arrayWithDetail from './examples/arrays-with-detail';
 import * as arrayWithDetailAndRule from './examples/arrays-with-detail-and-rule';
 import * as arrayWithCustomChildLabel from './examples/arrays-with-custom-element-label';
 import * as arrayWithSorting from './examples/arrays-with-sorting';
+import * as arrayWithDefaults from './examples/arrays-with-defaults';
 import * as stringArray from './examples/stringArray';
 import * as categorization from './examples/categorization';
 import * as stepper from './examples/categorization-stepper';
@@ -125,4 +126,5 @@ export {
   conditionalSchemaComposition,
   additionalErrors,
   issue_1884,
+  arrayWithDefaults,
 };