Merge pull request #36 from DHTMLX/v9.1.3

v9.1.3

Author: AlexKlimenkov

docs/api/config/date_format.md

@@ -30,24 +30,35 @@ If you want to use a custom format, you can either change this config, or redefi
 
 ## Loading dates in ISO format
 
-You can use ISO date format in Gantt. For this, you need to redefine functions that parse and serialize dates in Gantt:
+Since v9.1.3, Gantt automatically detects and parses ISO 8601 date strings. The `date_format` config is not needed for ISO strings - they are recognized and parsed directly. 
+
+When ISO dates are detected on input, they are serialized back as ISO strings automatically when passed to the [DataProcessor](guides/server-side.md). Date-only strings (e.g., `"2026-01-06"`) are serialized back as date-only strings, preserving the original format.
+
+The `date_format` config still applies to non-ISO date strings.
+
+:::tip Gantt v9.1.2 and earlier
+In versions before v9.1.3, ISO dates were not detected automatically. If you are using an older version, you need to override `parse_date` and `format_date` templates to handle ISO strings:
 
 ~~~js
-gantt.templates.parse_date = function(date) { 
+gantt.templates.parse_date = function(date) {
     return new Date(date);
 };
-gantt.templates.format_date = function(date) { 
+gantt.templates.format_date = function(date) {
     return date.toISOString();
 };
 ~~~
 
+:::
+
+For more details, see [Loading dates in ISO format](guides/loading.md#loading-dates-in-iso-format).
+
 ## Changing the date format dynamically
 
 If you need to change the date format dynamically, it is necessary to modify the [parse_date](api/template/parse_date.md) template in the following way:
 
 ~~~js
-var cfg = gantt.config;
-var strToDate = gantt.date.str_to_date(cfg.date_format, cfg.server_utc);
+const cfg = gantt.config;
+const strToDate = gantt.date.str_to_date(cfg.date_format, cfg.server_utc);
 
 gantt.templates.parse_date = function(date){
     return strToDate (date);

docs/api/other/date.md

@@ -197,17 +197,35 @@ var firstDay = gantt.date.month_start(new Date(2019, 05, 29, 14, 30));
 ---
 
 #### parseDate(date, format)
-Converts a string of the specified format to a Date object
+
+Converts a date string to a Date object. This method is called during [gantt.load()](api/method/load.md) and [gantt.parse()](api/method/parse.md) to parse task and link date properties.
 
 **Parameters**:
-- `date` - (string) - The date string
-- `format` - (string) - The date format (see guides/date-format.md)
+- `date` - (string) - The date string to parse
+- `format` - (string | function, optional) - A date format string (see [Date Format Specification](guides/date-format.md)) or a custom parser function `(dateStr) => Date`
 
 **Returns**: Date - The parsed date object
 
-**Example**:
+**Parsing logic** (since v9.1.3):
+
+1. **ISO 8601 check** - if the string matches an ISO 8601 pattern (e.g. `"2026-01-06"`, `"2026-01-06T10:30:00Z"`), it is parsed directly and `format` is not consulted. If the user has explicitly overridden `gantt.templates.parse_date`, ISO auto-detection is skipped and the user's function handles all parsing.
+2. **`format` argument** - if provided as a string, it is converted to a parser function via `gantt.date.str_to_date(format)`; if provided as a function, it is called directly
+3. **Fallback** - if no `format` is provided, the [parse_date](api/template/parse_date.md) template is used
+
+**Examples**:
 ~~~js
-var date = gantt.date.parseDate("29/06/2019","%d/%m/%Y"); //-> 29 June, 2019 00:00:00
+// with an explicit format string
+var date = gantt.date.parseDate("29/06/2019", "%d/%m/%Y");
+// -> 29 June, 2019 00:00:00
+
+// ISO string - parsed automatically, format is ignored
+var date2 = gantt.date.parseDate("2026-01-06T10:30:00Z");
+// -> 6 January, 2026 10:30:00 UTC
+
+// with a custom parser function
+var date3 = gantt.date.parseDate("Jan 6, 2026", function(str) {
+    return new Date(str);
+});
 ~~~
 
 ---

docs/api/template/format_date.md

@@ -34,17 +34,25 @@ Check [Date Format Specification](guides/date-format.md).
 
 ## Loading dates in ISO format
 
-You can use ISO date format in Gantt. For this, you need to redefine functions that parse and serialize dates in Gantt:
+Since v9.1.3, when ISO 8601 dates are detected on input, dates are serialized back as ISO strings automatically - unless you explicitly override this template. If you define a custom `format_date` function, it takes priority and is used for all dates, including ISO.
+
+:::tip Gantt v9.1.2 and earlier
+In versions before v9.1.3, ISO dates were not detected automatically. If you are using an older version, you need to override the templates to handle ISO strings:
 
 ~~~js
-gantt.templates.parse_date = function(date) { 
+gantt.templates.parse_date = function(date) {
     return new Date(date);
 };
-gantt.templates.format_date = function(date) { 
+gantt.templates.format_date = function(date) {
     return date.toISOString();
 };
 ~~~
 
+In v9.1.3+, these overrides are unnecessary for ISO dates.
+:::
+
+For more details, see [Loading dates in ISO format](guides/loading.md#loading-dates-in-iso-format).
+
 ## Changing the date format dynamically
 
 If you need to change the [date format](api/config/date_format.md) dynamically, it is necessary to modify the [parse_date](api/template/parse_date.md) template in the following way:

docs/api/template/parse_date.md

@@ -32,24 +32,33 @@ gantt.templates.parse_date = function(date){
 
 ### Details
 
-This function is called from **gantt.load()** or **gantt.parse()** call to parse the *start_date/end_date* properties of tasks, if they are provided in the string format. 
-This function can be redefined if you use a custom format that the default method can't parse. Check [Date Format Specification](guides/date-format.md).
+This function can be called from **gantt.load()** or **gantt.parse()** call to parse date properties of tasks, if they are provided in the string format. 
+
+This function can be redefined if you use a custom date format that the default method can't parse. Check [Date Format Specification](guides/date-format.md).
 
 [Read more about date objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date).
 
 ## Loading dates in ISO format
 
-You can use ISO date format in Gantt. For this, you need to redefine functions that parse and serialize dates in Gantt:
+Since v9.1.3, Gantt automatically detects and parses ISO 8601 date strings. A manual `parse_date` override is not needed for ISO dates. However, if you do override this template, your function takes priority - ISO auto-detection is skipped and your function handles all date strings.
+
+:::tip Gantt v9.1.2 and earlier
+In versions before v9.1.3, ISO dates were not detected automatically. If you are using an older version, you need to override this template to handle ISO strings:
 
 ~~~js
-gantt.templates.parse_date = function(date) { 
+gantt.templates.parse_date = function(date) {
     return new Date(date);
 };
-gantt.templates.format_date = function(date) { 
+gantt.templates.format_date = function(date) {
     return date.toISOString();
 };
 ~~~
 
+In v9.1.3+, these overrides are unnecessary for ISO dates.
+:::
+
+For more details, see [Loading dates in ISO format](guides/loading.md#loading-dates-in-iso-format).
+
 ### Related API
 - [parse](api/method/parse.md)
 - [load](api/method/load.md)

docs/guides/conversion-templates.md

@@ -8,3 +8,7 @@ sidebar_label: "Templates for Date Conversion"
 - [parse_date](api/template/parse_date.md) - converts date string into a Date object
 - [format_date](api/template/format_date.md) - converts a date object to a date string. Used to send data back to the server
 
+:::note
+Since v9.1.3, ISO 8601 dates are handled automatically without overriding these templates. See [Loading dates in ISO format](guides/loading.md#loading-dates-in-iso-format).
+:::
+

docs/guides/date-format.md

@@ -36,4 +36,3 @@ While specifying the format for dates you can use any character from the followi
 - **%A** - displays **AM** (for times from midnight until noon) and **PM** (for times from noon until midnight).
 
 For example, if you want to present 1st June 2019 as 01/06/2019, you should specify "%d/%m/%Y".
-

docs/guides/loading.md

@@ -164,7 +164,38 @@ The **end_date** has a higher priority than the **duration** parameter. If there
 
 ## Loading dates in ISO format
 
-You can use ISO date format in Gantt. For this, you need to redefine functions that parse and serialize dates in Gantt:
+Since v9.1.3, Gantt automatically detects and parses ISO 8601 date strings. No configuration is needed.
+
+Supported formats:
+
+- `2026-01-06` - date only
+- `2026-01-06T10:30:00` - date and time
+- `2026-01-06T10:30:00.000` - date and time with milliseconds
+- `2026-01-06T10:30:00.000Z` - UTC
+- `2026-01-06T10:30:00+02:00` - with timezone offset
+
+~~~js
+gantt.parse({
+    tasks: [
+        { id: 2, text: "Task #1", start_date: "2026-01-06T10:30:00Z", duration: 3 }
+    ],
+    links: []
+});
+// ISO dates are parsed automatically - no template overrides needed
+~~~
+
+When ISO dates are detected on input, they are serialized back as ISO strings automatically when passed to the [DataProcessor](guides/server-side.md). Date-only strings (e.g., `"2026-01-06"`) are serialized back as date-only strings, preserving the original format. If the input contains a mix of date-only and full datetime strings, all dates are serialized as full datetime.
+
+:::note
+Date-only strings (e.g., `"2026-01-06"`) are parsed as local midnight when `server_utc` is set to `false` (the default).
+:::
+
+:::note
+If you explicitly override `gantt.templates.parse_date` or `gantt.templates.format_date`, your functions take priority over ISO auto-detection and auto-serialization.
+:::
+
+:::tip Gantt v9.1.2 and earlier
+In versions before v9.1.3, ISO dates were not detected automatically. If you are using an older version, you need to override `parse_date` and `format_date` templates to handle ISO strings:
 
 ~~~js
 gantt.templates.parse_date = (date) => {
@@ -176,6 +207,9 @@ gantt.templates.format_date = (date) => {
 };
 ~~~
 
+In v9.1.3+, these templates are still used as the fallback for **non-ISO** date strings. See [gantt.date.parseDate()](api/other/date.md#parsedatedate-format) for the full parsing pipeline.
+:::
+
 ## Changing the date format dynamically
 
 If you need to change the [date format](api/config/date_format.md) dynamically, it is necessary to modify the [parse_date](api/template/parse_date.md) template in the following way:

docs/integrations/ai-tools/index.md

@@ -15,11 +15,11 @@ This section collects materials for using AI with DHTMLX Gantt in two ways:
 
 If you're using an AI app builder to generate or modify your UI, start here:
 
-- [Lovable AI](./lovable-ai/) — integrate DHTMLX [React Gantt](./../react/) into a Lovable-generated app and improve results using prompts, Knowledge Base, and MCP.
+- [Lovable AI](./lovable-ai/) - integrate DHTMLX [React Gantt](./../react/) into a Lovable-generated app and improve results using prompts, Knowledge Base, and MCP.
 
 ## MCP Server
 
-- [DHTMLX MCP Server](./mcp-server/) — connect an AI tool to up-to-date DHTMLX documentation and API reference.
+- [DHTMLX MCP Server](./mcp-server/) - connect an AI tool to up-to-date DHTMLX documentation and API reference.
 
 
 ## AI features inside your app

docs/integrations/react/state/jotai.md

@@ -246,13 +246,17 @@ export default function DemoJotai() {
 
 Let's configure the Gantt chart's templates which define date formatting and parsing for consistent data handling:
 
+:::note
+Since v9.1.3, Gantt automatically detects ISO date strings and these template overrides are no longer needed. They are shown here for compatibility with earlier Gantt versions. See [Loading dates in ISO format](guides/loading.md#loading-dates-in-iso-format).
+:::
+
 ~~~tsx
-const templates: ReactGanttProps['templates'] = useMemo(  
-  () => ({  
-    format_date: (date: Date) => date.toISOString(),  
-    parse_date: (value: string) => new Date(value),  
-  }),  
-  []  
+const templates: ReactGanttProps['templates'] = useMemo(
+  () => ({
+    format_date: (date: Date) => date.toISOString(),
+    parse_date: (value: string) => new Date(value),
+  }),
+  []
 );
 ~~~
 

docs/integrations/react/state/mobx.md

@@ -235,13 +235,17 @@ We wrap our component with `observer()` from `mobx-react-lite` to automatically
 
 Let's configure the Gantt chart's templates which define date formatting and parsing for consistent data handling:
 
+:::note
+Since v9.1.3, Gantt automatically detects ISO date strings and these template overrides are no longer needed. They are shown here for compatibility with earlier Gantt versions. See [Loading dates in ISO format](guides/loading.md#loading-dates-in-iso-format).
+:::
+
 ~~~tsx
-const templates: ReactGanttProps['templates'] = useMemo(  
-  () => ({  
-    format_date: (d) => d.toISOString(),  
-    parse_date: (s) => new Date(s),  
-  }),  
-  []  
+const templates: ReactGanttProps['templates'] = useMemo(
+  () => ({
+    format_date: (d) => d.toISOString(),
+    parse_date: (s) => new Date(s),
+  }),
+  []
 );
 ~~~