> ## Documentation Index
> Fetch the complete documentation index at: https://docs.aseeflow.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Date Format

The REST API uses the default date format `yyyy-MM-dd'T'HH:mm:ss.SSSZ`, which
represents a date with milliseconds and timezone information, e.g.,
`2016-01-25T13:33:42.165+0100`.

If you add a date as a GET request parameter, remember the URL encoding, e.g. `2016-01-25T13:33:42.165%2b0100`.

## Custom Date Format

A custom date format can be configured in the `web.xml`
file of the REST API. To do so, the ServletContextListener
`CustomJacksonDateFormatListener` has to be added. The custom date format
can be specified by the context parameter
`org.camunda.bpm.engine.rest.jackson.dateFormat`.

For example, if the date format should not contain milliseconds and timezone
information (`yyyy-MM-dd'T'HH:mm:ss`) the following configuration can be
used.

To achieve this, you can edit the `WEB-INF/web.xml` file as follows:

```xml theme={null}
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">

  <!-- ... -->

  <listener>
    <listener-class>
      org.camunda.bpm.engine.rest.CustomJacksonDateFormatListener
    </listener-class>
  </listener>

  <context-param>
    <param-name>org.camunda.bpm.engine.rest.jackson.dateFormat</param-name>
    <param-value>yyyy-MM-dd'T'HH:mm:ss</param-value>
  </context-param>

  <!-- ... -->
</web-app>
```

With this configuration the REST API will return dates with millisecond
precision and timezone information. Also, new dates with milliseconds and timezone information
can be submitted to the REST API without losing these details.

<Warning>
  **Webapps compatibility**

  Be aware that, to be able to use the ASEE Flow webapps, the date format must correspond to the following:

  `yyyy-MM-dd['T'HH:mm[:ss[.SSS[Z]]]]`
</Warning>