docs.ejabberd.im

Supporting and configuring specific XMPP Extensions in ejabberd


XMPP extensions support can be implemented in different ways in ejabberd. We have several cases:

  1. The extension must be implemented as a core feature of ejabberd. In that case, it may be supported as default and / or have configuration options in ejabberd config files.
  2. The extension can be optional and implemented as a module.
  3. The extension may additionally need to be enabled on the client stream to use it (For example MAM or stream management).

This section is here to help you understand how they are implemented XEP by XEP in ejabberd. We intend to explain what you can do in case you want to support a given XEP or if you want to make sure a specific Extension is disabled.

XEP-0004: Data Forms

Specification

XEP-0004: Data Forms

Implementation

ejabberd core

Comment

This extension is a general design principle for forms in XMPP. The principles are applied by all services, components and modules inside ejabberd.

Enabling / Disabling

As it is a general specification, it is used as default and cannot be disabled.

XEP-0012: Last Activity

Specification

XEP-0012: Last Activity

Implementation

Main ejabberd module: mod_last.erl

Comment

This extension is optional. It allows the server to send back information about when the user disconnected his last session.

It also allows to query the uptime of an ejabberd server.

Enabling

Add mod_last configuration in modules section of the configuration file.

It is enabled by default in ejabberd configuration template.

Disabling

Make sure mod_last is not defined or is commented out in ejabberd config modules section.

No side effect.

Module documentation

XEP-0013: Flexible Offline Message Retrieval

Specification

XEP-0013: Flexible Offline Message Retrieval

Implementation

Main ejabberd module: mod_offline.erl

Comment

This extension is active on server if mod_offline module is enabled on ejabberd.

However, it is not used by client automatically. Flexible offline message retrieval is enabled in the following cases:

Enabling

Add mod_offline configuration in modules section of the configuration file.

It is enabled and can be used by client if mod_offline is enabled. This is a module enabled by default in default ejabberd configuration file template.

Disabling

Make sure mod_offline is not defined or is commented out in ejabberd config modules section.

Side effect: It will disable all offline messages storage.

Module documentation