---
name: "Lemonldap::NG::Common::MessageBroker"
section: "3pm"
platform: "linux"
package: "liblemonldap-ng-common-perl"
version: "2.21.2+ds-1+deb13u3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Lemonldap::NG::Common::MessageBroker"
---

# Lemonldap::NG::Common::MessageBroker(3pm)

Doc for MessageBroker classes

## NAME

Lemonldap::NG::Common::MessageBroker - Doc for MessageBroker classes

## DESCRIPTION

Starting from 2.20.0, Lemonldap::NG dispatches its events to other nodes using messages sent by a *Lemonldap::NG::Common::MessageBroker* sub class.

By default, only 2 kind of messages are dispatched:

- •

  **configuration updates**: each time a configuration is saved.

  Note that default broker also adds such messages regularly following the `"chectTime"` value *(because it's not a real evant pub/sub system)*. This keep previous behavior.

- •

  **session logouts**: whenever a session is terminated before it expires *(either because the user logged out or by action of an administrator)*.

  Default broker just push this information on local node. Other will discover the end of session after local cache expiration *(max 10 minutes)*.

By default, LLNG uses only one channel, defined in `"eventQueueName"` configuration parameter.

During initialization, LLNG creates always 2 distinct objects:

- •

  **a reader** which calls `subscribe()` for each channel and then check for messages every 5 seconds

- •

  **a writer** which send messages on channels

The Lemonldap::NG::Hanlder::Main::MsgActions class contains actions to be launched when a message enter in the main events channel.

## METHODS

Except `"applyConf"`, all this methods must exist in a Message Broker.

### new

Constructor. Arguments:

- •

  **$class**: class name

- •

  **$conf**: current LLNG configuration

- •

  **$logger**: a Lemonldap::NG::Common logger

### publish

Method to insert an message. Arguments:

- •

  **$self**

- •

  **$channel**: the channel name

- •

  **$msg**: a hash reference containing the message

### subscribe

Methode called during LLNG initialization for its message reader object. Arguments:

- •

  **$self**

- •

  **$channel**: the channel name

### getNextMessage

Non blocking method that return a message in the given channel if one exists. Arguments:

- •

  **$self**

- •

  **$channel**: the channel name

### waitForNextMessage

Blocking method that waits for a message in the given channel and return it. Arguments:

- •

  **$self**

- •

  **$channel**: the channel name

### applyConf

Optional method called after configuration save. It is used only with default message broker to launch previous behavior: call all "reload URLs".

## MESSAGE FORMAT

A message is a HASH reference. A message in the main event channel must contain a key "**action**". This key is used by Lemonldap::NG::Hanlder::Main::MsgActions to launch the corresponding method.

- •

  **Configuration update**

  ```
    {
      action => 'newConf'
    }
  ```

- •

  **Session end**

  ```
    {
      action => 'unlog',
      id => '<configuration id to be removed from local cache>'
    }
  ```

## SEE ALSO

Lemonldap::NG::Manager, Lemonldap::NG::Portal, Lemonldap::NG::Handler

## AUTHORS

- LemonLDAP::NG team \<http://lemonldap-ng.org/team\>

  ## BUG REPORT

Use OW2 system to report bug or ask for features: \<https://gitlab.ow2.org/lemonldap-ng/lemonldap-ng/issues\>

## DOWNLOAD

Lemonldap::NG is available at \<https://lemonldap-ng.org/download\>

## COPYRIGHT AND LICENSE

See COPYING file for details.

This library is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program.  If not, see \<http://www.gnu.org/licenses/\>.