Resource List Server

Anca-Maria Vamanu

Voice Sistem SRL

Edited by

Anca-Maria Vamanu

Revision History
Revision $Revision: 8742 $$Date: 2012-02-22 18:34:34 +0100 (Wed, 22 Feb 2012) $

Table of Contents

1. Admin Guide
1.1. Overview
1.2. Dependencies
1.2.1. OpenSIPS Modules
1.2.2. External Libraries or Applications
1.3. Exported Parameters
1.3.1. db_url(str)
1.3.2. xcap_table(str)
1.3.3. rlsubs_table(str)
1.3.4. rlpres_table(str)
1.3.5. clean_period (int)
1.3.6. waitn_time (int)
1.3.7. max_expires (int)
1.3.8. hash_size (int)
1.3.9. xcap_root (str)
1.3.10. integrated_xcap_server (int)
1.3.11. to_presence_code (int)
1.3.12. rls_event (str)
1.3.13. presence_server (str)
1.3.14. server_address (str)
1.4. Exported Functions
1.4.1. rls_handle_subscribe()
1.4.2. rls_handle_notify()
1.5. Installation
2. Developer Guide

List of Examples

1.1. Set db_url parameter
1.2. Set xcap_table parameter
1.3. Set rlsubs_table parameter
1.4. Set rlpres_table parameter
1.5. Set clean_period parameter
1.6. Set waitn_time parameter
1.7. Set max_expires parameter
1.8. Set hash_size parameter
1.9. Set hash_size parameter
1.10. Set integrated_xcap_server parameter
1.11. Set to_presence_code parameter
1.12. Set rls_event parameter
1.13. Set presence_server parameter
1.14. Set server_address parameter
1.15. rls_handle_subscribe usage
1.16. rls_handle_notify usage

Chapter 1. Admin Guide

1.1. Overview

The modules is a Resource List Server implementation following the specification in RFC 4662 and RFC 4826.

The server is independent from local presence servers, retrieving presence information with Subscribe-Notify messages.

The module uses the presence module as a library, as it requires a resembling mechanism for handling Subscribe. Therefore, in case the local presence server is not collocated on the same machine with the RL server, the presence module should be loaded in a library mode only (see doc for presence module).

It handles subscription to lists in an event independent way.The default event is presence, but if some other events are to be handled by the server, they should be added using the module parameter "rls_events".

It works with XCAP server for storage. There is also the possibility to configure it to work in an integrated_xcap server mode, when it only queries database for the resource lists documents. This is useful in a small architecture when all the clients use an integrated server and there are no references to exterior documents in their lists.

The same as presence module, it has a caching mode with periodical update in database for subscribe information. The information retrieved with Notify messages is stored in database only.

1.2. Dependencies

1.2.1. OpenSIPS Modules

The following modules must be loaded before this module:

  • a database module.

  • signaling.

  • tm.

  • presence- in a library mode.

  • pua.

1.2.2. External Libraries or Applications

  • libxml-dev.

1.3. Exported Parameters

1.3.1. db_url(str)

The database url.

Default value is “mysql://opensips:opensipsrw@localhost/opensips”.

Example 1.1. Set db_url parameter

modparam("rls", "db_url", "dbdriver://username:password@dbhost/dbname")

1.3.2. xcap_table(str)

The name of the xcap table in which the integrated server or the xcap_client module writes. If integrated_xcap_server parameter not set, the name of the table must be the same as the one set for the xcap_client module.

Default value is “xcap”.

Example 1.2. Set xcap_table parameter

modparam("rls", "xcap_table", "xcaps");

1.3.3. rlsubs_table(str)

The name of the db table where resource lists subscription information is stored.

Default value is “rls_watchers”.

Example 1.3. Set rlsubs_table parameter

modparam("rls", "rlsubs_table", "rls_subscriptions")

1.3.4. rlpres_table(str)

The name of the db table where notified event specific information is stored.

Default value is “rls_presentity”.

Example 1.4. Set rlpres_table parameter

modparam("rls", "rlpres_table", "rls_notify")

1.3.5. clean_period (int)

The period at which to check for expired information.

Default value is “100”.

Example 1.5. Set clean_period parameter

modparam("rls", "clean_period", 100)

1.3.6. waitn_time (int)

The timer period at which the server should attempt to send Notifies with the updated presence state of the subscribed list or watcher information.

Default value is “50”.

Example 1.6. Set waitn_time parameter

modparam("rls", "waitn_time", 10)

1.3.7. max_expires (int)

The maximum accepted expires for a subscription to a list.

Default value is “7200”.

Example 1.7. Set max_expires parameter

modparam("rls", "max_expires", 10800)

1.3.8. hash_size (int)

The dimension of the hash table used to store subscription to a list. This parameter will be used as the power of 2 when computing table size.

Default value is “9 (512)”.

Example 1.8. Set hash_size parameter

modparam("rls", "hash_size", 11)

1.3.9. xcap_root (str)

The address of the xcap server.

Default value is “NULL”.

Example 1.9. Set hash_size parameter

modparam("rls", "xcap_root", "")

1.3.10. integrated_xcap_server (int)

This parameter should be set if only integrated xcap servers are used to store resource lists.

Default value is “0”.

Example 1.10. Set integrated_xcap_server parameter

modparam("rls", "integrated_xcap_server", 1)

1.3.11. to_presence_code (int)

The code to be returned by rls_handle_subscribe function if the processed Subscribe is not a resource list Subscribe. This code can be used in an architecture with presence and rls servers collocated on the same machine, to call handle_subscribe on the message causing this code.

Default value is “0”.

Example 1.11. Set to_presence_code parameter

modparam("rls", "to_presence_code", 10)

1.3.12. rls_event (str)

The default event that RLS handles is presence. If some other events should also be handled by RLS they should be added using this parameter. It can be set more than once.

Default value is “"presence"”.

Example 1.12. Set rls_event parameter

modparam("rls", "rls_event", "dialog;sla")

1.3.13. presence_server (str)

The address of the presence server. It will be used as outbound proxy for Subscribe requests sent by the RLS server to bouncing on and off the proxy and having to include special processing for this messages in the proxy's configuration file.

Example 1.13. Set presence_server parameter

modparam("rls", "presence_server", "")

1.3.14. server_address (str)

The address of the server that will be used as a contact in sent Subscribe requests and 200 OK replies for Subscribe messages for RLS. It is compulsory.

Example 1.14. Set server_address parameter

modparam("rls", "server_address", "")

1.4. Exported Functions

1.4.1.  rls_handle_subscribe()

This function detects if a Subscribe message should be handled by RLS. If not it replies with the configured to_presence_code. If it is, it extracts the dialog info and sends aggregate Notify requests with information for the list.

This function can be used from REQUEST_ROUTE.

Example 1.15. rls_handle_subscribe usage

For presence and rls on the same machine:
	modparam(rls, "to_presence_code", 10)

		$var(ret_code)= rls_handle_subscribe();

		if($var(ret_code)== 10)


For rls only:


1.4.2.  rls_handle_notify()

This function has to be called for Notify messages sent by presence servers in reply to the Subscribe messages sent by RLS.

This function can be used from REQUEST_ROUTE.

It can return 3 codes:

  • 1 - the Notify was inside a dialog that was recognized by the RLS server and was processed successfully.

  • 2 - the Notify did not belog to a dialog initiated by the RLS server.

  • -1 - an error occurred during processing.

Example 1.16. rls_handle_notify usage


1.5. Installation

The module requires 2 table in OpenSIPS database: rls_presentity and rls_watchers.The SQL syntax to create them can be found in rls-create.sql script in the database directories in the opensips/scripts folder. You can also find the complete database documentation on the project webpage,

Chapter 2. Developer Guide

The module provides no functions to be used in other OpenSIPS modules.