cachedb_sql Module

Vladut-Stefan Paiu

   OpenSIPS Solutions

Edited by

Vladut-Stefan Paiu

   Copyright © 2013 www.opensips-solutions.com
     __________________________________________________________

   Table of Contents

   1. Admin Guide

        1.1. Overview
        1.2. Advantages
        1.3. Limitations
        1.4. Dependencies

              1.4.1. OpenSIPS Modules
              1.4.2. External Libraries or Applications

        1.5. Exported Parameters

              1.5.1. cachedb_url (string)
              1.5.2. db_table (string)
              1.5.3. key_column (string)
              1.5.4. value_column (string)
              1.5.5. counter_column (string)
              1.5.6. expires_column (string)
              1.5.7. cache_clean_period (int)
              1.5.8. Exported Functions

   2. Frequently Asked Questions

   List of Examples

   1.1. Set db_url parameter
   1.2. Usage example
   1.3. Set db_url parameter
   1.4. Set key_column parameter
   1.5. Set value_column parameter
   1.6. Set counter_column parameter
   1.7. Set expires_column parameter
   1.8. Set cache_clean_period parameter

Chapter 1. Admin Guide

1.1. Overview

   This module is an implementation of a cache system designed to
   work with a regular SQL-based server. It uses the internal DB
   interface to connect to the back-end, and also implements the
   Key-Value interface exported from the core.

1.2. Advantages

     * memory costs are no longer on the server
     * the cache is 100% persistent. A restart of OpenSIPS server
       will not affect the DB. The DB is also persistent so it can
       also be restarted without loss of information.
     * Multiple OpenSIPS instances can easily share key-value
       information via a regular SQL-based database

1.3. Limitations

     * The module's counter operations ( ADD and SUB ) are
       currently only supported by MySQL

1.4. Dependencies

1.4.1. OpenSIPS Modules

   None.

1.4.2. External Libraries or Applications

   The following libraries or applications must be installed
   before running OpenSIPS with this module loaded:
     * none:

1.5. Exported Parameters

1.5.1. cachedb_url (string)

   The url of the Database that OpenSIPS will connect to in order
   to use the from script cache_store,cache_fetch, etc operations.

   The format to follow is : sql:[conn_id]-dburl

   The parameter can be set multiple times to create multiple
   connections accessible from the OpenSIPS script.

   Example 1.1. Set db_url parameter
...
modparam("cachedb_sql", "cachedb_url", "sql:1st-mysql://root:vlad@localh
ost/opensips_sql")
...

   Example 1.2. Usage example
...
modparam("cachedb_sql", "cachedb_url", "sql:1st-mysql://root:vlad@localh
ost/opensips_sql")
modparam("cachedb_sql", "cachedb_url", "sql:2nd-postgres://root:vlad@loc
alhost/opensips_pg")
...
...
cache_store("sql:1st-mysql","key","$ru value");
cache_store("sql:2nd-postgres","counter","10");
...

1.5.2. db_table (string)

   The table of the Database that OpenSIPS will connect to in
   order to use the from script cache_store,cache_fetch, etc
   operations.

   Example 1.3. Set db_url parameter
...
modparam("cachedb_sql", "db_table","my_table");
...

1.5.3. key_column (string)

   The column where the key will be stored

   Example 1.4. Set key_column parameter
...
modparam("cachedb_sql", "key_column","some_name");
...

1.5.4. value_column (string)

   The column where the value will be stored

   Example 1.5. Set value_column parameter
...
modparam("cachedb_sql", "value_column","some_name");
...

1.5.5. counter_column (string)

   The column where the counter value will be stored

   Example 1.6. Set counter_column parameter
...
modparam("cachedb_sql", "counter_column","some_name");
...

1.5.6. expires_column (string)

   The column where the expires will be stored

   Example 1.7. Set expires_column parameter
...
modparam("cachedb_sql", "expires_column","some_name");
...

1.5.7. cache_clean_period (int)

   The interval in seconds at which the expired keys will be
   removed from the database. Default value is 60 ( seconds )

   Example 1.8. Set cache_clean_period parameter
...
modparam("cachedb_sql", "cache_clean_period",10);
...

1.5.8. Exported Functions

   The module does not export functions to be used in
   configuration script.

Chapter 2. Frequently Asked Questions

   2.1.

       What happened with the old “db_url” module parameter?

       It was replaced with the “cachedb_url” parameter. See the
       documentation for the usage of the “cachedb_url” parameter.
