SQLOps Module

Daniel-Constantin Mierla

asipto.com

Edited by

Daniel-Constantin Mierla


Table of Contents

1. Admin Guide
1. Overview
2. Dependencies
2.1. Kamailio Modules
2.2. External Libraries or Applications
3. Exported Parameters
3.1. sqlcon (str)
4. Exported Functions
4.1. sql_query(connection, query, result)
4.2. sql_result_free(result)
5. Exported pseudo-variables
5.1. $dbr(result=>key)

List of Examples

1.1. Set sqlcon parameter
1.2. sql_query() usage
1.3. sql_result_free() usage
1.4. $dbr(result=>key) usage

Chapter 1. Admin Guide

1. Overview

The module adds support for raw SQL queries in configuration file.

Among features:

  • many DB connections - the module can connect to many databases on different servers using different DB driver modules at the same time.

  • many DB results - the module can store many results of different SQL queries in separate structures at the same time. Thus is possible to work in parallel with several DB results.

  • access via pseudo-variables - the content of SQL query result is accessible via pseudo-variables. Please note that only integer and string variables are supported at the moment because of the internal usage of “AVPs” to hold the values. So its not possible for example to return floating point or big integer values this way.

  • array indexes - fast access to result values via array possition: [row,column].

  • persistence in process space - a result can be used many times in same worker process. Query once, use many times.

2. Dependencies

2.1. Kamailio Modules

The following modules must be loaded before this module:

  • a DB SQL module (mysql, postgres, ...).

2.2. External Libraries or Applications

The following libraries or applications must be installed before running Kamailio with this module loaded:

  • None.

3. Exported Parameters

3.1. sqlcon (str)

The definition of DB connection. The value of the parameter must have the following format:

  • "connection_name=>database_url"

The parameter can be set multiple times to get many DB connections in same configuration file.

  • connection_name - string specifying the name of DB connection. This string is used by sql_query() function to refer to the DB connection.

  • database_url - URL to connect to database.

Default value is NULL.

Example 1.1. Set sqlcon parameter

...
modparam("sqlops","sqlcon","cb=>mysql://openser:abc@10.10.1.1/testdb")
modparam("sqlops","sqlcon","ca=>mysql://openser:abc@localhost/openser")
...

4. Exported Functions

4.1.  sql_query(connection, query, result)

Make a SQL query using 'connection' and store data in 'result'.

  • connection - the name of the connection to be used for query (defined via sqlcon parameter).

  • query - SQL query string, can contain pseudo-variables.

  • result - string name to identify the result. Will be used by $dbr(...) pseudo-variable to access result attributes.

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE, ONREPLY_ROUTE, BRANCH_ROUTE.

Example 1.2. sql_query() usage

...
modparam("sqlops","sqlcon","ca=>mysql://openser:abc@localhost/openser")
...
sql_query("ca", "select * from domain", "ra");
xlog("number of rows in table domain: $dbr(ra=>rows)\n");
sql_result_free("ra");
...

4.2.  sql_result_free(result)

Free data in SQL 'result'.

This function can be used from REQUEST_ROUTE, FAILURE_ROUTE, ONREPLY_ROUTE, BRANCH_ROUTE.

Example 1.3. sql_result_free() usage

...
modparam("sqlops","sqlcon","ca=>mysql://openser:abc@localhost/openser")
...
sql_query("ca", "select * from domain", "ra");
xlog("number of rows in table domain: $dbr(ra=>rows)\n");
...
sql_result_free("ra");
...

5. Exported pseudo-variables

5.1. $dbr(result=>key)

Access hash table entries.

The “result” must be the name identifying a SQL result (third parameter of sql_query(...)).

The “key” can be:

  • rows - return number of rows in result

  • cols - return the number of columns in result.

  • [row,col] - return the value at position (row,col) in result. 'row' and 'col' must be integer or pseudo-variable holding an integer.

  • colname[N] - return the name of the N-th column in result.

Example 1.4. $dbr(result=>key) usage

...
modparam("sqlops","sqlcon","ca=>mysql://openser:abc@localhost/openser")
...
sql_query("ca", "select * from domain", "ra");
xlog("rows: $dbr(ra=>rows) cols: $dbr(ra=>cols)\n");
if($dbr(ra=>rows)>0)
{
    $var(i) = 0;
    while($var(i)<$dbr(ra=>cols))
    {
        xlog("--- SCRIPT: column[$var(i)] = $dbr(ra=>colname[$var(i)])\n");
        $var(i) = $var(i) + 1;
    }
    $var(i) = 0;
    while($var(i)<$dbr(ra=>rows))
    {
        $var(j) = 0;
        while($var(j)<$dbr(ra=>cols))
        {
            xlog("[$var(i),$var(j)] = $dbr(ra=>[$var(i),$var(j)])\n");
            $var(j) = $var(j) + 1;
        }
        $var(i) = $var(i) + 1;
    }
}
sql_result_free("ra");
...