1. prefix_route Module

Alfred E. Heggestad

Telio Telecom

1.1. Overview

1.2. Parameters

1.2.1. db_url (string)
1.2.2. db_table (string)

1.3. Functions

1.3.1. prefix_route()

1.4. RPC Commands

1.4.1. prefix_route.reload
1.4.2. prefix_route.dump

1.5. Database Structure

1.1. Overview

The prefix_route module does routing based on a set of prefixes from the database. The prefix rule-set is loaded from the database into a binary tree in memory, either on startup or when issuing the "prefix_route.reload" RPC command. When calling the "prefix_route()" function from the ser.cfg configuration script, it will try to match the user part of the request URI with the best matching route. If a route is found, it will be used for further processing. If not found normal processing will continue.

Development was sponsored by Telio Telecom.

1.2. Parameters

1.2.1. `db_url` (string)

This is URL of the database to be used.

Default value is "mysql://ser@localhost/ser"

Example 1. Setting db_url parameter

...
modparam("prefix_route", "db_url", "mysql://ser:pass@db_host/ser")
...

1.2.2. `db_table` (string)

The name of table where to read prefix route set.

Default value is "prefix_route".

Example 2. Setting db_table parameter

...
modparam("prefix_route", "db_table", "new_prefix_route")
...

1.3. Functions

1.3.1. `prefix_route()`

This function tries to find a route from the user part of the request URI. If a route is found, it will be used for further processing. Otherwise the function will return false.

Example 3. prefix_route() usage

...
  if (!prefix_route()) {
      xlog("L_ERR", "prefix_route(): no matching routes\n");
  }
...

1.4. RPC Commands

1.4.1. `prefix_route.reload`

Reload prefix route tree from the database. Validation is done and the prefix route tree will only be reloaded if there are no errors.

1.4.2. `prefix_route.dump`

Dump the current prefix route tree.

1.5. Database Structure

A prefix route set consists of three fields:

prefix - varchar(64) - Prefix rule
route - varchar(64) - Route name
comment - varchar(64) - Free-form comment

Example 4. Sample data

...
   +--------+-------+---------------+
   | prefix | route | comment       |
   +--------+-------+---------------+
   | 46     | SE    | Sweden        | 
   | 47     | NO    | Norway        | 
   | 479    | NOMOB | Norway mobile | 
   | 49     | DE    | Deutschland   | 
   | 39     | IT    | Italy         | 
   +--------+-------+---------------+
...