How to access a database from Yate's Javascript module

Using the example below you will learn how to:

• retrieve information from database
• route call to the result obtained from database

Configure script in Javascript module

To configure a routing script you have to list it in the javascript.conf file . If is a routing script then in section [general] the parameter in which the name of the script is written is routing. The path to the file is set in parameter scripts_dir. If you need to set other javascript files then use [scripts] section.

[general]
routing=example.js

Configure database account

You can set connection between Yate and MySQL database or Yate and PostGreSQL database module depending on your preference.

First you must check if module that you will use is loaded. If not, install devel packages.
The easiest way to check this, is from rmanager to write command status and to see if module name is listed there.

In MySQL the configuration file is mysqldb.conf and in PostgreSQL the configuration file is pgsqldb.conf.

Let's set account 'yateadmin' so we can use it in our examples, in mysqldb.conf:

[yateadmin]
database=yateadmin
user=mysql
password=yate

Then in MySQL:

• create database yateadmin
• create tables: lines and test.

Database Examples

Retrieve information from DB

// Get DB Object
var m = new Message("database");
// Specify connection to use
m.account = "yateadmin";
// Define Query
m.query = "SELECT * FROM lines WHERE location IS NOT NULL ORDER BY line LIMIT 5";
// Run the Query
if (m.dispatch()) {
    if (m.rows > 0) {
        Engine.output("Got " + m.rows + " records of " + m.columns + " fields");
        Engine.output("result[0,0] = " + m.getResult(0,0));
        var res = m.getColumn("location");
        for (var i = 0; i < res.length; i++) {
            Engine.output("location[" + i + "] = " + res[i]);
        }
    }
}
else {
    Engine.output("Query failed");
}

Example with call interaction

// Get DB Object, Account, Query
var m = new Message("database");
m.account = "yateadmin";
m.query = "SELECT test from test";

// Run the Query
if (m.dispatch())
{
	Engine.output("Query Ok");
	if (m.rows > 0) 
	{
		Engine.output("result[0,0] = " + m.getResult(0,0));

		// assuming m.getResult(0,0) returns "tone/busy" or "sip/sip:345@10.11.12.13"
		Channel.callJust(m.getResult(0,0));
	}
}

See also

• How to do routing using javascript