The map Statement

Syntax

map <module-name> "string" {
	<server-attribute> <op> <field>
}

The map section is one of the most useful new additions to version 4. It allows for the mapping of arbitrary information from a database to attributes inside of the server.

The map syntax is similar for all use-cases. It consists of:

<module-name>: The name of the module which implements this particular map
"string": A module-specific query string. This string is usually a database query which returns one or more fields.
<server-attribute>: The server attribute which is assigned the value taken from the database query.
<op>: The operator such as =, :=, etc. Any editing operator defined for an update statement is permissible.
<field>: The name of the field from the database. For SQL, the field names are usually column names. For LDAP, the field names are usually LDAP attributes.

The <field> value should generally be enclosed in single quotes which prevents any additional expansion of the value. When the right hand side is instead a double-quoted string, that string is expanded dynamically. The resulting value is then taken as the field name.

If the map fails for any reason, then all of the results are discarded, and the map does not affect any server attributes. For example, the database query can return no results, or a dynamically expanded <field> can refer to a non-existent field name. In both cases, the map statement returns fail, and no server attributes are affected.

Examples

map sql "SELECT column1, column2, column3 from table WHERE user=%{User-Name}" {
    &reply.Framed-IP-Address := 'column1'
    &reply.Filter-Id := 'column2'
    &reply.Reply-Message := 'column3'
}