How to invoke a JSF backing bean method from a non-faces request ?

Question

We have a requirement to replace our current login, for a web-application written in JSF using single sign-on. Currently our login.jsp invokes the authenticate method on a backing bean to achieve this and perform additional role validations. Now authentication will be done by my single sign-on server, but how do i invoke the authenticate method on the backing bean to perform the role validations

Answer 1

Set request parameters as managed properties and use the @PostConstruct annotation to execute some code immediately after bean construction and managed property setting.

You can set GET or POST request parameters as managed properties as follows:

<managed-bean>
    <managed-bean-name>bean</managed-bean-name>
    <managed-bean-class>mypackage.Bean</managed-bean-class>
    <managed-bean-scope>request</managed-bean-scope>
    <managed-property>
        <property-name>name1</property-name>
        <value>#{param.name1}</value>
    </managed-property>
    <managed-property>
        <property-name>name2</property-name>
        <value>#{param.name2}</value>
    </managed-property>
</managed-bean>

Or if you're already on JSF 2.0, then you can just use @ManagedProperty:

@ManagedProperty(value="#{param.name1}")
private String name1;

@ManagedProperty(value="#{param.name2}")
private String name2;

Those parameters will be set when the enduser fires a GET or POST request with a name1=value1&name2=value2 query string. The #{param.name1} EL expression basically stands for the result of request.getParameter("name1").

Now create a @PostConstruct method like follows:

@PostConstruct
public void init() {
    if (name1 != null && name2 != null) {
        // Both request parameters are been set. Do your thing here!
    }
}