# Handling server webservice calls

In modern applications, web application may need to request some other web applications on behalf of the authenticated users. There are three ways to do this:

- the Ugly : provide to all applications SSO cookie. Not secured because SSO cookie can be caught and used everywhere, every time by everyone!!! NOT RECOMMENDED.

- the Bad (Secure Token Handler) : Deprecated. Can be used in specific cases

- the Good (Service Token Handler): See below ! (Thanks Sergio…)

The “Bad” method consists to give the token (cookie value) to WebApp1 which uses it as cookie header in its request. Since 2.0 version, LL::NG gives a better way (the Good !) to do this by using limited scope tokens.

Tokens are time limited (30 seconds by default) and URL restricted.

## Webapp1 handler configuration

Select Main handler type to protect WebApp1 and insert a header named X-Llng-Token filled with this value:

    token( $_session_id, 'webapp2.example.com', 'webapp3.example.com', 'serviceHeader1=webapp1.example.com', "testHeader=$uid" )

WebApp1 can read this header and use it in its requests by setting the `X-Llng-Token` header. The token is built by using the session ID and authorized virtualhosts list. By default, the Service Token is only available during 30 seconds and for specified virtualhosts. The token can be use to send service headers to webapp2 like origin host by example.

You can set ServiceToken TTL in the virtualHost options in Manager for each required virtualHost.

You can also set ServiceToken default timeout (30 seconds) by editing `lemonldap-ng.ini` in section [handler]:

    [handler]
    handlerServiceTokenTTL = 30

Note

Service token timeout can be set for each virtual hosts.

## Webapp2 handler configuration

Change handler type to ServiceToken. So it is able to manage both user and server connections. And that’s all !