# Check user plugin

This plugin allows us to check session attributes, access rights and transmitted headers for a specific user and URL. This can be useful for IT Ops, dev teams or administrators to debug or check rules. Plugin DISABLED by default.

## Configuration

Just enable it in the manager (section “plugins”).

- Parameters:
  - Activation: Enable / Disable this plugin
  - Identities use rule: Rule to define which profiles can be displayed (by example: `!$anonymous`)
  - Hidden attributes: Attributes not displayed
  - Attributes used for searching sessions: User's attributes used for searching sessions in backend if `whatToTrace` fails. Useful to look for sessions by mail or givenName. Let it blank to search by `whatToTrace` only.
  - Display empty headers: Rule to display ALL headers appended by LemonLDAP::NG including empty ones
  - Display empty value: Rule to display ALL attributes even empty ones
  - Display persistent session: Rule to display persistent session attributes

By examples :

* Search attributes => `mail uid givenName`

If `whatToTrace` fails, sessions are searched by `mail`, next `uid` if none session is found and so on...

* Display empty headers rule => `$uid eq "dwho"` -> Only 'dwho' will see empty headers

Keep in mind that Nginx HTTP proxy module gets rid of empty headers. If the value of a header field is an empty string then this field will not be passed to a proxied server. To avoid misunderstanding, it might be useful to not display empty headers.
Be careful to not display secret attributes.

checkUser plugin hidden attributes are concatenation of `checkUserHiddenAttributes` and `hiddenAttributes`. You just have to append checkUser specific attributes.

This plugin displays ALL user session attributes except the hidden ones.

You have to restrict access to specific users (administrators, DevOps, power users and so on...) by setting an access rule like other VirtualHosts.

By example: `$groups =~ /\bsu\b/`

To modify persistent sessions attributes ('_loginHistory _2fDevices notification_' by default), edit `lemonldap-ng.ini` in [portal] section:

    [portal]
    persistentSessionAttributes = _loginHistory _2fDevices notification_

## Usage

When enabled, `/checkuser` URL path is handled by this plugin.

With federated authentication, checkUser plugin works only if a session can be found in backend.