Authenticators

Module: jupyterhub.auth

Base Authenticator class and the default PAM Authenticator

class jupyterhub.auth.Authenticator(**kwargs)

Base class for implementing an authentication provider for JupyterHub

add_user(user)

Hook called when a user is added to JupyterHub

This is called:
  • When a user first authenticates
  • When the hub restarts, for all users.

This method may be a coroutine.

By default, this just adds the user to the whitelist.

Subclasses may do more extensive things, such as adding actual unix users, but they should call super to ensure the whitelist is updated.

Note that this should be idempotent, since it is called whenever the hub restarts for all users.

Parameters:user (User) – The User wrapper object
authenticate(handler, data)

Authenticate a user with login form data

This must be a tornado gen.coroutine. It must return the username on successful authentication, and return None on failed authentication.

Checking the whitelist is handled separately by the caller.

Parameters:
  • handler (tornado.web.RequestHandler) – the current request handler
  • data (dict) – The formdata of the login form. The default form has ‘username’ and ‘password’ fields.
Returns:

The username of the authenticated user, or None if Authentication failed

Return type:

username (str or None)

check_whitelist(username)

Check if a username is allowed to authenticate based on whitelist configuration

Return True if username is allowed, False otherwise. No whitelist means any username is allowed.

Names are normalized before being checked against the whitelist.

delete_user(user)

Hook called when a user is deleted

Removes the user from the whitelist. Subclasses should call super to ensure the whitelist is updated.

Parameters:user (User) – The User wrapper object
get_authenticated_user(handler, data)

Authenticate the user who is attempting to log in

Returns normalized username if successful, None otherwise.

This calls authenticate, which should be overridden in subclasses, normalizes the username if any normalization should be done, and then validates the name in the whitelist.

This is the outer API for authenticating a user. Subclasses should not need to override this method.

The various stages can be overridden separately:
  • authenticate turns formdata into a username
  • normalize_username normalizes the username
  • check_whitelist checks against the user whitelist
get_handlers(app)

Return any custom handlers the authenticator needs to register

Used in conjugation with login_url and logout_url.

Parameters:app (JupyterHub Application) – the application object, in case it needs to be accessed for info.
Returns:list of ('/url', Handler) tuples passed to tornado. The Hub prefix is added to any URLs.
Return type:handlers (list)
login_url(base_url)

Override this when registering a custom login handler

Generally used by authenticators that do not use simple form based authentication.

The subclass overriding this is responsible for making sure there is a handler available to handle the URL returned from this method, using the get_handlers method.

Parameters:base_url (str) – the base URL of the Hub (e.g. /hub/)
Returns:The login URL, e.g. ‘/hub/login’
Return type:str
logout_url(base_url)

Override when registering a custom logout handler

The subclass overriding this is responsible for making sure there is a handler available to handle the URL returned from this method, using the get_handlers method.

Parameters:base_url (str) – the base URL of the Hub (e.g. /hub/)
Returns:The logout URL, e.g. ‘/hub/logout’
Return type:str
normalize_username(username)

Normalize the given username and return it

Override in subclasses if usernames need different normalization rules.

The default attempts to lowercase the username and apply username_map if it is set.

post_spawn_stop(user, spawner)

Hook called after stopping a user container

Can be used to do auth-related cleanup, e.g. closing PAM sessions.

pre_spawn_start(user, spawner)

Hook called before spawning a user’s server

Can be used to do auth-related startup, e.g. opening PAM sessions.

validate_username(username)

Validate a normalized username

Return True if username is valid, False otherwise.

class jupyterhub.auth.LocalAuthenticator(**kwargs)

Base class for Authenticators that work with local Linux/UNIX users

Checks for local users, and can attempt to create them if they exist.

add_system_user(user)

Create a new local UNIX user on the system.

Tested to work on FreeBSD and Linux, at least.

add_user(user)

Hook called whenever a new user is added

If self.create_system_users, the user will attempt to be created if it doesn’t exist.

check_group_whitelist(username)

If group_whitelist is configured, check if authenticating user is part of group.

static system_user_exists(user)

Check if the user exists on the system

class jupyterhub.auth.PAMAuthenticator(**kwargs)

Authenticate local UNIX users with PAM