# Application configuration¶

## Module: jupyterhub.app¶

The multi-user notebook application

### JupyterHub¶

class jupyterhub.app.JupyterHub(**kwargs)

An Application for starting a Multi-User Jupyter Notebook server.

config c.JupyterHub.active_server_limit = Int(0)

Maximum number of concurrent servers that can be active at a time.

Setting this can limit the total resources your users can consume.

An active server is any server that’s not fully stopped. It is considered active from the time it has been requested until the time that it has completely stopped.

If this many user servers are active, users will not be able to launch new servers until a server is shutdown. Spawn requests will be rejected with a 429 error asking them to try again.

If set to 0, no limit is enforced.

config c.JupyterHub.active_user_window = Int(1800)

Duration (in seconds) to determine the number of active users.

config c.JupyterHub.admin_access = Bool(False)

Grant admin users permission to access single-user servers.

Users should be properly informed if this is enabled.

config c.JupyterHub.admin_users = Set()

config c.JupyterHub.allow_named_servers = Bool(False)

Allow named single-user servers per user

config c.JupyterHub.answer_yes = Bool(False)

Answer yes to any questions (e.g. confirm overwrite)

config c.JupyterHub.api_tokens = Dict()

PENDING DEPRECATION: consider using service_tokens

Allows ahead-of-time generation of API tokens for use by externally managed services, which authenticate as JupyterHub users.

Consider using service_tokens for general services that talk to the JupyterHub API.

config c.JupyterHub.authenticator_class = Type(<class 'jupyterhub.auth.PAMAuthenticator'>)

Class for authenticating users.

This should be a class with the following form:

• constructor takes one kwarg: config, the IPython config object.

with an authenticate method that:

• is a coroutine (asyncio or tornado)
• returns username on success, None on failure
• takes two arguments: (handler, data), where handler is the calling web.RequestHandler, and data is the POST form data from the login page.
config c.JupyterHub.base_url = URLPrefix('/')

The base URL of the entire application.

Add this to the beginning of all JupyterHub URLs. Use base_url to run JupyterHub within an existing website.

config c.JupyterHub.bind_url = Unicode('http://:8000')

The public facing URL of the whole JupyterHub application.

This is the address on which the proxy will bind. Sets protocol, ip, base_url

config c.JupyterHub.cleanup_proxy = Bool(True)

Whether to shutdown the proxy when the Hub shuts down.

Disable if you want to be able to teardown the Hub while leaving the proxy running.

Only valid if the proxy was starting by the Hub process.

If both this and cleanup_servers are False, sending SIGINT to the Hub will only shutdown the Hub, leaving everything else running.

The Hub should be able to resume from database state.

config c.JupyterHub.cleanup_servers = Bool(True)

Whether to shutdown single-user servers when the Hub shuts down.

Disable if you want to be able to teardown the Hub while leaving the single-user servers running.

If both this and cleanup_proxy are False, sending SIGINT to the Hub will only shutdown the Hub, leaving everything else running.

The Hub should be able to resume from database state.

config c.JupyterHub.concurrent_spawn_limit = Int(100)

Maximum number of concurrent users that can be spawning at a time.

Spawning lots of servers at the same time can cause performance problems for the Hub or the underlying spawning system. Set this limit to prevent bursts of logins from attempting to spawn too many servers at the same time.

This does not limit the number of total running servers. See active_server_limit for that.

If more than this many users attempt to spawn at a time, their requests will be rejected with a 429 error asking them to try again. Users will have to wait for some of the spawning services to finish starting before they can start their own.

If set to 0, no limit is enforced.

config c.JupyterHub.config_file = Unicode('jupyterhub_config.py')

config c.JupyterHub.confirm_no_ssl = Bool(False)

DEPRECATED: does nothing

config c.JupyterHub.cookie_max_age_days = Float(14)

Number of days for a login cookie to be valid. Default is two weeks.

config c.JupyterHub.cookie_secret = Bytes(b'')

Should be exactly 256 bits (32 bytes).

config c.JupyterHub.cookie_secret_file = Unicode('jupyterhub_cookie_secret')

File in which to store the cookie secret.

config c.JupyterHub.data_files_path = Unicode('')

The location of jupyterhub data files (e.g. /usr/local/share/jupyterhub)

config c.JupyterHub.db_kwargs = Dict()

Include any kwargs to pass to the database connection. See sqlalchemy.create_engine for details.

config c.JupyterHub.db_url = Unicode('sqlite:///jupyterhub.sqlite')

url for the database. e.g. sqlite:///jupyterhub.sqlite

config c.JupyterHub.debug_db = Bool(False)

log all database transactions. This has A LOT of output

config c.JupyterHub.debug_proxy = Bool(False)

DEPRECATED since version 0.8: Use ConfigurableHTTPProxy.debug

config c.JupyterHub.default_url = Unicode('')

The default URL for users when they arrive (e.g. when user directs to “/”)

By default, redirects users to their own server.

config c.JupyterHub.extra_handlers = List()

Register extra tornado Handlers for jupyterhub.

Should be of the form ("<regex>", Handler)

The Hub prefix will be added, so /my-page will be served at /hub/my-page.

config c.JupyterHub.extra_log_file = Unicode('')

DEPRECATED: use output redirection instead, e.g.

jupyterhub &>> /var/log/jupyterhub.log

config c.JupyterHub.extra_log_handlers = List()

Extra log handlers to set on JupyterHub logger

config c.JupyterHub.generate_config = Bool(False)

Generate default config file

config c.JupyterHub.hub_bind_url = Unicode('')

The URL on which the Hub will listen. This is a private URL for internal communication. Typically set in combination with hub_connect_url. If a unix socket, hub_connect_url must also be set.

For example:

http://127.0.0.1:8081” “unix+http://%2Fsrv%2Fjupyterhub%2Fjupyterhub.sock”

New in version 0.9.

config c.JupyterHub.hub_connect_ip = Unicode('')

The ip or hostname for proxies and spawners to use for connecting to the Hub.

Use when the bind address (hub_ip) is 0.0.0.0 or otherwise different from the connect address.

Default: when hub_ip is 0.0.0.0, use socket.gethostname(), otherwise use hub_ip.

Note: Some spawners or proxy implementations might not support hostnames. Check your spawner or proxy documentation to see if they have extra requirements.

New in version 0.8.

config c.JupyterHub.hub_connect_port = Int(0)

DEPRECATED

Use hub_connect_url

New in version 0.8.

Deprecated since version 0.9: Use hub_connect_url

config c.JupyterHub.hub_connect_url = Unicode('')

The URL for connecting to the Hub. Spawners, services, and the proxy will use this URL to talk to the Hub.

Only needs to be specified if the default hub URL is not connectable (e.g. using a unix+http:// bind url).

JupyterHub.hub_connect_ip JupyterHub.hub_bind_url

New in version 0.9.

config c.JupyterHub.hub_ip = Unicode('127.0.0.1')

The ip address for the Hub process to bind to.

By default, the hub listens on localhost only. This address must be accessible from the proxy and user servers. You may need to set this to a public ip or ‘’ for all interfaces if the proxy or user servers are in containers or on a different host.

See hub_connect_ip for cases where the bind and connect address should differ, or hub_bind_url for setting the full bind URL.

config c.JupyterHub.hub_port = Int(8081)

The internal port for the Hub process.

This is the internal port of the hub itself. It should never be accessed directly. See JupyterHub.port for the public port to use when accessing jupyterhub. It is rare that this port should be set except in cases of port conflict.

See also hub_ip for the ip and hub_bind_url for setting the full bind URL.

config c.JupyterHub.ip = Unicode('')

The public facing ip of the whole JupyterHub application (specifically referred to as the proxy).

This is the address on which the proxy will listen. The default is to listen on all interfaces. This is the only address through which JupyterHub should be accessed by users.

config c.JupyterHub.jinja_environment_options = Dict()

Supply extra arguments that will be passed to Jinja environment.

config c.JupyterHub.last_activity_interval = Int(300)

Interval (in seconds) at which to update last-activity timestamps.

config c.JupyterHub.load_groups = Dict()

This strictly adds groups and users to groups.

Loading one set of groups, then starting JupyterHub again with a different set will not remove users or groups from previous launches. That must be done through the API.

config c.JupyterHub.log_datefmt = Unicode('%Y-%m-%d %H:%M:%S')

The date format used by logging formatters for %(asctime)s

config c.JupyterHub.log_format = Unicode('[%(name)s]%(highlevel)s %(message)s')

The Logging format template

config c.JupyterHub.log_level = Enum(30)

Set the log level by value or name.

config c.JupyterHub.logo_file = Unicode('')

Specify path to a logo image to override the Jupyter logo in the banner.

config c.JupyterHub.pid_file = Unicode('')

File to write PID Useful for daemonizing JupyterHub.

config c.JupyterHub.port = Int(8000)

The public facing port of the proxy.

This is the port on which the proxy will listen. This is the only port through which JupyterHub should be accessed by users.

config c.JupyterHub.proxy_api_ip = Unicode('')

DEPRECATED since version 0.8 : Use ConfigurableHTTPProxy.api_url

config c.JupyterHub.proxy_api_port = Int(0)

DEPRECATED since version 0.8 : Use ConfigurableHTTPProxy.api_url

config c.JupyterHub.proxy_auth_token = Unicode('')

DEPRECATED since version 0.8: Use ConfigurableHTTPProxy.auth_token

config c.JupyterHub.proxy_check_interval = Int(30)

Interval (in seconds) at which to check if the proxy is running.

config c.JupyterHub.proxy_class = Type(<class 'jupyterhub.proxy.ConfigurableHTTPProxy'>)

Select the Proxy API implementation.

config c.JupyterHub.proxy_cmd = Command()

DEPRECATED since version 0.8. Use ConfigurableHTTPProxy.command

config c.JupyterHub.redirect_to_server = Bool(True)

Redirect user to server (if running), instead of control panel.

config c.JupyterHub.reset_db = Bool(False)

Purge and reset the database.

config c.JupyterHub.service_check_interval = Int(60)

Interval (in seconds) at which to check connectivity of services with web endpoints.

config c.JupyterHub.service_tokens = Dict()

Dict of token:servicename to be loaded into the database.

Allows ahead-of-time generation of API tokens for use by externally managed services.

config c.JupyterHub.services = List()

List of service specification dictionaries.

A service

For instance:

services = [
{
'name': 'cull_idle',
'command': ['/path/to/cull_idle_servers.py'],
},
{
'url': 'http://127.0.0.1:1234',
'api_token': 'super-secret',
'environment':
}
]

config c.JupyterHub.spawner_class = Type(<class 'jupyterhub.spawner.LocalProcessSpawner'>)

The class to use for spawning single-user servers.

Should be a subclass of Spawner.

config c.JupyterHub.ssl_cert = Unicode('')

Path to SSL certificate file for the public facing interface of the proxy

When setting this, you should also set ssl_key

config c.JupyterHub.ssl_key = Unicode('')

Path to SSL key file for the public facing interface of the proxy

When setting this, you should also set ssl_cert

config c.JupyterHub.statsd_host = Unicode('')

Host to send statsd metrics to. An empty string (the default) disables sending metrics.

config c.JupyterHub.statsd_port = Int(8125)

Port on which to send statsd metrics about the hub

config c.JupyterHub.statsd_prefix = Unicode('jupyterhub')

Prefix to use for all metrics sent by jupyterhub to statsd

config c.JupyterHub.subdomain_host = Unicode('')

Run single-user servers on subdomains of this host.

This should be the full https://hub.domain.tld[:port].

Provides additional cross-site protections for javascript served by single-user servers.

Requires <username>.hub.domain.tld to resolve to the same host as hub.domain.tld.

In general, this is most easily achieved with wildcard DNS.

When using SSL (i.e. always) this also requires a wildcard SSL certificate.

config c.JupyterHub.template_paths = List()

Paths to search for jinja templates, before using the default templates.

config c.JupyterHub.template_vars = Dict()

Extra variables to be passed into jinja templates

config c.JupyterHub.tornado_settings = Dict()

Extra settings overrides to pass to the tornado application.

config c.JupyterHub.trust_user_provided_tokens = Bool(False)

Trust user-provided tokens (via JupyterHub.service_tokens) to have good entropy.

If you are not inserting additional tokens via configuration file, this flag has no effect.

In JupyterHub 0.8, internally generated tokens do not pass through additional hashing because the hashing is costly and does not increase the entropy of already-good UUIDs.

User-provided tokens, on the other hand, are not trusted to have good entropy by default, and are passed through many rounds of hashing to stretch the entropy of the key (i.e. user-provided tokens are treated as passwords instead of random keys). These keys are more costly to check.

If your inserted tokens are generated by a good-quality mechanism, e.g. openssl rand -hex 32, then you can set this flag to True to reduce the cost of checking authentication tokens.

config c.JupyterHub.upgrade_db = Bool(False)

Upgrade the database automatically on start.

Only safe if database is regularly backed up. Only SQLite databases will be backed up to a local file automatically.