(topic-customizing-installer)=

# Customizing the Installer

The installer can be customized with commandline parameters. The default installer
is executed as:

```bash
curl -L https://tljh.jupyter.org/bootstrap.py \
 | sudo python3 - \
   <parameters>
```

This page documents the various options you can pass as commandline parameters to the installer.

(topic-customizing-installer-admin)=

## Serving a temporary "TLJH is building" page

`--show-progress-page` serves a temporary "TLJH is building" progress page while TLJH is building.

```{image} ../images/tljh-is-building-page.gif
:alt: Temporary progress page while TLJH is building
```

- The page will be accessible at `http://<tljh-public-ip>/index.html` in your browser.
  When TLJH installation is complete, the progress page page will stop and you will be able
  to access TLJH as usually at `http://<tljh-public-ip>`.
- From the progress page, you will also be able to access the installation logs, by clicking the
  **Logs** button or by going directly to `http://<tljh-public-ip>/logs` in your browser.
  To update the logs, refresh the page.

:::{note}
The `http://<tljh-public-ip>/index.html` page refreshes itself automatically every 30s.
When JupyterHub starts, a JupyterHub 404 HTTP error message (_Jupyter has lots of moons, but this is not one..._)
will be shown instead of the progress page. This means JupyterHub was started succesfully and you can access it
either by clicking the `Control Panel` button or by going to `http://<tljh-public-ip>/` directly.
:::

For example, to enable the progress page and add the first _admin_ user, you would run:

```bash
curl -L https://tljh.jupyter.org/bootstrap.py \
| sudo python3 - \
 --admin admin --show-progress-page
```

## Adding admin users

`--admin <username>:<password>` adds user `<username>` to JupyterHub as an admin user
and sets its password to be `<password>`.
Although it is not recommended, it is possible to only set the admin username at this point
and set the admin password after the installation.

Also, the `--admin` flag can be repeated multiple times. For example, to add `admin-user1`
and `admin-user2` as admins when installing, depending if you would like to set their passwords
during install you would:

- set `admin-user1` with password `password-user1` and `admin-user2` with `password-user2` using:

```bash
curl -L https://tljh.jupyter.org/bootstrap.py \
 | sudo python3 - \
   --admin admin-user1:password-user1 --admin admin-user2:password-user2
```

- set `admin-user1` and `admin-user2` to be admins, without any passwords at this stage, using:

```bash
curl -L https://tljh.jupyter.org/bootstrap.py \
 | sudo python3 - \
   --admin admin-user1 --admin admin-user2
```

- set `admin-user1` with password `password-user1` and `admin-user2` with no password at this stage using:

```bash
curl -L https://tljh.jupyter.org/bootstrap.py \
 | sudo python3 - \
   --admin admin-user1:password-user1 --admin admin-user2
```

## Installing python packages in the user environment

`--user-requirements-txt-url <url-to-requirements.txt>` installs packages specified
in the `requirements.txt` located at the given URL into the user environment at install
time. This is very useful when you want to set up a hub with a particular user environment
in one go.

For example, to install the latest requirements to run UC Berkeley's data8 course
in your new hub, you would run:

```bash
curl -L https://tljh.jupyter.org/bootstrap.py \
 | sudo python3 - \
   --user-requirements-txt-url https://raw.githubusercontent.com/data-8/materials-sp18/HEAD/requirements.txt
```

The URL **must** point to a working requirements.txt. If there are any errors, the installation
will fail.

:::{note}
When pointing to a file on GitHub, make sure to use the 'Raw' version. It should point to
`raw.githubusercontent.com`, not `github.com`.
:::

## Installing TLJH plugins

The Littlest JupyterHub can install additional _plugins_ that provide additional
features. They are most commonly used to install a particular _stack_ - such as
the [PANGEO Stack](https://github.com/yuvipanda/tljh-pangeo) for earth sciences
research, a stack for a particular class, etc. You can find more information about
writing plugins and a list of existing plugins at [](/contributing/plugins).

`--plugin <plugin-to-install>` installs and activates a plugin. You can pass it
however many times you want. Since plugins are distributed as python packages,
`<plugin-to-install>` can be anything that can be passed to `pip install` -
`plugin-name-on-pypi==<version>` and `git+https://github.com/user/repo@tag`
are the most popular ones. Specifying a version or tag is highly recommended.

For example, to install the PANGEO Plugin version 0.1 (if version 0.1 existed)
in your new TLJH install, you would use:

```bash
curl -L https://tljh.jupyter.org/bootstrap.py \
 | sudo python3 - \
   --plugin git+https://github.com/yuvipanda/tljh-pangeo@v0.1
```

Multiple plugins can be installed at once with: `--plugin <first-plugin-to-install> <second-plugin-to-install>`.

:::{note}
Plugins are extremely powerful and can do a large number of arbitrary things.
Only install plugins you trust.
:::