Lupa Pona

Lupa Pona serves the local directory as a Gemini site.

It's a super simple server: it just serves the current directory. I use Phoebe myself, for Gemini hosting. It's a wiki, not just a file server.

Let me know if you want to use Lupa Pona in a multi-user or virtual-hosting setup. All the necessary bits can be lifted from elsewhere. Right now, I'm just using Lupa Pona to temporarily serve a local directory, as one might occasionally use a few lines of Python to serve the local directory over the web using SimpleHTTPServer.

Table of Contents

• Limitations
• Dependencies
• Quickstart
• Troubleshooting
• Options
• Using systemd
• Privacy

Limitations

Currently, all files are served as text/gemini; charset=UTF-8.

Dependencies

Perl libraries you need to install if you want to run Lupa Pona:

• Mojo::Log and Mojo::IOLoop, or libmojolicious-perl
• IO::Socket::SSL, or libio-socket-ssl-perl
• File::Slurper, or libfile-slurper-perl
• Modern::Perl, or libmodern-perl-perl
• URI::Escape, or liburi-escape-xs-perl

Quickstart

Since Lupa Pona traffic is encrypted, we need to generate a certificate and a key. When you start it for the first time, it will ask you for a hostname. Use 'localhost' if you don't know. You can also generate your own certificate, like this, replacing $hostname with whatever you need:

openssl req -new -x509 -newkey ec -subj "/CN=$hostname" \
-pkeyopt ec_paramgen_curve:prime256v1 \
-days 1825 -nodes -out cert.pem -keyout key.pem

This creates a certificate and a private key, both of them unencrypted, using eliptic curves of a particular kind, valid for five years.

Start the server:

lupa-pona

This starts the server in the foreground, for gemini://localhost:1965. If it aborts, see the "Troubleshooting" section below. If it runs, open your favourite Gemini client and test it, or open another terminal and test it:

echo gemini://localhost \
  | openssl s_client --quiet --connect localhost:1965 2>/dev/null

You should see a Gemini page starting with the following:

20 text/gemini; charset=UTF-8
Welcome to Lupa Pona!

Success!! 😀 🚀🚀

Troubleshooting

No trouble, yet!

Options

These are the options Lupa Pona knows about:

• --host is the address to use; the default is 0.0.0.0, i.e. accepting all connections (use this option if your machine is reachable via multiple names, e.g. alexschroeder.ch and emacswiki.org and you just want want to serve one of them)
• --port is the port to use; the default is 1965
• --text_encoding is the text encoding to use if you're not going to use UTF-8 (consider adding support for Encode::Guess)
• --log_level is the log level to use (error, warn, info, debug, trace); the default is warn
• --cert_file is the certificate file to use; the default is cert.pem
• --key_file is the key file to use; the default is key.pem

Using systemd

Systemd is going to handle daemonisation for us. There's more documentation available online.

You could create a specific user:

sudo adduser --disabled-login --disabled-password lupa-pona

Copy Lupa Pona to /home/lupa-pona/lupa-pona.

Basically, this is the template for our service:

[Unit]
Description=Lupa Pona
After=network.target
[Service]
Type=simple
WorkingDirectory=/home/lupa-pona
ExecStart=/home/lupa-pona/lupa-pona
Restart=always
User=lupa-pona
Group=lupa-pona
[Install]
WantedBy=multi-user.target

Save this as lupa-pona.service, and then link it:

sudo ln -s /home/lupa-pona/lupa-pona.service /etc/systemd/system/

Reload systemd:

sudo systemctl daemon-reload

Start Lupa Pona:

sudo systemctl start lupa-pona

Check the log output:

sudo journalctl --unit lupa-pona

All the files in /home/lupa-pona are going to be served, if the lupa-pona user can read them.

Privacy

If you increase the log level, the server will produce more output, including information about the connections happening, like 2020/06/29-15:35:59 CONNECT SSL Peer: "[::1]:52730" Local: "[::1]:1965" and the like (in this case ::1 is my local address so that isn't too useful but it could also be your visitor's IP numbers, in which case you will need to tell them about it using in order to comply with the GDPR.