spacecookie: Gopher Library and Server Daemon

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|____/| .__/ \__,_|\___\___|\___\___/ \___/|_|\_\_|\___|
      |_|    – haskell gopher server

What is Gopher?

The Gopher protocol /ˈɡoʊfər/ is a TCP/IP application layer protocol designed for distributing, searching, and retrieving documents over the Internet. The Gopher protocol was strongly oriented towards a menu-document design and presented an alternative to the World Wide Web in its early stages, but ultimately HTTP became the dominant protocol. The Gopher ecosystem is often regarded as the effective predecessor of the World Wide Web.

– WP

What is Spacecookie?

Spacecookie is a gopher server and…

• is RFC1436-compliant
• supports info-line in menus (compatible protocol extension)
• supports gophermaps (see below)
• provides a library for custom gopher applications (see documentation)
• can integrate with systemd using socket activation

Configuration

In order to run your new gopher server, you got to configure it first. The example configuration file is ./etc/spacecookie.json.

Let's have a quick look at the options:

Running

After you've created your config file just start spacecookie like this:

spacecookie /path/to/spacecookie.json

Spacecookie runs as a simple process and doesn't fork or write a PID file. Therefore you'll need to use a supervisor to run it as a proper daemon.

With systemd

Spacecookie supports systemd socket activation. To set it up you'll need to install spacecookie.service and spacecookie.socket like so:

cp ./etc/spacecookie.{service,socket} /etc/systemd/system/
systemctl daemon-reload
systemctl enable spacecookie.socket
systemctl start  spacecookie.socket
systemctl start  spacecookie.service # optional, started by the socket automatically if needed

You'll have to ensure that the paths are correct and the user and group specified in spacecookie.socket and spacecookie.service exist.

Without systemd

Spacecookie does not require systemd nor depend on it. Since socket activation only uses an environment variable and a type unix socket, it is very lightweight and can be utilized without using a systemd library or dbus.

For example, it should be pretty easy to write a runit service file.

Adding Content

Spacecookie acts as a simple file server, only excluding files that start with a dot. It generates gopher menus automatically; however you can use custom ones by adding a gophermap file.

Spacecookie checks for .gophermap in every directory it serves and, if present, uses the menu specified in there.

Such a file looks like this:

You can just start writing text that
will be displayed by the gopher client
without a link to a file. Empty lines are
also possible.

1Menu Entry for a directory full of funny stuff	/funny
iFunny Image	/funy.jpg
gcat gif	/cat.gif
0about me	/about.txt
1Floodgap's gopher server	/	gopher.floodgap.com	70

So what does that all mean? These are the rules for a gophermap file:

• comment lines (called info lines in spacecookie's code) are just lines of text. They must not contain a tab! They will be displayed as lines of text by the gopher client.
• menu entries for files or directories start with a single char which specifies the file type, followed by the text for that file without a space or tab between them! Then the path is added after a tab.
• "Links" to other servers are like file/directory menu entries but the server's hostname and its port must be added (tab-separated).

The file type characters are defined in RFC1436. Detailed documentation on the gophermap format can be found here.

Portability

Spacecookie's portability is mostly limited by haskell-socket. haskell-socket should work on any POSIX-compliant Operating system, so Spacecookie should support those platforms as well.

However I personally have only tested Spacecookie on GNU/Linux (with and without systemd) so far. Feel free to send me an email or generate a build report if you've built spacecookie (or failed to do so) on another platform!

Windows is currently not supported as we use some Unix-specific features, but there is probably little demand for it as well.

HTTP Support?

Spacecookie will never support HTTP to keep the code simple and clean. You can however use an HTTP to Gopher Proxy with Spacecookie just fine. Any proxy supporting RFC1436 should work, my own gopher-proxy might work for you.