mtmediasrv

A Minetest Media server implementation as fcgi server.

This program is useful to distribute minetest media (textures, models, sounds) to minetest clients for multiplayer server owners that wish to have their media hosted on a remote media server URL. Doing this as a separate download removes some of the download bandwidth from the actual game server and offloads it to a different HTTP server. This will work for clients that have cURL support enabled.

Requirements

• nginx or apache, with fcgi
• webserver must be able to access file sockets in /run/mtmediasrv
• systemd for controlling the service startup
• mod assets to serve

Optionally, if you want to compile the source yourself:

• go to build the service

Binary builds are available for Linux under releases on the github project. Other OS builds can be added on request, but the code is intended to run headless on a Linux server.

This program is intended to run as fcgi process and handle POST requests for the /index.mth URI. It listens on a local unix domain socket, and needs to read the media files in the media folder to create sha1 hashes. It creates a hash list of files it has available and keeps this in memory.

At startup, the program can optionally scan mods and subgames to find and copy or hardlink (the default) all the assets into the webroot. The hardlink method is better for space, but may fail if the media is not on the same filesystem as the webroot.

When a client connects, the client POSTS their list of known sha1 hashes of files they need.

The program verifies for each needed hash that the server has the hash listed, and returns the needed hashes only, and only hashes that it has the files for.

The actual file content is not served by this program, for this you need to have your web server serve that content as static files.

Building

Note that binaries are available in the releases section of the github project.

mtmediasrv uses viper to read configuration files. You must go get https://github.com/spf13/viper before building. Run make in this folder to create the binary mtschemsrv.

Installation

Several example config and service units are provided as an example on how to deploy this service.

It is recommended to use the mtmediasrv.service and cp that file to /etc/systemd/system, and then enable it with systemctl daemon-reload; systemctl enable mtmediasrv.

Copy the mtmediasrv.yaml file to /etc/, and configure the paths to point to the right locations. Your webroot should be empty, as it will be filled by the daemon automatically.

Once you have configured your web server properly so that it serves up the static content files by hash, point the mtmediasrv to the same folder and it will talk to minetest clients that request media automatically. If the content changes, you need to restart the program.

You should not have a file called index.mth in the media folder, although this will not break anything, it will probably be confusing.

Copy and edit the mtmediasrv.yaml file and point it at the proper webroot, socket path, and mediapath entries. Place it in /etc/ or ~/.config/.

Once everything is in place, do systemctl start mtmediasrv and check the output of journalctl -u mtmediasrv for errors and log output.

logging

The program logs all clients and writes out the following data to the log output (journal/syslog):

• remote address
• user agent
• hashes needed/hashes given
• content-length of sent bytes

Example output:

mtmediasrv: 5.4.3.2:34567 'Minetest/0.4.15 (Linux/4.10.1 x86_64)' 64/64 1286