/fmsgd

fmsg host

Primary LanguageGo

fmsgd

go 1.19

Implementation of fmsg host written in go! Uses local filesystem and PostgreSQL database to store messages per the fmsg-store-postgres standard.

Building from source

Tested with go 1.18, 1.19 and 1.20 on Linux (AMD64, ARM64) and Windows AMD64

  1. Clone this repository
  2. Navigate to src/
  3. Run go build .

Environment

fmsgd uses environment variables as a control surface. FMSG_DATA_DIR, FMSG_DOMAIN and FMSG_ID_URL are required to be set; otherwise the host will fail to start. In addition to these FMSG_ varibles, PG variables need to be set for the PostgreSQL database to use, refer to: https://www.postgresql.org/docs/current/libpq-envars.html

Variable Default Description
FMSG_DATA_DIR Path where messages will be stored. e.g. /opt/fmsg/data
FMSG_DOMAIN Domain name this host is located. e.g. example.com
FMSG_ID_URL Base HTTP URL for fmsg Id API, e.g. http://localhost:5000
FMSG_MAX_MSG_SIZE 10240 Bytes. Maximum size above which to reject messages greater than before downloading them.
FMSG_PORT 36900 TCP port to listen on
FMSG_MAX_PAST_TIME_DELTA 604800 Seconds. Duration since message timestamp to reject if greater than. Note sending host could have been holding messages waiting for us to be reachable.
FMSG_MAX_FUTURE_TIME_DELTA 300 Seconds. Duration from message timestamp to reject if greater than.
FMSG_MIN_DOWNLOAD_RATE 5000 Bytes per second. Used in setting download deadlines while downloading a message.
FMSG_MIN_UPLOAD_RATE 5000 Bytes per second. Used in setting upload deadlines while sending a message.
FMSG_READ_BUFFER_SIZE 1600 Bytes. Internal read buffer size per incoming connection

Running

IP address to bind to and listen on must be supplied as the first argument, e.g.:

./fmsgd "0.0.0.0"

systemd

An example systemd service to run fmsgd as a service on startup

ASSUMES:

  • Directory /opt/fmsgd has been created and contains built executable: fmsgd
  • Text file /opt/fmsgd/env exists containing environment variables
  • User fmsg has been created and has
    • read and execute permissions to /opt/fmsgd/, e.g. with chown -R fmsg:fmsg /opt/fmsgd after mkdir /opt/fmsgd
    • write permissions to FMSG_DATA_DIR

/etc/systemd/system/fmsgd.service

[Unit]
Description=fmsg Host
After=network.target

[Service]
EnvironmentFile=/opt/fmsgd/env
ExecStart=/opt/fmsgd/fmsgd "0.0.0.0"
User=fmsg
Group=fmsg

[Install]
WantedBy=multi-user.target

sudo systemctl daemon-reload
sudo systemctl enable fmsgd
sudo systemctl start fmsgd