[Unit]
Description=Mosquitto MQTT broker
Documentation=https://mosquitto.org/documentation/
After=network.target var-lib-virtiofs-data.mount
Requires=var-lib-virtiofs-data.mount

# Only start once Mosquitto has been configured (the operator provides the password file)
ConditionPathExists=/etc/quadlets/mosquitto/passwd

# Start/stop this unit when the target is started/stopped
PartOf=mosquitto.target

[Container]
ContainerName=mosquitto
Image=mosquitto.image
AutoUpdate=registry

# No need for root privileges: the broker binds 1883 (> 1024) as an unprivileged user.
# The upstream entrypoint only chowns /mosquitto when it runs as root; as UID 10033 it
# just execs the broker, so every directory it touches must already be owned by 10033:10000
# (that is what tmpfiles.d and the config install ownership take care of).
User=10033
Group=10000

# Network configuration (host networking is the convention across this repository)
Network=host

# Run the broker against the packaged configuration. Host and container paths are kept
# identical so that password_file, acl_file, persistence_location and include_dir all
# resolve to the same location inside and outside the container.
Exec=/usr/sbin/mosquitto -c /etc/quadlets/mosquitto/mosquitto.conf

# Configuration (read-only): mosquitto.conf, conf.d/ fragments and the operator-provided
# passwd / acl files all live under /etc/quadlets/mosquitto.
Volume=/etc/quadlets/mosquitto:/etc/quadlets/mosquitto:ro,Z

# Precious data (retained messages + client sessions) on the virtiofs mount, so the
# host's ZFS snapshots and backups pick it up.
Volume=/var/lib/virtiofs/data/mosquitto:/var/lib/virtiofs/data/mosquitto:z

# Health check: a bare TCP connect to the listener. It needs no credentials (which the
# operator may not have provided yet), which is why it is preferred over a credentialed
# mosquitto_sub on $SYS/#.
HealthCmd=nc -z 127.0.0.1 1883
HealthInterval=30s
HealthTimeout=5s
HealthStartPeriod=10s
HealthRetries=3

[Service]
Restart=always
RestartSec=10
TimeoutStartSec=120
TimeoutStopSec=30

[Install]
WantedBy=mosquitto.target