barrier/dist/systemd/barrierc@.service.in

#  Barrier Client service barrierc-@BARRIER_VERSION@
#
#  This file is part of Barrier.
#
#  This is a systemd template service for the barrierc client service. Instances
#  are started using @<hostname>. For example:
#
#  Starting:
#   systemctl start barrierc@myserver
#  or:
#   systemctl start barrierc@myserver:24800
#
#  Enabling:
#   systemctl enable barrierc@myserver
#
#  SSL Fingerprints are stored in /var/lib/barrier@<hostname> for each client 
#  instance.

[Unit]
Description=Barrier Client connected to %I (Open-source KVM software)
Documentation=man:barrierc(1) man:barriers(1)
Documentation=https://github.com/debauchee/barrier/wiki
# Require network before starting barrierc
After=network-online.target
Wants=network-online.target
# Don't run client if server is running
Conflicts=barriers.service

[Service]
Type=exec
# Log level may be FATAL, ERROR, WARNING, NOTE, INFO, DEBUG, DEBUG1, DEBUG2
Environment=LOG_LEVEL=INFO
# Default display is :0
Environment=DISPLAY=:0
# Store fingerprints in instnace specific directories
Environment=XDG_DATA_HOME=/var/lib/barrier@%i
# TrustedServers.txt Directory
Environment=FP_DIR=/var/lib/barrier@%i/barrier/SSL/Fingerprints
# Ensure the Fingerprints directory exists
ExecStartPre=mkdir -p "${FP_DIR}"

# This uses openssl commands and grep to get the server's key and 
# store it in the TrustedServers.txt file. OpenSSL is a requirement
# for barrier on Linux so these commands should exist. This will only
# work if using the default 24800 port (since the port number must be
# specified for openssl)
ExecStartPre=sh -c "[ -f "${FP_DIR}/TrustedServers.txt" ] ||\
openssl s_client -connect %i:24800 2>/dev/null |\
openssl x509 -noout -sha1 -fingerprint |\
grep -oE '([A-Z0-9]{2}:?){20}' > ${FP_DIR}/TrustedServers.txt"

# Main executable
ExecStart=/usr/bin/barrierc --enable-crypto --display ${DISPLAY} --debug ${LOG_LEVEL} --no-daemon %i
# Restart on fail
Restart=always

[Install]
# Install to graphical target
WantedBy=graphical.target