[Unit]
Description=Lemmy: UI Daemon
After=network.target

[Service]
Type=simple
User=__APP__
Group=__APP__
Environment="LEMMY_INTERNAL_HOST=127.0.0.1:__PORT__"
Environment="LEMMY_EXTERNAL_HOST=__DOMAIN__"
Environment="LEMMY_HTTPS=true"
Environment="LEMMY_UI_HOST=0.0.0.0:__PORT_UI__"
WorkingDirectory=__INSTALL_DIR__/lemmy-ui/
ExecStart=__YNH_NODE__ dist/js/server.js
StandardOutput=append:/var/log/__APP__/__APP__-ui.log
StandardError=inherit
Restart=always

# Sandboxing options to harden security
# Depending on specificities of your service/app, you may need to tweak these 
# .. but this should be a good baseline
# Details for these options: https://www.freedesktop.org/software/systemd/man/systemd.exec.html
NoNewPrivileges=yes
PrivateTmp=yes
PrivateDevices=yes
RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
RestrictNamespaces=yes
RestrictRealtime=yes
DevicePolicy=closed
ProtectSystem=full
ProtectControlGroups=yes
ProtectKernelModules=yes
ProtectKernelTunables=yes
LockPersonality=yes
SystemCallFilter=~@clock @debug @module @mount @obsolete @reboot @setuid @swap

# Denying access to capabilities that should not be relevant for webapps
# Doc: https://man7.org/linux/man-pages/man7/capabilities.7.html
CapabilityBoundingSet=~CAP_RAWIO CAP_MKNOD
CapabilityBoundingSet=~CAP_AUDIT_CONTROL CAP_AUDIT_READ CAP_AUDIT_WRITE
CapabilityBoundingSet=~CAP_SYS_BOOT CAP_SYS_TIME CAP_SYS_MODULE CAP_SYS_PACCT
CapabilityBoundingSet=~CAP_LEASE CAP_LINUX_IMMUTABLE CAP_IPC_LOCK
CapabilityBoundingSet=~CAP_BLOCK_SUSPEND CAP_WAKE_ALARM
CapabilityBoundingSet=~CAP_SYS_TTY_CONFIG
CapabilityBoundingSet=~CAP_MAC_ADMIN CAP_MAC_OVERRIDE
CapabilityBoundingSet=~CAP_NET_ADMIN CAP_NET_BROADCAST CAP_NET_RAW
CapabilityBoundingSet=~CAP_SYS_ADMIN CAP_SYS_PTRACE CAP_SYSLOG 

[Install]
WantedBy=multi-user.target