Add systemd service (#540)

pgcat.service

@@ -0,0 +1,16 @@
+[Unit]
+Description=PgCat pooler
+After=network.target
+StartLimitIntervalSec=0
+
+[Service]
+User=pgcat
+Type=simple
+Restart=always
+RestartSec=1
+Environment=RUST_LOG=info
+LimitNOFILE=65536
+ExecStart=/usr/bin/pgcat /etc/pgcat.toml
+
+[Install]
+WantedBy=multi-user.target

postinst

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+systemctl daemon-reload
+systemctl enable pgcat

postrm

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+systemctl daemon-reload

prerm

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+systemctl stop pgcat
+systemctl disable pgcat

utilities/deb.sh

@@ -17,14 +17,21 @@ cargo build --release
 rm -rf "$deb_dir"
 mkdir -p "$deb_dir/DEBIAN"
 mkdir -p "$deb_dir/usr/bin"
-mkdir -p "$deb_dir/etc"
+mkdir -p "$deb_dir/etc/systemd/system"
 
 cp target/release/pgcat "$deb_dir/usr/bin/pgcat"
 chmod +x "$deb_dir/usr/bin/pgcat"
 
 cp pgcat.toml "$deb_dir/etc/pgcat.toml"
+cp pgcat.service "$deb_dir/etc/systemd/system/pgcat.service"
 
 (cat control | envsubst) > "$deb_dir/DEBIAN/control"
+cp postinst "$deb_dir/DEBIAN/postinst"
+cp postrm "$deb_dir/DEBIAN/postrm"
+cp prerm "$deb_dir/DEBIAN/prerm"
+
+chmod +x ${deb_dir}/DEBIAN/post*
+chmod +x ${deb_dir}/DEBIAN/pre*
 
 dpkg-deb \
   --root-owner-group \