Add Debian packaging support with cargo-deb

- Add cargo-deb metadata to socktop and socktop_agent Cargo.toml
- Create systemd service file for socktop_agent
- Add postinst/postrm maintainer scripts for user/group management
- Create GitHub Actions workflow to build .deb packages for AMD64 and ARM64
- Add comprehensive documentation in docs/DEBIAN_PACKAGING.md
- Packages will be available as artifacts on every push
- Automatic GitHub releases for version tags

socktop_agent/Cargo.toml

@@ -6,6 +6,8 @@ description = "Socktop agent daemon. Serves host metrics over WebSocket."
 edition = "2024"
 license = "MIT"
 readme = "README.md"
+homepage = "https://github.com/jasonwitty/socktop"
+repository = "https://github.com/jasonwitty/socktop"
 
 [dependencies]
 # Tokio: Use minimal features instead of "full" to reduce binary size
@@ -45,3 +47,21 @@ protoc-bin-vendored = "3"
 assert_cmd = "2.0"
 tempfile = "3.10"
 tokio-tungstenite = "0.21"
+
+[package.metadata.deb]
+maintainer = "Jason Witty <jasonpwitty+socktop@proton.me>"
+copyright = "2024, Jason Witty <jasonpwitty+socktop@proton.me>"
+license-file = ["../LICENSE", "4"]
+extended-description = """\
+socktop_agent is the daemon component that runs on remote hosts to collect \
+and serve system metrics over WebSocket. It gathers CPU, memory, disk, network, \
+GPU, and process information that can be monitored remotely by the socktop TUI client."""
+depends = "$auto"
+section = "admin"
+priority = "optional"
+assets = [
+    ["target/release/socktop_agent", "usr/bin/", "755"],
+    ["../README.md", "usr/share/doc/socktop_agent/", "644"],
+]
+maintainer-scripts = "debian/"
+systemd-units = { unit-name = "socktop-agent", unit-scripts = ".", enable = false }

socktop_agent/debian/postinst

@@ -0,0 +1,26 @@
+#!/bin/sh
+set -e
+
+# Create socktop user and group if they don't exist
+if ! getent group socktop >/dev/null; then
+    addgroup --system socktop
+fi
+
+if ! getent passwd socktop >/dev/null; then
+    adduser --system --ingroup socktop --home /var/lib/socktop \
+            --no-create-home --disabled-password --disabled-login \
+            --gecos "Socktop Agent" socktop
+fi
+
+# Create state directory
+mkdir -p /var/lib/socktop
+chown socktop:socktop /var/lib/socktop
+chmod 755 /var/lib/socktop
+
+# Create config directory if it doesn't exist
+mkdir -p /etc/socktop
+chmod 755 /etc/socktop
+
+#DEBHELPER#
+
+exit 0

socktop_agent/debian/postrm

@@ -0,0 +1,34 @@
+#!/bin/sh
+set -e
+
+case "$1" in
+    purge)
+        # Remove user and group on purge
+        if getent passwd socktop >/dev/null; then
+            deluser --quiet socktop || true
+        fi
+
+        if getent group socktop >/dev/null; then
+            delgroup --quiet socktop || true
+        fi
+
+        # Remove state directory on purge
+        rm -rf /var/lib/socktop
+
+        # Remove config directory if empty
+        rmdir --ignore-fail-on-non-empty /etc/socktop 2>/dev/null || true
+        ;;
+
+    remove|upgrade|failed-upgrade|abort-install|abort-upgrade|disappear)
+        # Do nothing on remove/upgrade
+        ;;
+
+    *)
+        echo "postrm called with unknown argument \`$1'" >&2
+        exit 1
+        ;;
+esac
+
+#DEBHELPER#
+
+exit 0

socktop_agent/socktop-agent.service

@@ -0,0 +1,27 @@
+[Unit]
+Description=Socktop Agent - Remote System Monitor
+Documentation=https://github.com/jasonwitty/socktop
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/socktop_agent --port 3000
+Environment=RUST_LOG=info
+# Optional authentication token:
+# Environment=SOCKTOP_TOKEN=changeme
+Restart=on-failure
+RestartSec=5
+User=socktop
+Group=socktop
+NoNewPrivileges=true
+
+# Security hardening
+PrivateTmp=true
+ProtectSystem=strict
+ProtectHome=true
+ReadWritePaths=/var/lib/socktop
+StateDirectory=socktop
+
+[Install]
+WantedBy=multi-user.target