Add RPM spec file and systemd service unit. (#26)

* Add RPM spec file and systemd service unit.

* Move to packaging/rpm

---------

Co-authored-by: Matt Mix <mattmix@umn.edu>
Co-authored-by: mattmix <mattmix@andor.local>

packaging/rpm/cgroup_exporter.service

@@ -0,0 +1,32 @@
+[Unit]
+Description=cgroup exporter
+After=network.target network-online.target
+
+[Service]
+Type=simple
+EnvironmentFile=-/etc/sysconfig/cgroup_exporter
+ExecStart=/usr/sbin/cgroup_exporter --config.paths $CONFIG_PATHS $OPTIONS
+Restart=always
+User=cgroup_exporter
+Group=cgroup_exporter
+NoNewPrivileges=yes
+PrivateTmp=yes
+PrivateDevices=yes
+DevicePolicy=closed
+ProtectSystem=strict
+ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelModules=yes
+ProtectKernelTunables=yes
+RestrictAddressFamilies=AF_INET AF_INET6
+RestrictNamespaces=yes
+RestrictRealtime=yes
+RestrictSUIDSGID=yes
+MemoryDenyWriteExecute=yes
+LockPersonality=yes
+RemoveIPC=yes
+CapabilityBoundingSet=
+SystemCallFilter=@system-service 
+
+[Install]
+WantedBy=multi-user.target

packaging/rpm/cgroup_exporter.spec

@@ -0,0 +1,45 @@
+Name:           cgroup_exporter
+Version:        0.9.1
+Release:        1%{?dist}
+Summary:        The cgroup_exporter produces metrics from cgroups.
+
+License:        Apache License
+Source0:        %{name}-%{version}.tar.gz
+URL:            https://github.com/treydock/cgroup_exporter
+
+BuildRequires:  go-toolset
+Requires:       systemd
+
+%description
+
+The cgroup_exporter produces metrics from cgroups.
+
+This exporter by default listens on port 9306 and all metrics are exposed via the /metrics endpoint.
+
+%global debug_package %{nil}
+
+%prep
+%autosetup
+
+%build
+go build -v -o %{name}
+
+%install
+install -Dpm 0755 %{name} %{buildroot}%{_sbindir}/%{name}
+install -Dpm 0644 packaging/rpm/%{name}.service %{buildroot}%{_unitdir}/%{name}.service
+install -Dpm 0644 packaging/rpm/%{name}.sysconfig %{buildroot}%{_sysconfdir}/sysconfig/%{name}
+
+%clean
+rm -rf %{buildroot}
+
+%pre
+%{_sbindir}/useradd -c "cgroup exporter user" -s /bin/false -r -d / cgroup_exporter 2>/dev/null || :
+
+%files
+%{_sbindir}/%{name}
+%{_unitdir}/%{name}.service
+%config(noreplace) %{_sysconfdir}/sysconfig/%{name}
+
+%changelog
+* Fri Nov 10 2023 Initial RPM
+- 

packaging/rpm/cgroup_exporter.sysconfig

@@ -0,0 +1,4 @@
+# cgroup subsystem paths to look at, comma separated
+CONFIG_PATHS=/user.slice
+# Additional options
+OPTIONS=