Handle LibreNMS plugins (#175)

Co-authored-by: CrazyMax <crazy-max@users.noreply.github.com>

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 21.2.0-r2 (2021/03/10)
+
+* Handle LibreNMS plugins (#171)
+
 ## 21.2.0-r1 (2021/03/04)
 
 * Switch to `yasu`

README.md

@@ -80,6 +80,7 @@ Image: librenms/librenms:latest
   * [LNMS command](doc/notes/lnms-command.md)
   * [Validate](doc/notes/validate.md)
   * [Dispatcher service](doc/notes/dispatcher-service.md)
+  * [Add a LibreNMS plugin](doc/notes/plugins.md)
   * [Syslog-ng](doc/notes/syslog-ng.md)
   * [Additional Monitoring plugins (Nagios)](doc/notes/additional-monitoring-plugins.md)
   * [Custom alert templates](doc/notes/alert-templates.md)

doc/docker/volumes.md

@@ -1,5 +1,6 @@
 ## Volumes
 
-* `/data`: Contains configuration, rrd database, logs, additional Monitoring plugins, additional syslog-ng config files
+* `/data`: Contains configuration, plugins, rrd database, logs, additional Monitoring plugins, additional syslog-ng config files
 
-> :warning: Note that the volume should be owned by the user/group with the specified `PUID` and `PGID`. If you don't give the volume correct permissions, the container may not start.
+> :warning: Note that the volume should be owned by the user/group with the specified `PUID` and `PGID`. If you don't
+> give the volume correct permissions, the container may not start.

doc/notes/plugins.md

@@ -0,0 +1,6 @@
+## Add a LibreNMS plugin
+
+You can add [plugins for LibreNMS](https://docs.librenms.org/Extensions/Plugin-System/) in `/data/plugins/`. If you
+add a plugin that already exists in LibreNMS, it will be removed and yours will be used (except for Weathermap).
+
+> ⚠️ Container has to be restarted to propagate changes

rootfs/etc/cont-init.d/03-config.sh

@@ -83,7 +83,7 @@ sed -i -e "s/RANDOMSTRINGGOESHERE/${LIBRENMS_SNMP_COMMUNITY}/" /etc/snmp/snmpd.c
 
 # Init files and folders
 echo "Initializing LibreNMS files / folders..."
-mkdir -p /data/config /data/logs /data/monitoring-plugins /data/rrd /data/weathermap /data/alert-templates
+mkdir -p /data/config /data/logs /data/monitoring-plugins /data/plugins /data/rrd /data/weathermap /data/alert-templates
 ln -sf /data/weathermap ${LIBRENMS_PATH}/html/plugins/Weathermap/configs
 touch /data/logs/librenms.log
 rm -rf ${LIBRENMS_PATH}/logs
@@ -185,9 +185,25 @@ cat > ${LIBRENMS_PATH}/config.d/dispatcher.php <<EOL
 \$config['service_watchdog_enabled'] = false;
 EOL
 
+# Check plugins
+echo "Checking LibreNMS plugins..."
+plugins=$(ls -l /data/plugins | egrep '^d' | awk '{print $9}')
+for plugin in ${plugins}; do
+  if [ "${plugin}" == "Weathermap" ]; then
+    echo "  WARNING: Plugin Weathermap cannot be overriden. Skipping..."
+    continue
+  fi
+  echo "  Linking plugin ${plugin}..."
+  if [ -d "${LIBRENMS_PATH}/html/plugins/${plugin}" ]; then
+    rm -rf "${LIBRENMS_PATH}/html/plugins/${plugin}"
+  fi
+  ln -sf "/data/plugins/${plugin}" "${LIBRENMS_PATH}/html/plugins/${plugin}"
+  chown -h librenms. "${LIBRENMS_PATH}/html/plugins/${plugin}"
+done
+
 # Fix perms
 echo "Fixing perms..."
-chown librenms. /data/config /data/monitoring-plugins /data/rrd /data/weathermap /data/alert-templates
+chown librenms. /data/config /data/monitoring-plugins /data/plugins /data/rrd /data/weathermap /data/alert-templates
 chown -R librenms. /data/logs ${LIBRENMS_PATH}/config.d ${LIBRENMS_PATH}/bootstrap ${LIBRENMS_PATH}/logs ${LIBRENMS_PATH}/storage
 chmod ug+rw /data/logs /data/rrd ${LIBRENMS_PATH}/bootstrap/cache ${LIBRENMS_PATH}/storage ${LIBRENMS_PATH}/storage/framework/*