Add munin plugin to show connections and file descriptors

NEWS.md

@@ -3,6 +3,7 @@
 * Fixed problem identifying OAuth request protocol
 * Make base url configurable
 * Update underscore dependency 
+* Add munin plugin
 
 1.3.9
 -----

tools/munin/Makefile

@@ -0,0 +1,19 @@
+MUNIN_PLUGINS_DIR=/etc/munin/plugins
+MUNIN_PLUGINS_CONFIG_DIR=/etc/munin/plugin-conf.d
+PWD=$(shell pwd)
+
+all: cdbsqlapi.conf
+
+cdbsqlapi.conf: cdbsqlapi.conf.in
+	sed 's#@PWD@#$(PWD)#' < $< > $@
+
+install-munin-plugin-conf: cdbsqlapi.conf 
+	install -m 644 $< $(MUNIN_PLUGINS_CONFIG_DIR)/cdbsqlapi.conf
+
+install-munin-plugin: cdbsqlapi
+	install -m 755 $< $(MUNIN_PLUGINS_DIR)/cdbsqlapi
+
+install: install-munin-plugin install-munin-plugin-conf
+
+clean:
+	rm -f cdbsqlapi.conf

tools/munin/cdbsqlapi

@@ -0,0 +1,74 @@
+#!/bin/sh
+
+envnik=$(basename "${SQLAPI_ENVIRONMENT}" .js)
+
+if test "$1" = "config"; then
+echo "graph_title fd usage (${envnik})"
+cat <<"EOM"
+graph_vlabel number of file descriptors
+graph_category sqlapi
+graph_scale no
+procs.label Number of worker processes
+pgsql.label PostgreSQL connections (max)
+redis.label Redis connections (max)
+http.label Incoming http requests (max)
+nfd.label Total file descriptors (max)
+EOM
+exit 0
+fi
+
+if test x"$1" != x; then
+  SQLAPI_ENVIRONMENT=$(cd $(dirname $0); pwd)/../../config/environments/${1}.js
+fi
+
+if test -z "$SQLAPI_ENVIRONMENT"; then
+  echo "Usage: $0 [<environment>]" >&2
+  echo "   or: [SQLAPI_ENVIRONMENT=<environment>] $0" >&2
+  exit 1
+fi
+
+http_port=$(echo "console.log(require('${SQLAPI_ENVIRONMENT}').node_port)" | node) || exit 1
+pgsql_port=$(echo "console.log(require('${SQLAPI_ENVIRONMENT}').db_port)" | node) || exit 1
+redis_port=$(echo "console.log(require('${SQLAPI_ENVIRONMENT}').redis_port)" | node) || exit 1
+
+pids=$(lsof -i :${http_port} | grep LISTEN | awk '{print $2}')
+nworkers=$(echo "${pids}" | wc -l)
+pids=$(echo "${pids}" | paste -sd ' ')
+
+if test -z "${pids}"; then
+  echo "No processes found listening on tcp port '${http_port}'" >&2
+  exit 1
+fi
+
+tmpreport="/tmp/checkfd.$$.txt"
+
+lsof -Pp $(echo "${pids}" | tr ' ' ',') > "${tmpreport}"
+
+maxdb=0
+maxredis=0
+maxhttp=0
+maxtot=0
+
+for pid in ${pids}; do
+
+  cnt=$(grep "${pid}" "${tmpreport}" | grep ":${pgsql_port} " | wc -l);
+  if test $cnt -gt $maxdb; then maxdb=$cnt; fi
+  
+  cnt=$(grep "${pid}" "${tmpreport}" | grep ":${redis_port} " | wc -l);
+  if test $cnt -gt $maxredis; then maxredis=$cnt; fi
+
+  cnt=$(grep "${pid}" "${tmpreport}" | grep ":${http_port}-" | grep -v "LISTEN" | wc -l);
+  if test $cnt -gt $maxhttp; then maxhttp=$cnt; fi
+
+  cnt=$(grep "${pid}" "${tmpreport}" | wc -l);
+  if test $cnt -gt $maxtot; then maxtot=$cnt; fi
+
+done
+
+echo "procs.value ${nworkers}"
+echo "pgsql.value ${maxdb}"
+echo "redis.value ${maxredis}"
+echo "http.value ${maxhttp}"
+echo "nfd.value ${maxtot}"
+
+rm -f "${tmpreport}"

tools/munin/cdbsqlapi.conf.in

@@ -0,0 +1,5 @@
+# Configuration file for munin plugin
+
+[cdbsqlapi]
+user root
+env.SQLAPI_ENVIRONMENT @PWD@/../../config/environments/production.js