added nagios script

Author: FreakyBytes

README.md

@@ -10,6 +10,12 @@ A demo is currently hosted on our server. *No need for registration!*
 ## Development
 The development is currently coordinated at our [trac project management](https://sems.uni-rostock.de/trac/combinearchive-web).
 
+## Additional Resources
+Some helpful resources can be found in the resources folder. It contains a default context configuration for tomcat, a default
+VHost configuration for the Apache WebServer and a folder called "nagios" containing a simple python3 script for nagios, to
+check if the webCAT instance is up and running. In case a stats secret is provided (and configured in the python script) it
+also checks for the maximum space quota.
+
 ## Licence
 CombineArchiveWeb - a WebInterface to read/create/write/manipulate/... COMBINE archives
 Copyright (C) 2014-2015:

resources/nagios/checkWebCat.py

@@ -0,0 +1,56 @@
+#!/usr/bin/python3
+
+import os, sys, json, time, math
+import requests
+
+# settings
+url = "http://localhost:8080/CombineArchiveWeb/rest/v1/stats"
+secret = "1234"
+timeout = 0.02
+
+# trying to establish connection
+try:
+	req = requests.get(url, params=[("secret", secret)], timeout=timeout)
+	stats = req.json()
+except requests.exceptions.ConnectionError as err:
+	print( "Connection Error: {0}".format(err) )
+	sys.exit(2)
+except requests.exceptions.HTTPError as err:
+	print( "HTTP Error: {0}".format(err) )
+	sys.exit(2)
+except requests.exceptions.Timeout as err:
+	print( "Timeout of {1} exceeded: {0}".format(err, timeout) )
+	sys.exit(2)
+except requests.exceptions.TooManyRedirects as err:
+	print( "Too many redirects while requesting stats: {0}".format(err) )
+	sys.exit(2)
+except ValueError as err:
+	print( "Error decoding json: {0}".format(err) )
+	sys.exit(2)
+except:
+	print( "Unknown exception: {0}".format(sys.exc_info()[0]) )
+	sys.exit(2)
+	
+if 'maxStatsAge' and 'generated' in stats:
+	now = int( time.time() ) * 1000
+	if math.fabs( now - int(stats['generated']) ) >= int(stats['maxStatsAge']) * 1000 :
+		print( "Stats are too old. Is System running?" )
+		sys.exit(1)
+
+if 'totalSizeQuota' in stats:
+	if stats['totalSizeQuota'] >= 0.90: 
+		print("Total quoata is about to exceed: {0}%".format(stats['totalSizeQuota']*100) )
+		sys.exit(1)
+	elif stats['totalSizeQuota'] >= 0.99:
+		print( "Total quota is exceeded: {0}%".format(stats['totalSizeQuota']*100) )
+		sys.exit(2)
+	else:
+		print("quota is ok: {0}% ".format(stats['totalSizeQuota']*100) )
+		sys.exit(0)
+else:
+	sys.exit(0)
+
+
+# no normal ending
+print( "script terminated unexpected" )
+sys.exit(2)