Added nginx check for upstream access times

plugins/nginx/nginx_upstream

@@ -0,0 +1,56 @@
+#!/usr/bin/python
+#requires log format as below
+#log_format cache '$remote_addr - $host [$time_local] "$request" $status '
+#                 '$body_bytes_sent "$http_referer" '
+#                 'rt=$request_time ut="$upstream_response_time" '
+#                 'cs=$upstream_cache_status';
+
+#License BSD
+#Created by Simon Whittaker simon+github@swbh.net
+#based on nginx_cache_hit_rate
+
+from __future__ import with_statement
+import re
+import sys
+fname = "/var/log/nginx/access.log"     # File to check
+
+if len(sys.argv) > 1:
+        if sys.argv[1]=="config":
+                print "graph_args --base 1000 -l 0"
+                print "graph_title NGINX Upstream times"
+                print "graph_category nginx"
+                print "graph_vlabel milliseconds"
+                print "upstream.label upstream"
+                print "upstream.warning 5000"
+                print "upstream.critical 10000"
+                print "graph_info Shows the average time of connections to upstream servers for the primary site"
+                sys.exit(0)
+
+with open(fname, "r") as f:
+    f.seek (0, 2)           # Seek @ EOF
+    fsize = f.tell()        # Get Size
+    f.seek (max (fsize-20480, 0), 0) # Set pos @ last n chars
+    lines = f.readlines()       # Read to end
+
+lines = lines[-1000:] #last 1000 lines you might want to change this
+
+re1='.*?'       # Non-greedy match on filler
+re2='(ut)'      # Word 1
+re3='(=)'       # Any Single Character 1
+re4='([+-]?\\d*\\.\\d+)(?![-+0-9\\.])'  # Float 1
+
+rg = re.compile(re1+re2+re3+re4,re.IGNORECASE|re.DOTALL)
+totaltimeforrequests=0
+numberofrequests=0
+for line in lines:
+        m = rg.search(line)
+        if m:   
+                word1=m.group(1)
+                c1=m.group(2)
+                float1=m.group(3)
+                numberofrequests=numberofrequests+1
+                totaltimeforrequests=totaltimeforrequests+float(float1)
+
+upstream=(totaltimeforrequests/numberofrequests)*1000
+upstream=int(upstream)
+print "upstream.value "+str(upstream)