prometheus: add nginx exception and sort postgresql backups

prometheus-entrouvert-exporter/prometheus-entrouvert-exporter.py

@@ -109,7 +109,7 @@ def munin(ctn):
 def nginx(ctn):
     try:
         r = requests.get("http://localhost/nginx_status")
-    except requests.exceptions.SSLError:
+    except (requests.exceptions.SSLError, requests.exceptions.ConnectionError):
         return
     if r.ok:
         for line in r.text.splitlines():
@@ -142,7 +142,8 @@ def postgresql(ctn):
         backup_files = glob.glob('/var/lib/postgresql/backups/base/*')
         if not backup_files:
             return -1
-        created = os.stat(backup_files.sort(key=os.path.getmtime)[-1]).st_ctime
+        sorted_backup_files = sorted(backup_files, key=os.path.getmtime)
+        created = os.stat(sorted_backup_files[-1]).st_ctime
         return((datetime.datetime.now() - datetime.datetime.fromtimestamp(created)).seconds)
 
     recovery = glob.glob("/var/lib/postgresql/*/*/recovery.conf")