added login ticket cache

PVEApi.py

@@ -5,7 +5,9 @@ import json
 from VM import VM
 from Node import Node
 from Storage import Storage
+import time
 
+CACHEFILE='/tmp/zabbix_ticket.json'
 
 def get_auth(host, username, password):
     """
@@ -37,8 +39,46 @@ class PVEApi(object):
         """
         self.host = host
         self.url = "https://" + self.host + "/api2/json"
+        if self.check_cacheexpire():
             self.csrftoken = get_auth(self.host, username, password)[0]
             self.ticket = get_auth(self.host, username, password)[1]
+            self.write_ticketcache()
+        else:
+            self.csrftoken = self.read_ticketcache()['csrf']
+            self.ticket = self.read_ticketcache()['ticket']
+
+    def check_cacheexpire(self):
+        """
+        Checks if API ticket is expired.
+        Proxmox says ticket is valid for 2 hours. For safety we use 1 hour
+        :return: Boolean value of True if ticket is considered expired. False if opposite.
+        """
+        with open(CACHEFILE, 'r') as f:
+            data = json.load(f)
+            timestamp = data['timestamp']
+            return True if time.time() - timestamp > 3600 else False
+
+
+    def write_ticketcache(self):
+        """
+        Function writes API login ticket cache to tmp
+        """
+        data = {}
+        data['csrf'] = self.csrftoken
+        data['ticket'] = self.ticket
+        data['timestamp'] = time.time()
+        with open(CACHEFILE, 'w') as f:
+            json.dump(data, f)
+
+    def read_ticketcache(self):
+        """
+        Reads API login ticket cache file
+        :return: returns json parsed dict
+        """
+        with open(CACHEFILE, 'r') as f:
+            data = json.load(f)
+            return data
+
 
     def get_request(self, url):
         """