Add config file support

pvcd.py

@@ -23,44 +23,62 @@
 import kazoo.client
 import libvirt
 import sys
+import os
 import socket
 import uuid
 import VMInstance
 import NodeInstance
 import time
 import atexit
+import configparser
 import apscheduler.schedulers.background
+import fencenode
 import ansiiprint
 
-def help():
-    print(ansiiprint.bold() + "pvcd - Parallel Virtual Cluster management daemon" + ansiiprint.end())
-#    exit(0)
+print(ansiiprint.bold() + "pvcd - Parallel Virtual Cluster management daemon" + ansiiprint.end())
 
-help()
+# Get the config file variable from the environment
+try:
+    pvcd_config_file = os.environ['PVC_CONFIG_FILE']
+except:
+    print('ERROR: The "PVC_CONFIG_FILE" environment variable must be set before starting pvcd.')
+    exit(1)
+
+print('Loading configuration from file {}'.format(pvcd_config_file))
+
+def readConfig(pvcd_config_file, myhostname):
+    o_config = configparser.ConfigParser()
+    o_config.read(pvcd_config_file)
+    entries = o_config[myhostname]
+    config = {}
+    for entry in entries:
+        config[entry] = entries[entry]
+    return config
+
+myhostname = socket.gethostname()
+config = readConfig(pvcd_config_file, myhostname)
 
 # Connect to local zookeeper
-zk = kazoo.client.KazooClient(hosts='127.0.0.1:2181')
+zk = kazoo.client.KazooClient(hosts=config['zookeeper'])
 try:
+    print('Connecting to Zookeeper instance at {}'.format(config['zookeeper']))
     zk.start()
 except:
-    print(ansiiprint.red() + "Failed to connect to local Zookeeper instance" + ansiiprint.end())
+    print('ERROR: Failed to connect to Zookeeper')
     exit(1)
 
 def zk_listener(state):
     if state == kazoo.client.KazooState.LOST:
         cleanup()
-        exit(2)
+        exit(1)
     elif state == kazoo.client.KazooState.SUSPENDED:
         cleanup()
-        exit(2)
+        exit(1)
     else:
         pass
 
 zk.add_listener(zk_listener)
 
-myhostname = socket.gethostname()
-mynodestring = '/nodes/%s' % myhostname
-
 def cleanup():
     try:
         update_timer.shutdown()
@@ -80,12 +98,17 @@ else:
     print("Node is " + ansiiprint.red() + "absent" + ansiiprint.end() + " in Zookeeper; adding new node")
     keepalive_time = int(time.time())
     zk.create('/domains/{}'.format(myhostname), 'hypervisor'.encode('ascii'))
+    # Basic state information
     zk.create('/domains/{}/state'.format(myhostname), 'stop'.encode('ascii'))
     zk.create('/domains/{}/cpucount'.format(myhostname), '0'.encode('ascii'))
     zk.create('/domains/{}/memfree'.format(myhostname), '0'.encode('ascii'))
     zk.create('/domains/{}/cpuload'.format(myhostname), '0.0'.encode('ascii'))
     zk.create('/domains/{}/runningdomains'.format(myhostname), ''.encode('ascii'))
+    # Keepalives and fencing information
     zk.create('/domains/{}/keepalive'.format(myhostname), str(keepalive_time).encode('ascii'))
+    zk.create('/domains/{}/ipmiaddress'.format(myhostname), ''.encode('ascii'))
+    zk.create('/domains/{}/ipmiusername'.format(myhostname), ''.encode('ascii'))
+    zk.create('/domains/{}/ipmipassword'.format(myhostname), ''.encode('ascii'))
 
 t_node = dict()
 s_domain = dict()
@@ -101,7 +124,7 @@ def updatenodes(new_node_list):
         if node in t_node:
             t_node[node].updatenodelist(t_node)
         else:
-            t_node[node] = NodeInstance.NodeInstance(node, t_node, s_domain, zk)
+            t_node[node] = NodeInstance.NodeInstance(node, t_node, s_domain, zk, config)
 
 @zk.ChildrenWatch('/domains')
 def updatedomains(new_domain_list):
@@ -110,7 +133,7 @@ def updatedomains(new_domain_list):
     print(ansiiprint.blue() + 'Domain list: ' + ansiiprint.end() + '{}'.format(' '.join(domain_list)))
     for domain in domain_list:
         if not domain in s_domain:
-            s_domain[domain] = VMInstance.VMInstance(domain, zk, t_node[myhostname]);
+            s_domain[domain] = VMInstance.VMInstance(domain, zk, config, t_node[myhostname]);
             for node in node_list:
                 if node in t_node:
                     t_node[node].updatedomainlist(s_domain)
@@ -121,7 +144,7 @@ update_zookeeper = this_node.update_zookeeper
 
 # Create timer to update this node in Zookeeper
 update_timer = apscheduler.schedulers.background.BackgroundScheduler()
-update_timer.add_job(update_zookeeper, 'interval', seconds=5)
+update_timer.add_job(update_zookeeper, 'interval', seconds=config['keepalive_interval'])
 update_timer.start()
 
 # Tick loop