Merge lp:~soren/nova/dnsmasq-leasesfile-init into lp:~hudson-openstack/nova/trunk

[Soren Hansen]

Make nova-dhcpbridge output lease information in dnsmasq's leasesfile format.

The output from nova-dhcpbridge has been wrong all along, but recently it caused dnsmasq to segfault. It's supposed to be in the format of dnsmasq's leases file, but it's currently in the format of dhcp-hosts.

[Josh Kearney (jk0)]

Looks great!

review: Approve

[Rick Harris (rconradharris)]

Think we could include a small test with this?

Other than that, looks great.

review: Approve

[Jay Pipes (jaypipes)]

lgtm.

review: Approve

[Devin Carlen (devcamcar)]

Agree with Rick. Let's add a test for this so we don't break it again in the future. :)

review: Needs Fixing

[lp:~soren/nova/dnsmasq-leasesfile-init]

763. By Soren Hansen on 2011-03-14

Add a unit test

[Soren Hansen (soren)]

Unit test added.

[lp:~soren/nova/dnsmasq-leasesfile-init]

764. By Soren Hansen on 2011-03-14

Merge trunk

[Devin Carlen (devcamcar)]

lgtm

review: Approve

=== modified file 'bin/nova-dhcpbridge'
--- bin/nova-dhcpbridge	2011-02-23 19:20:52 +0000
+++ bin/nova-dhcpbridge	2011-03-14 13:45:28 +0000
@@ -94,7 +94,7 @@
     """Get the list of hosts for an interface."""
     ctxt = context.get_admin_context()
     network_ref = db.network_get_by_bridge(ctxt, interface)
-    return linux_net.get_dhcp_hosts(ctxt, network_ref['id'])
+    return linux_net.get_dhcp_leases(ctxt, network_ref['id'])
 
 
 def main():

=== modified file 'nova/network/linux_net.py'
--- nova/network/linux_net.py	2011-03-11 02:44:01 +0000
+++ nova/network/linux_net.py	2011-03-14 13:45:28 +0000
@@ -19,6 +19,7 @@
 
 import inspect
 import os
+import calendar
 
 from eventlet import semaphore
 
@@ -56,6 +57,8 @@
                     'Public IP of network host')
 flags.DEFINE_string('input_chain', 'INPUT',
                     'chain to add nova_input to')
+flags.DEFINE_integer('dhcp_lease_time', 120,
+                     'Lifetime of a DHCP lease')
 
 flags.DEFINE_string('dns_server', None,
                     'if set, uses specific dns server for dnsmasq')
@@ -533,8 +536,17 @@
                                              bridge)
 
 
+def get_dhcp_leases(context, network_id):
+    """Return a network's hosts config in dnsmasq leasefile format"""
+    hosts = []
+    for fixed_ip_ref in db.network_get_associated_fixed_ips(context,
+                                                            network_id):
+        hosts.append(_host_lease(fixed_ip_ref))
+    return '\n'.join(hosts)
+
+
 def get_dhcp_hosts(context, network_id):
-    """Get a string containing a network's hosts config in dnsmasq format"""
+    """Get a string containing a network's hosts config in dhcp-host format"""
     hosts = []
     for fixed_ip_ref in db.network_get_associated_fixed_ips(context,
                                                             network_id):
@@ -625,8 +637,24 @@
                        utils.get_my_linklocal(network_ref['bridge'])})
 
 
+def _host_lease(fixed_ip_ref):
+    """Return a host string for an address in leasefile format"""
+    instance_ref = fixed_ip_ref['instance']
+    if instance_ref['updated_at']:
+        timestamp = instance_ref['updated_at']
+    else:
+        timestamp = instance_ref['created_at']
+
+    seconds_since_epoch = calendar.timegm(timestamp.utctimetuple())
+
+    return "%d %s %s %s *" % (seconds_since_epoch + FLAGS.dhcp_lease_time,
+                              instance_ref['mac_address'],
+                              fixed_ip_ref['address'],
+                              instance_ref['hostname'] or '*')
+
+
 def _host_dhcp(fixed_ip_ref):
-    """Return a host string for an address"""
+    """Return a host string for an address in dhcp-host format"""
     instance_ref = fixed_ip_ref['instance']
     return "%s,%s.%s,%s" % (instance_ref['mac_address'],
                                    instance_ref['hostname'],

=== modified file 'nova/tests/test_network.py'
--- nova/tests/test_network.py	2011-03-09 22:39:12 +0000
+++ nova/tests/test_network.py	2011-03-14 13:45:28 +0000
@@ -20,6 +20,7 @@
 """
 import IPy
 import os
+import time
 
 from nova import context
 from nova import db
@@ -463,6 +464,31 @@
                                                   network['id'])
         self.assertEqual(ip_count, num_available_ips)
 
+    def test_dhcp_lease_output(self):
+        admin_ctxt = context.get_admin_context()
+        address = self._create_address(0, self.instance_id)
+        lease_ip(address)
+        network_ref = db.network_get_by_instance(admin_ctxt, self.instance_id)
+        leases = linux_net.get_dhcp_leases(context.get_admin_context(),
+                                           network_ref['id'])
+        for line in leases.split('\n'):
+            seconds, mac, ip, hostname, client_id = line.split(' ')
+            self.assertTrue(int(seconds) > time.time(), 'Lease expires in '
+                                                        'the past')
+            octets = mac.split(':')
+            self.assertEqual(len(octets), 6, "Wrong number of octets "
+                                             "in %s" % (max,))
+            for octet in octets:
+                self.assertEqual(len(octet), 2, "Oddly sized octet: %s"
+                                                                    % (octet,))
+                # This will throw an exception if the octet is invalid
+                int(octet, 16)
+
+            # And this will raise an exception in case of an invalid IP
+            IPy.IP(ip)
+
+        release_ip(address)
+
 
 def is_allocated_in_project(address, project_id):
     """Returns true if address is in specified project"""