cyclades: Add method to get ip stats to network

Extend Network model with a method to get the number of free and total
IPv4 addresses of the network. Also, add method to IPAddress model to
release its IPv4 address if any. Finally, update backend-list management
command to use 'ip_count' method of Network object.

snf-cyclades-app/synnefo/db/models.py

@@ -568,6 +568,17 @@ class Network(models.Model):
             if subnet.ipversion == version:
                 return subnet.cidr
 
+    def ip_count(self):
+        """Return the total and free IPv4 addresses of the network."""
+        subnets = self.subnets.filter(ipversion=4).prefetch_related("ip_pools")
+        total, free = 0, 0
+        for subnet in subnets:
+            for ip_pool in subnet.ip_pools.all():
+                pool = ip_pool.pool
+                total += pool.pool_size
+                free += pool.count_available()
+        return total, free
+
     class InvalidBackendIdError(Exception):
         def __init__(self, value):
             self.value = value
@@ -745,6 +756,15 @@ class IPAddress(models.Model):
     def public(self):
         return self.network.public
 
+    def release_address(self):
+        """Release the IPv4 address."""
+        if self.ipversion == 4:
+            for pool_row in self.subnet.ip_pools.all():
+                ip_pool = pool_row.pool
+                if ip_pool.contains(self.address):
+                    ip_pool.put(self.address)
+                    ip_pool.save()
+
 
 class NetworkInterface(models.Model):
     FIREWALL_PROFILES = (

snf-cyclades-app/synnefo/db/models_factory.py

@@ -242,7 +242,7 @@ class IPv6AddressFactory(IPv4AddressFactory):
 
 
 class FloatingIPFactory(IPv4AddressFactory):
-    network = factory.SubFactory(NetworkFactory, public=False,
+    network = factory.SubFactory(NetworkFactory, public=True,
                                  floating_ip_pool=True)
     floating_ip = True
 

snf-cyclades-app/synnefo/logic/management/commands/backend-list.py

@@ -53,9 +53,9 @@ class Command(ListCommand):
         free_ips = 0
         total_ips = 0
         for network in util.backend_public_networks(backend):
-            pool = network.get_pool(locked=False)
-            free_ips += pool.count_available()
-            total_ips += pool.pool_size
+            total, free = network.ip_count()
+            total_ips += total
+            free_ips += free
         return "%s/%s" % (free_ips, total_ips)
 
     FIELDS = {