Make add/updateHost a bit more resilient

* provide a updateOrAddHost method that first will try to update an
  existing one, before adding a host entry

2 files changed, 13 insertions, 4 deletions

diff --git a/libvirt/resource_libvirt_domain.go b/libvirt/resource_libvirt_domain.go
index 95a7b7fe..ffbdc40b 100644
--- a/libvirt/resource_libvirt_domain.go
+++ b/libvirt/resource_libvirt_domain.go
@@ -587,9 +587,9 @@ func resourceLibvirtDomainCreate(d *schema.ResourceData, meta interface{}) error
 					if ip == nil {
 						return fmt.Errorf("Could not parse addresses '%s'", address)
 					}
-					// TODO: we should check the IP is contained in the DHCP addresses served
+
 					log.Printf("[INFO] Adding IP/MAC/host=%s/%s/%s to %s", ip.String(), mac, hostname, networkName)
-					if err := addHost(network, ip.String(), mac, hostname); err != nil {
+					if err := updateOrAddHost(network, ip.String(), mac, hostname); err != nil {
 						return err
 					}
 				}
@@ -720,7 +720,7 @@ func resourceLibvirtDomainCreate(d *schema.ResourceData, meta interface{}) error
 			for _, addressI := range addressesI.([]interface{}) {
 				address := addressI.(string)
 				log.Printf("[INFO] Finally adding IP/MAC/host=%s/%s/%s", address, mac, pending.hostname)
-				addHost(pending.network, address, mac, pending.hostname)
+				updateOrAddHost(pending.network, address, mac, pending.hostname)
 				if err != nil {
 					return fmt.Errorf("Could not add IP/MAC/host=%s/%s/%s: %s", address, mac, pending.hostname, err)
 				}
@@ -818,7 +818,7 @@ func resourceLibvirtDomainUpdate(d *schema.ResourceData, meta interface{}) error
 					return fmt.Errorf("Could not parse addresses '%s'", address)
 				}
 				log.Printf("[INFO] Updating IP/MAC/host=%s/%s/%s in '%s' network", ip.String(), mac, hostname, networkName)
-				if err := updateHost(network, ip.String(), mac, hostname); err != nil {
+				if err := updateOrAddHost(network, ip.String(), mac, hostname); err != nil {
 					return err
 				}
 			}
diff --git a/libvirt/utils_libvirt.go b/libvirt/utils_libvirt.go
index 22816769..0b1da1ef 100644
--- a/libvirt/utils_libvirt.go
+++ b/libvirt/utils_libvirt.go
@@ -46,6 +46,15 @@ func updateHost(n *libvirt.Network, ip, mac, name string) error {
 	return n.Update(libvirt.NETWORK_UPDATE_COMMAND_MODIFY, libvirt.NETWORK_SECTION_IP_DHCP_HOST, -1, xmlDesc, libvirt.NETWORK_UPDATE_AFFECT_CURRENT)
 }
 
+// Tries to update first, if that fails, it will add it
+func updateOrAddHost(n *libvirt.Network, ip, mac, name string) error {
+	err := updateHost(n, ip, mac, name)
+	if virErr, ok := err.(libvirt.Error); ok && virErr.Code == libvirt.ERR_OPERATION_INVALID && virErr.Domain == libvirt.FROM_NETWORK {
+		return addHost(n, ip, mac, name)
+	}
+	return err
+}
+
 func getHostArchitecture(virConn *libvirt.Connect) (string, error) {
 	type HostCapabilities struct {
 		XMLName xml.Name `xml:"capabilities"`