ovirt: fetch instance ip address from rest-api

This patch adds the support for returning the ip address of the instances
when reported by the guest-agent and from the rest-api.

Signed-off-by: Federico Simoncelli <fsimonce@redhat.com>

pkg/cloudprovider/ovirt/ovirt.go

@@ -25,6 +25,7 @@ import (
 	"net/http"
 	"net/url"
 	"path"
+	"sort"
 	"strings"
 
 	"code.google.com/p/gcfg"
@@ -32,6 +33,13 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/cloudprovider"
 )
 
+type OVirtInstance struct {
+	Name      string
+	IPAddress string
+}
+
+type OVirtInstanceMap map[string]OVirtInstance
+
 type OVirtCloud struct {
 	VmsRequest   *url.URL
 	HostsRequest *url.URL
@@ -48,9 +56,15 @@ type OVirtApiConfig struct {
 	}
 }
 
+type XmlVmAddress struct {
+	Address string `xml:"address,attr"`
+}
+
 type XmlVmInfo struct {
-	Hostname string `xml:"guest_info>fqdn"`
-	State    string `xml:"status>state"`
+	Name      string         `xml:"name"`
+	Hostname  string         `xml:"guest_info>fqdn"`
+	Addresses []XmlVmAddress `xml:"guest_info>ips>ip"`
+	State     string         `xml:"status>state"`
 }
 
 type XmlVmsList struct {
@@ -115,16 +129,31 @@ func (v *OVirtCloud) Zones() (cloudprovider.Zones, bool) {
 }
 
 // IPAddress returns the address of a particular machine instance
-func (v *OVirtCloud) IPAddress(instance string) (net.IP, error) {
-	// since the instance now is the IP in the ovirt env, this is trivial no-op
-	ip, err := net.LookupIP(instance)
-	if err != nil || len(ip) < 1 {
-		return nil, fmt.Errorf("cannot find ip address for: %s", instance)
+func (v *OVirtCloud) IPAddress(name string) (net.IP, error) {
+	instance, err := v.fetchInstance(name)
+	if err != nil {
+		return nil, err
 	}
-	return ip[0], nil
+
+	var address net.IP
+
+	if instance.IPAddress != "" {
+		address = net.ParseIP(instance.IPAddress)
+		if address == nil {
+			return nil, fmt.Errorf("couldn't parse address: %s", instance.IPAddress)
+		}
+	} else {
+		resolved, err := net.LookupIP(name)
+		if err != nil || len(resolved) < 1 {
+			return nil, fmt.Errorf("couldn't lookup address: %s", name)
+		}
+		address = resolved[0]
+	}
+
+	return address, nil
 }
 
-func getInstancesFromXml(body io.Reader) ([]string, error) {
+func getInstancesFromXml(body io.Reader) (OVirtInstanceMap, error) {
 	if body == nil {
 		return nil, fmt.Errorf("ovirt rest-api response body is missing")
 	}
@@ -140,20 +169,27 @@ func getInstancesFromXml(body io.Reader) ([]string, error) {
 		return nil, err
 	}
 
-	var instances []string
+	instances := make(OVirtInstanceMap)
 
 	for _, vm := range vmlist.Vm {
 		// Always return only vms that are up and running
 		if vm.Hostname != "" && strings.ToLower(vm.State) == "up" {
-			instances = append(instances, vm.Hostname)
+			address := ""
+			if len(vm.Addresses) > 0 {
+				address = vm.Addresses[0].Address
+			}
+
+			instances[vm.Hostname] = OVirtInstance{
+				Name:      vm.Name,
+				IPAddress: address,
+			}
 		}
 	}
 
 	return instances, nil
 }
 
-// List enumerates the set of minions instances known by the cloud provider
-func (v *OVirtCloud) List(filter string) ([]string, error) {
+func (v *OVirtCloud) fetchAllInstances() (OVirtInstanceMap, error) {
 	response, err := http.Get(v.VmsRequest.String())
 	if err != nil {
 		return nil, err
@@ -164,6 +200,41 @@ func (v *OVirtCloud) List(filter string) ([]string, error) {
 	return getInstancesFromXml(response.Body)
 }
 
+func (v *OVirtCloud) fetchInstance(name string) (*OVirtInstance, error) {
+	allInstances, err := v.fetchAllInstances()
+	if err != nil {
+		return nil, err
+	}
+
+	instance, found := allInstances[name]
+	if !found {
+		return nil, fmt.Errorf("cannot find instance: %s", name)
+	}
+
+	return &instance, nil
+}
+
+func (m *OVirtInstanceMap) ListSortedNames() []string {
+	var names []string
+
+	for k := range *m {
+		names = append(names, k)
+	}
+
+	sort.Strings(names)
+
+	return names
+}
+
+// List enumerates the set of minions instances known by the cloud provider
+func (v *OVirtCloud) List(filter string) ([]string, error) {
+	instances, err := v.fetchAllInstances()
+	if err != nil {
+		return nil, err
+	}
+	return instances.ListSortedNames(), nil
+}
+
 func (v *OVirtCloud) GetNodeResources(name string) (*api.NodeResources, error) {
 	return nil, nil
 }

pkg/cloudprovider/ovirt/ovirt_test.go

@@ -118,7 +118,9 @@ func TestOVirtCloudXmlParsing(t *testing.T) {
 	if len(instances4) != 2 {
 		t.Fatalf("Unexpected number of instance(s): %d", len(instances4))
 	}
-	if instances4[0] != "host1" || instances4[1] != "host3" {
+
+	names := instances4.ListSortedNames()
+	if names[0] != "host1" || names[1] != "host3" {
 		t.Fatalf("Unexpected instance(s): %s", instances4)
 	}
 }