check if compute AZ is available

Before creating a machine in a given AZ, it'll check that the AZ
actually exists and is available.

JIRA: https://issues.redhat.com/browse/OSASINFRA-1848
Signed-off-by: Emilien Macchi <emilien@redhat.com>

pkg/cloud/openstack/clients/machineservice.go

@@ -49,6 +49,7 @@ import (
 	"github.com/gophercloud/gophercloud/openstack/networking/v2/subnets"
 	"github.com/gophercloud/gophercloud/pagination"
 	"github.com/gophercloud/utils/openstack/clientconfig"
+	azutils "github.com/gophercloud/utils/openstack/compute/v2/availabilityzones"
 	configclient "github.com/openshift/client-go/config/clientset/versioned/typed/config/v1"
 	machinev1 "github.com/openshift/machine-api-operator/pkg/apis/machine/v1beta1"
 	"github.com/openshift/machine-api-operator/pkg/util"
@@ -915,6 +916,23 @@ func (is *InstanceService) DoesImageExist(imageName string) error {
 	return nil
 }
 
+// DoesAvailabilityZoneExist return an error if AZ with the given name doesn't exist, and nil otherwise
+func (is *InstanceService) DoesAvailabilityZoneExist(azName string) error {
+	zones, err := azutils.ListAvailableAvailabilityZones(is.computeClient)
+	if err != nil {
+		return err
+	}
+	if len(zones) == 0 {
+		return fmt.Errorf("could not find an available compute availability zone")
+	}
+	for _, zoneName := range zones {
+		if zoneName == azName {
+			return nil
+		}
+	}
+	return fmt.Errorf("could not find compute availability zone: %s", azName)
+}
+
 func (is *InstanceService) GetInstance(resourceId string) (instance *Instance, err error) {
 	if resourceId == "" {
 		return nil, fmt.Errorf("ResourceId should be specified to  get detail.")

pkg/cloud/openstack/machine/actuator.go

@@ -711,5 +711,11 @@ func (oc *OpenstackClient) validateMachine(machine *machinev1.Machine) error {
 		return err
 	}
 
+	// Validate that Availability Zone exists
+	err = machineService.DoesAvailabilityZoneExist(machineSpec.AvailabilityZone)
+	if err != nil {
+		return err
+	}
+
 	return nil
 }

vendor/modules.txt

@@ -97,6 +97,7 @@ github.com/gophercloud/gophercloud/openstack
 github.com/gophercloud/gophercloud/openstack/blockstorage/v3/volumes
 github.com/gophercloud/gophercloud/openstack/common/extensions
 github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/attachinterfaces
+github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/availabilityzones
 github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/bootfromvolume
 github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/floatingips
 github.com/gophercloud/gophercloud/openstack/compute/v2/extensions/keypairs
@@ -126,6 +127,7 @@ github.com/gophercloud/utils/env
 github.com/gophercloud/utils/gnocchi
 github.com/gophercloud/utils/internal
 github.com/gophercloud/utils/openstack/clientconfig
+github.com/gophercloud/utils/openstack/compute/v2/availabilityzones
 # github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7
 github.com/gregjones/httpcache
 github.com/gregjones/httpcache/diskcache