Merge pull request #55393 from jamiehannaford/octavia

Automatic merge from submit-queue (batch tested with PRs 55868, 55393, 55152, 55849). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Adds Octavia v2 as LoadBalancer provider

**What this PR does / why we need it**:

Adds support for using Octavia as the OpenStack LB provider.  

**Which issue(s) this PR fixes**:

Although some LB providers can be specified using the [lb-provider](https://github.com/kubernetes/kubernetes/pull/54176/files#diff-694c675fe77b09923cc453e7228f8fa8R85) JSON request field, other installations which use Octavia by default rely on it being discovered via the service catalog. When a user specifies the `load-balancer` service type, it will get back the root Octavia endpoint URL, which needs to have `v2.0` appended to it.

To facilitate this change, gophercloud recently added the `NewLoadBalancerV2` helper in gophercloud/gophercloud#591.

**Release note**:

```release-note
Octavia v2 now supported as a LB provider
```

/cc @xgerman

Author: Kubernetes Submit Queue

pkg/cloudprovider/providers/openstack/openstack.go

@@ -74,11 +74,13 @@ func (d *MyDuration) UnmarshalText(text []byte) error {
 type LoadBalancer struct {
 	network *gophercloud.ServiceClient
 	compute *gophercloud.ServiceClient
+	lb      *gophercloud.ServiceClient
 	opts    LoadBalancerOpts
 }
 
 type LoadBalancerOpts struct {
 	LBVersion            string     `gcfg:"lb-version"`          // overrides autodetection. Only support v2.
+	UseOctavia           bool       `gcfg:"use-octavia"`         // uses Octavia V2 service catalog endpoint
 	SubnetId             string     `gcfg:"subnet-id"`           // overrides autodetection.
 	FloatingNetworkId    string     `gcfg:"floating-network-id"` // If specified, will create floating ip for loadbalancer, or do not create floating ip.
 	LBMethod             string     `gcfg:"lb-method"`           // default to ROUND_ROBIN.
@@ -507,6 +509,11 @@ func (os *OpenStack) LoadBalancer() (cloudprovider.LoadBalancer, bool) {
 		return nil, false
 	}
 
+	lb, err := os.NewLoadBalancerV2()
+	if err != nil {
+		return nil, false
+	}
+
 	// LBaaS v1 is deprecated in the OpenStack Liberty release.
 	// Currently kubernetes OpenStack cloud provider just support LBaaS v2.
 	lbVersion := os.lbOpts.LBVersion
@@ -517,7 +524,7 @@ func (os *OpenStack) LoadBalancer() (cloudprovider.LoadBalancer, bool) {
 
 	glog.V(1).Info("Claiming to support LoadBalancer")
 
-	return &LbaasV2{LoadBalancer{network, compute, os.lbOpts}}, true
+	return &LbaasV2{LoadBalancer{network, compute, lb, os.lbOpts}}, true
 }
 
 func isNotFound(err error) bool {

pkg/cloudprovider/providers/openstack/openstack_client.go

@@ -62,3 +62,21 @@ func (os *OpenStack) NewBlockStorageV2() (*gophercloud.ServiceClient, error) {
 	}
 	return storage, nil
 }
+
+func (os *OpenStack) NewLoadBalancerV2() (*gophercloud.ServiceClient, error) {
+	var lb *gophercloud.ServiceClient
+	var err error
+	if os.lbOpts.UseOctavia {
+		lb, err = openstack.NewLoadBalancerV2(os.provider, gophercloud.EndpointOpts{
+			Region: os.region,
+		})
+	} else {
+		lb, err = openstack.NewNetworkV2(os.provider, gophercloud.EndpointOpts{
+			Region: os.region,
+		})
+	}
+	if err != nil {
+		return nil, fmt.Errorf("failed to find load-balancer v2 endpoint for region %s: %v", os.region, err)
+	}
+	return lb, nil
+}