feat(loadbalancer): add load balancer resize

openstack/loadbalancer/v2/loadbalancers/doc.go

@@ -136,5 +136,17 @@ Example to Failover a Load Balancers
 	if err != nil {
 		panic(err)
 	}
+
+Example to Resize a Load Balancer (OVHcloud Octavia only)
+
+	lbID := "d67d56a6-4a86-4688-a282-f46444705c64"
+	resizeOpts := loadbalancers.ResizeOpts{
+		NewFlavorID: "bba40eb2-ee8c-11e9-81b4-2a2ae2dbcce4",
+	}
+
+	err := loadbalancers.Resize(context.TODO(), networkClient, lbID, resizeOpts).ExtractErr()
+	if err != nil {
+		panic(err)
+	}
 */
 package loadbalancers

openstack/loadbalancer/v2/loadbalancers/requests.go

@@ -279,3 +279,38 @@ func Failover(ctx context.Context, c *gophercloud.ServiceClient, id string) (r F
 	_, r.Header, r.Err = gophercloud.ParseResponse(resp, err)
 	return
 }
+
+// ResizeOptsBuilder allows extensions to add additional parameters to the
+// Resize request.
+type ResizeOptsBuilder interface {
+	ToLoadBalancerResizeMap() (map[string]any, error)
+}
+
+// ResizeOpts is the common options struct used in this package's Resize
+// operation.
+type ResizeOpts struct {
+	// The ID of the flavor to resize the load balancer to.
+	NewFlavorID string `json:"new_flavor_id" required:"true"`
+}
+
+// ToLoadBalancerResizeMap builds a request body from ResizeOpts.
+func (opts ResizeOpts) ToLoadBalancerResizeMap() (map[string]any, error) {
+	return gophercloud.BuildRequestBody(opts, "")
+}
+
+// Resize changes the flavor of a load balancer: Octavia fails it over onto
+// amphorae of the new flavor. This call is not part of upstream Octavia; it
+// is OVHcloud's downstream patch (upstream change 890215, spec "Load balancer
+// resizing").
+func Resize(ctx context.Context, c *gophercloud.ServiceClient, id string, opts ResizeOptsBuilder) (r ResizeResult) {
+	b, err := opts.ToLoadBalancerResizeMap()
+	if err != nil {
+		r.Err = err
+		return
+	}
+	resp, err := c.Put(ctx, resizeRootURL(c, id), b, nil, &gophercloud.RequestOpts{
+		OkCodes: []int{202},
+	})
+	_, r.Header, r.Err = gophercloud.ParseResponse(resp, err)
+	return
+}

openstack/loadbalancer/v2/loadbalancers/results.go

@@ -264,3 +264,9 @@ type DeleteResult struct {
 type FailoverResult struct {
 	gophercloud.ErrResult
 }
+
+// ResizeResult represents the result of a resize operation. Call its
+// ExtractErr method to determine if the request succeeded or failed.
+type ResizeResult struct {
+	gophercloud.ErrResult
+}

openstack/loadbalancer/v2/loadbalancers/testing/fixtures_test.go

@@ -633,3 +633,14 @@ func HandleLoadbalancerFailoverSuccessfully(t *testing.T, fakeServer th.FakeServ
 		w.WriteHeader(http.StatusAccepted)
 	})
 }
+
+// HandleLoadbalancerResizeSuccessfully sets up the test server to respond to a loadbalancer resize request.
+func HandleLoadbalancerResizeSuccessfully(t *testing.T, fakeServer th.FakeServer) {
+	fakeServer.Mux.HandleFunc("/v2.0/lbaas/loadbalancers/36e08a3e-a78f-4b40-a229-1e7e23eee1ab/resize", func(w http.ResponseWriter, r *http.Request) {
+		th.TestMethod(t, r, "PUT")
+		th.TestHeader(t, r, "X-Auth-Token", client.TokenID)
+		th.TestJSONRequest(t, r, `{"new_flavor_id": "bba40eb2-ee8c-11e9-81b4-2a2ae2dbcce4"}`)
+
+		w.WriteHeader(http.StatusAccepted)
+	})
+}

openstack/loadbalancer/v2/loadbalancers/testing/requests_test.go

@@ -239,3 +239,21 @@ func TestFailoverLoadbalancer(t *testing.T) {
 	res := loadbalancers.Failover(context.TODO(), fake.ServiceClient(fakeServer), "36e08a3e-a78f-4b40-a229-1e7e23eee1ab")
 	th.AssertNoErr(t, res.Err)
 }
+
+func TestResizeLoadbalancer(t *testing.T) {
+	fakeServer := th.SetupHTTP()
+	defer fakeServer.Teardown()
+	HandleLoadbalancerResizeSuccessfully(t, fakeServer)
+
+	res := loadbalancers.Resize(context.TODO(), fake.ServiceClient(fakeServer), "36e08a3e-a78f-4b40-a229-1e7e23eee1ab", loadbalancers.ResizeOpts{
+		NewFlavorID: "bba40eb2-ee8c-11e9-81b4-2a2ae2dbcce4",
+	})
+	th.AssertNoErr(t, res.Err)
+}
+
+func TestResizeLoadbalancerRequiresAFlavor(t *testing.T) {
+	res := loadbalancers.Resize(context.TODO(), nil, "36e08a3e-a78f-4b40-a229-1e7e23eee1ab", loadbalancers.ResizeOpts{})
+	if res.Err == nil {
+		t.Fatal("expected an error without new_flavor_id")
+	}
+}

openstack/loadbalancer/v2/loadbalancers/urls.go

@@ -8,6 +8,7 @@ const (
 	statusPath     = "status"
 	statisticsPath = "stats"
 	failoverPath   = "failover"
+	resizePath     = "resize"
 )
 
 func rootURL(c *gophercloud.ServiceClient) string {
@@ -29,3 +30,7 @@ func statisticsRootURL(c *gophercloud.ServiceClient, id string) string {
 func failoverRootURL(c *gophercloud.ServiceClient, id string) string {
 	return c.ServiceURL(rootPath, resourcePath, id, failoverPath)
 }
+
+func resizeRootURL(c *gophercloud.ServiceClient, id string) string {
+	return c.ServiceURL(rootPath, resourcePath, id, resizePath)
+}