blockstorage: add unmanage api call

Implemented missing blockstorage api call to unmanage volume.
ref. https://docs.openstack.org/api-ref/block-storage/v3/#unmanage-a-volume

Author: TOMOFUMI-KONDO

openstack/blockstorage/v3/volumes/doc.go

@@ -157,5 +157,12 @@ Example of Attaching a Volume to an Instance
 	if err != nil {
 		panic(err)
 	}
+
+Example of Unmanaging a Volume
+
+	err := volumes.Unmanage(context.TODO(), client, volume.ID).ExtractErr()
+	if err != nil {
+		panic(err)
+	}
 */
 package volumes

openstack/blockstorage/v3/volumes/requests.go

@@ -763,3 +763,14 @@ func ResetStatus(ctx context.Context, client *gophercloud.ServiceClient, id stri
 	_, r.Header, r.Err = gophercloud.ParseResponse(resp, err)
 	return
 }
+
+// Unmanage removes a volume from Block Storage management without
+// removing the back-end storage object that is associated with it.
+func Unmanage(ctx context.Context, client *gophercloud.ServiceClient, id string) (r UnmanageResult) {
+	body := map[string]any{"os-unmanage": make(map[string]any)}
+	resp, err := client.Post(ctx, actionURL(client, id), body, nil, &gophercloud.RequestOpts{
+		OkCodes: []int{202},
+	})
+	_, r.Header, r.Err = gophercloud.ParseResponse(resp, err)
+	return
+}

openstack/blockstorage/v3/volumes/results.go

@@ -399,3 +399,8 @@ type ReImageResult struct {
 type ResetStatusResult struct {
 	gophercloud.ErrResult
 }
+
+// UnmanageResult contains the response error from a Unmanage request.
+type UnmanageResult struct {
+	gophercloud.ErrResult
+}

openstack/blockstorage/v3/volumes/testing/fixtures_test.go

@@ -648,3 +648,19 @@ func MockResetStatusResponse(t *testing.T) {
 			w.WriteHeader(http.StatusAccepted)
 		})
 }
+
+func MockUnmanageResponse(t *testing.T) {
+	th.Mux.HandleFunc("/volumes/cd281d77-8217-4830-be95-9528227c105c/action",
+		func(w http.ResponseWriter, r *http.Request) {
+			th.TestMethod(t, r, "POST")
+			th.TestHeader(t, r, "X-Auth-Token", fake.TokenID)
+			th.TestHeader(t, r, "Content-Type", "application/json")
+			th.TestJSONRequest(t, r, `
+{
+	"os-unmanage": {}
+}
+			`)
+
+			w.WriteHeader(http.StatusAccepted)
+		})
+}

openstack/blockstorage/v3/volumes/testing/requests_test.go

@@ -538,3 +538,13 @@ func TestResetStatus(t *testing.T) {
 	err := volumes.ResetStatus(context.TODO(), client.ServiceClient(), "cd281d77-8217-4830-be95-9528227c105c", options).ExtractErr()
 	th.AssertNoErr(t, err)
 }
+
+func TestUnmanage(t *testing.T) {
+	th.SetupHTTP()
+	defer th.TeardownHTTP()
+
+	MockUnmanageResponse(t)
+
+	err := volumes.Unmanage(context.TODO(), client.ServiceClient(), "cd281d77-8217-4830-be95-9528227c105c").ExtractErr()
+	th.AssertNoErr(t, err)
+}