Images (Glance)

If you are unfamiliar with an OpenStack image then you can think of it as a “virtual machine template”. Images can also be standard installation media such as ISO images.

Creating, Reserving and Uploading Images

If an image (template) is created without uploading the media then it is what is known as a reserved state. A reserved state means we have reserved a placeholder but it contains no image data (uploaded media). The status will be marked as Queued when in a reserve state. OpenStack4j will automatically change a create operation into a reserve operation if the image data/media is not defined.

Create and Upload an Image in a single call

To create and upload the image media in a single call see the example below:

// Create a Payload - we will use URL in this example
Payload<URL> payload = Payloads.create(new URL("https://some/url/cirros-0.3.0-x86_64-disk.img"));

Image image = os.images().create(Builders.image()
                .name("Cirros 0.3.0 x64")
                .isPublic(true)
                .containerFormat(ContainerFormat.BARE)
                .diskFormat(DiskFormat.QCOW2)
                .build()
                ), payload);

Reserve an Image

Image image = os.images().reserve(Builders.image()
                .name("Cirros 0.3.0 x64")
                .isPublic(true)
                .build());

Uploading Image Data

To upload image data/media see the examples below.

Uploading an Updating an image object already assigned

image = os.images().upload(image.getId(), 
                           Payloads.create(new File("/path/to/vmimage.img")), 
                           image.builder().containerFormat(ContainerFormat.BARE).diskFormat(DiskFormat.QCOW2));

Uploading only the image data without updating

os.images().upload("imageId", Payloads.create(new File("/path/to/vmimage.img"), null);

Updating, Deleting and Querying

Updating an Image

To update an image like changing it’s name or other template data see the example below.

os.images().update(image.toBuilder()
           .name("New VM Image Name").minDisk(1024).property("personal-distro", "true"));

Delete an Image

To permanently delete an image see the example below.

os.images().delete("imageId");

Querying for Images

// List all Images
List<? extends Image> images = os.images().list();
	
// Get an Image by ID
Image image = os.images().get("imageId");

Image Memberships

Image memberships are a way to share a private image with other tenants. Those tenants can also be assigned rights to re-share the private image. Public images are available but private images require memberships for non-owners to access.

Finding all Memberships for an Image

List<? extends ImageMember> members = os.images().listMembers("imageId");

Adding a Member (authorizing a tenant for a private image)

os.images().addMember("imageId", "tenantId");

Removing a Member (revoking a tenant)

os.images().removeMember("imageId", "tenantId");