This utility provides a API to download/cache VM images (QCOW) from the official distributions repositories.

Basic Usage

Import vmimage module:

>>> from avocado.utils import vmimage

Get an image, which consists in an object with the path of the dowloaded/cached base image and the path of the external snapshot created out of that base image:

>>> image = vmimage.get()
>>> image
<Image name=Fedora version=26 arch=x86_64>
>>> image.name
>>> image.path
>>> image.get()
>>> image.path
>>> image.version
>>> image.base_image

If you provide more details about the image, the object is expected to reflect those details:

>>> image = vmimage.get(arch='aarch64')
>>> image
<Image name=FedoraSecondary version=26 arch=aarch64>
>>> image.name
>>> image.path

>>> image = vmimage.get(version=7)
>>> image
<Image name=CentOS version=7 arch=x86_64>
>>> image.path

Notice that, unlike the base_image attribute, the path attribute will be always different in each instance, as it actually points to an external snapshot created out of the base image:

>>> i1 = vmimage.get()
>>> i2 = vmimage.get()
>>> i1.path == i2.path

Custom Image Provider

If you need your own Image Provider, you can extend the vmimage.IMAGE_PROVIDERS list, including your provider class. For instance, using the vmimage utility in an Avocado test, we could add our own provider with:

from avocado import Test

from avocado.utils import vmimage

class MyProvider(vmimage.ImageProviderBase):

    name = 'MyDistro'

    def __init__(self, version='[0-9]+', build='[0-9]+.[0-9]+',
        :params version: The regular expression that represents
                         your distro version numbering.
        :params build: The regular expression that represents
                       your build version numbering.
        :params arch: The default architecture to look images for.
        super(MyProvider, self).__init__(version, build, arch)

        # The URL which contains a list of the distro versions
        self.url_versions = 'https://dl.fedoraproject.org/pub/fedora/linux/releases/'

        # The URL which contains a list of distro images
        self.url_images = self.url_versions + '{version}/CloudImages/{arch}/images/'

        # The images naming pattern
        self.image_pattern = 'Fedora-Cloud-Base-{version}-{build}.{arch}.qcow2$'

class MyTest(Test):

    def setUp(self):
        image = vmimage.get('MyDistro')

    def test(self):