crictl Charm Installation

crictl_install.py

@when('config.changed.crictl-version')
def crictl_version_changed():
    """
    crictl version has changed.

    :return: None
    """
    remove_state('crictl.installed')


@when_not('crictl.installed')
def install_crictl():
    """
    Install the crictl binary.

    :return: None
    """
    cfg = hookenv.config()
    url = 'https://github.com/kubernetes-sigs/' \
          'cri-tools/releases/download/v{0}/' \
          'crictl-v{0}-linux-amd64.tar.gz'.format(
              cfg.get('crictl-version'))
    path = '/usr/bin/crictl'

    if os.path.isfile(path):
        os.remove(path)

    # Download the archive into memory and extract straight into /usr/bin/.
    with urlopen(url) as request:
        with BytesIO(request.read()) as download:
            with tarfile.open(fileobj=download, mode='r:gz') as tar:
                tar.extract(
                    os.path.basename(path),
                    os.path.dirname(path)
                )

    set_state('crictl.installed')