whitebox-tempest-plugin/README.rst

4.4 KiB

Whitebox Tempest plugin

This is a Tempest plugin for whitebox testing. While Tempest's scope is limited to only the REST APIs, whitebox allows tests to peak behind the curtain, similar to how a cloud admin might. Examining things on the compute host(s) and/or the controller(s) is not only allowed, it's required for a test to be in whitebox's scope. Whitebox tests must still be REST API-driven, however their assertions can involve things like the instance XML (if the Nova libvirt driver is in use) or the database.

Requirements

While Tempest is cloud-agnostic because all clouds expose the same OpenStack APIs (with some caveats around extensions), whitebox peaks behind the curtain, and thus is coupled to the way the cloud was deployed. Currently, devstack and TripleO (with undercloud and overcloud) are supported, with only devstack being tested in CI.

Some tests have specific hardware requirements. These should be documented as config options, and tests are expected to skip if their hardware requirements are not declared in the configuration.

Install, configure and run

  1. Tempest needs to be installed and configured.

  2. Install the plugin.

    This should be done from source. :

    WORKSPACE=/some/directory
    cd $WORKSPACE
    git clone https://opendev.org/openstack/whitebox-tempest-plugin
    
    sudo pip install whitebox-tempest-plugin
  3. Configure Tempest.

    The exact configuration will depend on the deployment. There is no configuration reference yet, have a look at whitebox_tempest_plugin/config.py instead. As an example, here is a configuration for a multinode TripleO deployment. :

    [whitebox]
    ctlplane_addresses = compute-0.localdomain:192.168.24.6,compute-1.localdomain:192.168.24.12
    ctlplane_ssh_username = heat-admin
    ctlplane_ssh_private_key_path = /home/stack/.ssh/id_rsa
    containers = true
    max_compute_nodes = 2 # Some tests depend on there being a single (available) compute node

    Here is an example for a two-node DevStack deployment:

    [whitebox]
    nodes_yaml = /opt/stack/whitebox-tempest-plugin/nodes.yaml
    ctlplane_ssh_username = vagrant
    ctlplane_ssh_private_key_path = /home/vagrant/.ssh/id_rsa

    with a nodes.yaml file that looks something like:

    controller:
      services:
        libvirt:
          start-command: 'systemctl start libvirtd'
          stop_command: 'systemctl stop libvirtd'
        nova-compute:
          config_path: '/etc/nova/nova-cpu.conf'
          start_command: 'systemctl start devstack@n-cpu'
          stop_command: 'systemctl stop devstack@n-cpu'
    compute1:
      services:
        libvirt:
          start-command: 'systemctl start libvirtd'
          stop_command: 'systemctl stop libvirtd'
        nova-compute:
          config_path: '/etc/nova/nova-cpu.conf'
          start_command: 'systemctl start devstack@n-cpu'
          stop_command: 'systemctl stop devstack@n-cpu'

    where controller is the hostname of the controller node and compute1 is the hostname of the second node running nova-compute.

  4. Execute the tests. :

    tempest run --serial --regex whitebox_tempest_plugin.

    Important

    Whitebox expects its tests to run one at a time. Make sure to pass --serial or --concurrency 1 to tempest run.

How to add a new test

Tests should fit whitebox's scope. If a test intereacts with REST APIs and nothing else, it is better suited for Tempest itself. New tests should be added in their respective subdirectories. For example, tests that use the compute API live in whitebox_tempest_plugin/api/compute. Test code does not need unit tests, but helpers or utilities do. Unit tests live in whitebox_tempest_plugin/tests. Whitebox does not adhere to the Tempest plugin interface <https://docs.openstack.org/tempest/latest/plugin.html>. As mentioned, whitebox tests run one at a time, so it's safe for a test to modify the environment and/or be destructive, as long as it cleans up after itself. For example, changing Nova configuration values and/or restarting services is acceptable, as long as the original values and service state are restored.