lxctest

Overview

lxctest provides a wrapper around lxd-client tools to automate test execution, while leaving the test creation and analysis to the user. It uses LXC to launch Ubuntu containers with specific customizations, run a series of commands, and items to gather as output all set by the user. By using LXC the user has a much faster way of running tests compared to VMs.

Running lxctest

Distribution Dependencies

sudo apt install lxd distro-info python3-pip python3-yaml

Install via PyPI

pip3 install lxctest
lxctest <filename>

Install via git

git clone https://github.com/powersj/lxctest
cd lxctest
pip3 install -r requirements.txt
python3 -m lxctest <filename>

YAML Format

A single YAML test case file is used to define the following items for each test:

• Image Specification
• Image Customization
• Command Execution
• File Collection

The syntax for each of the above is defined below.

Image Specification

The image specification defines what LXC image will be used for the test. This includes the store and release. If no options are received, then by default the release LTS image will be used. Specifically:

lxc:
  store: release
  releases: lts

Store

Defines which store of Ubuntu images to use. Two options:

• images: standard images, see lxc image list images: for a full list. This is the default option.
• ubuntu: Images containing cloud-init, see lxc image list ubuntu: for a full list.
• ubuntu-daily: Daily images containing cloud-init, see lxc image list ubuntu-daily: for a full list.

lxc:
  store: images  # Default
  store: ubuntu
  store: ubuntu-daily

Release

Defines the targeted releases from the following options:

• lts: Use the current Ubuntu LTS, see ubuntu-distro-info --lts. This is the default option.
• supported: Run across all supported Ubuntu versions, see ubuntu-distro-info --supported.
• Specify a specific collection of releases. If one of the releases does not exist then no tests will run.

lxc:
  releases: lts  # Default
  releases: supported
  releases:
    - xenial
    - yakkety
    - fedora/22

Architecture

Architecture to test is defined by the system's architecture.

Image Customization

There are two possible ways to customize an image: 1) push specific files to a container 2) use cloud-init's user-data to inject data.

Push Files

Files can be pushed over using lxc file push to customize the container. This is done via a list of lists specifying the source and then destination.

push:
  - - my_local_script.sh
    - /usr/bin/
  - - examples/scripts/test.py
    - /root/

User-Data

If the image used contains cloud-init, then user-data can be passed to the container. This is done using a file containing the cloud data. This data is passed in via --config=user.user-data= option on container launch.

user-data: my_data.txt

Command Execution

Runs lxc exec on a list of commands to execute once the container is up and running.

execute:
  - python my_script.py
execute:
  - whoami
  - date
  - uname -a

File Collection

Files can be pulled using lxc file pull to collect information or results from the container. Only the source is required as all files will be put in the log directory.

pull:
  - file
pull:
  - file1
  - file2