Tempest Run Command

Tempest Run Command

https://blueprints.launchpad.net/tempest/+spec/tempest-run-cmd

Describes a domain-specific tempest run command to be used as the primary entry point for running Tempest tests.

Problem Description

There are a wide range of Tempest use cases ranging from OpenStack gate testing to the testing of existing public and private clouds across multiple environments and configurations. Each of these user scenarios has its own requirements and challenges.

Currently, tempest doesn’t actually control it’s own execution. It instead relies on an external test runner, it does not provide a consistent experience for consumers of Tempest. Users also often have impression that tempest controls it’s own execution. In addition, because these test runners are in no way specific to Tempest any, items that are domain specific (such as configuration) must be performed out-of-band using shell scripts or other means.

Proposed Change

Since an effort is already underway to create a set of Tempest-specific command line tooling, this spec further defines a tempest run command. This spec addresses the following problems:

  • Providing a flexible runner that enables multiple approaches to the test discovery and execution processes
  • Facilitating ease of configuration and execution of Tempest across multiple environments and configurations
  • Builds on testrepository directly in order to leverage current and future testrepository capabilities

This spec outlines the beginning steps and basic functionality of the initial implementation of the run command. It is expected that the functionality of run will grow over time to suit the needs of tempest in the future.

The command implementation can be broken down into three components:

  • Converting the selection regex logic from ostestr into a reusable module
  • A command line interface that users will interact with
  • A client that drives the execution of tests by interfacing directly with testrepository

The logical flow of the proposed test runner is as follows:

  • Parse any command line arguments.
  • Set necessary environment variables for Tempest based on inputs.
  • Determine the set of tests to run using ostestr regex builder
  • Call into testrepository with the testr-specific arguments
  • Receive the results from test execution
  • Perform any post-processing on the test results, if applicable.

Command Line Interface

The list of proposed command line arguments are as follows:

Test Execution:

--parallel
--serial
--workers <workers>
--list

Test Selection and Discovery:

--tags <list of tag name>
--services <list of services>

--include <regex>
--whitelist-file <file name>
--exclude <regex>
--blacklist-file <file name>
  Sample regex file:

      (^tempest\.api) # Comments about this regex
      tempest.scenario.test_server_basic_ops # Matches this test explicitly

Aliases for most commonly used regexes:

--smoke
--all

By default the regex will run the equivalent of the full jobs in tox. (running everything but tests tagged as slow)

Output:

--subunit
--html <file name>

By default the console output will be output from subunit-trace

Tempest Configuration:

--config <config file>

Part of having tempest run having domain specific knowledge is that it’s aware of tempest workspaces and when running in it. However, workspaces aren’t a requirement for actually running tempest, and there is are existing workflows where you have a separate tempest config file. (which previously could only be specified by environment variables) This option is providing an easier to use place on the CLI for doing this. This is a key advantage of having tempest own it’s runner is that it provides another place for passing this type of information into tempest which we previously could only do via env vars or the config file.

Testrepository Integration

One of the goals of this spec is to develop an entry point from Tempest that integrates directly with testrepository rather than calling out to testr via subprocess. This integration is a more robust design that allows new features in testrepository to propagate more easily to the Tempest runner. Inversely, as the Tempest runner evolves, features that would be useful to any test runner can be pushed down the stack into testrepository.

The planned integration point of the tempest run command with testrepository is the CLI UI for testr. However, this only one possible approach. The final solution is likely to evolve during development.

Projects

  • openstack/tempest

Implementation

  • Extract the regex building logic from ostestr into an externally consumable module
  • Create a tempest run entry point in Tempest using cliff
  • Handle setup of Tempest specific options such as Tempest configuration
  • Implement test selection logic using the ostestr bits and based on the provided filtering options (regexes, tags, etc.)

Assignee(s)

Primary assignee: - mtreinish - slowrie

Milestones

Target Milestone for completion:
Newton-2
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