Using Hooks

This chapter explains how to extend the LISA software with a new hook.

A hook is a mechanism that allows for the automatic inclusion of test setup or teardown logic for all the tests running in LISA. An alternate definition of a hook is a system-wide companion.

Hooks are used as follows:

To configure test environments.
To prevent tests that are not properly configured or do not follow defined best practices from executing.
To provide common operations.

Anything that a hook can perform can also be modeled as a companion in LISA. However, there are several differences between hooks and companions:

Hooks are global in scope. Users do not specifically include a hook in their test case as is the required practice for companions. If you need every test to include the logic and want to prevent users from accidentally not including it, a hook is preferable.
Companions can have custom parameters and are rendered in the model editor. Hooks are practically invisible to the user and therefore can request no special parameters. Hooks get their parameters from properties in the configuration or from the system.
Hooks are deployed at the LISA install level, not at the test case level. Assume a test is run on two computers. One computer has a hook that is registered, and the other does not. The hook runs only when the test is staged on the computer where it is explicitly deployed. The defined companions execute regardless of any install-level configuration.

This section contains the following topics:

Create a New Hook

Deploy a New Hook