README.md

Tekton Lint custom rules

• Create a regular node module
• Default export from this of an object

module.exports = {
    rules: [
        {
            name: 'no-tasks-called-task',
            reportDefault: 'error',
            ruleFn: forbidTasksWithTaskInTheName
        }
    ]
}

- Must contain a field called `rules` that is a array of objects
- Each 'rule' object, must hava name (kebab case preferred)
- Default report type (off/error/warning)
- Reference to the rules function

• Rules are implemented in a function

// Example rule to check a name of a task, note this isn't meant
// to be a serious rule - rather as an example
const forbidTasksWithTaskInTheName = (docs, tekton, report) => {

    // try to always code defensively
    if (tekton.tasks) {
        for (const t of Object.values(tekton.tasks)) {
            if (t.metadata.name.startsWith("Task")) {
                report("Tasks should not start with word 'Task'", t)
            }
        }
    }
};

- `docs` are the full yaml docs
- `tekton` is the object with the parsed elements of the yaml files
- `report` is a fn to report rule breaks

Development Notes:

• As well as the yaml files from the project being tested, the rule will also see the cached elements
• try and code as defensively as possible, eg a set of files might not have Tasks