Writing a Validation Task

Writing a Validation Task

Similar to migration tasks, validation tasks are a specialized type of task that are use to ensure your project conforms to a set of requirements.

Some examples of validation tasks include

• ensuring your project has a group of related dependencies that match a minimum verison set
• validating whether your project is a valid ESM package
• ensuring that your project contains a valid set of configuration and packages for accessibility testing
• many more...

Validation tasks are a subclass of the BaseTask class, and have migration-specific methods and properties that make writing them easier. More details on what's included in this class can be found in the BaseValidationTask documentation.

A simple migration task

Below is a simple example of a validation task.

/tasks/my-validation-task.ts

import { BaseValidationTask, Task, TaskContext } from '@checkup/core';
import { Result } from 'sarif';

export default class MyValidationTask
  extends BaseValidationTask
  implements Task
{
  taskName = 'my-validation';
  taskDisplayName = 'My Validation';
  description = 'Validates a package';
  category = 'validation';

  constructor(pluginName: string, context: TaskContext) {
    super('My Validation', pluginName, context);

    this.addRuleComponentMetadata();

    this.addValidationStep('First step is valid', () => {
      return {
        isValid: validateFirstStep(),
      };
    });

    this.addValidationStep('Second step is valid', () => {
      return {
        isValid: validateSecondStep(),
      };
    });
  }

  async run(): Promise<Result[]> {
    let validationResults = await this.validate();

    // iterating the validation results and explicitly adding to the SARIF log
    // will allow consumers to add additional properties to the results
    for (let [messageText, validationResult] of validationResults) {
      this.addValidationResult(messageText, validationResult.isValid);
    }

    return this.results;
  }
}

/tasks/my-migration-task.js

const { BaseValidationTask, Task, TaskContext } = require('@checkup/core');

module.exports = class MyValidationTask extends BaseValidationTask {
  taskName = 'my-validation';
  taskDisplayName = 'My Validation';
  description = 'Validates a package';
  category = 'validation';

  constructor(pluginName, context) {
    super('My Validation', pluginName, context);

    this.addRuleComponentMetadata();

    this.addValidationStep('First step is valid', () => {
      return {
        isValid: validateFirstStep(),
      };
    });

    this.addValidationStep('Second step is valid', () => {
      return {
        isValid: validateSecondStep(),
      };
    });
  }

  async run() {
    let validationResults = await this.validate();

    // iterating the validation results and explicitly adding to the SARIF log
    // will allow consumers to add additional properties to the results
    for (let [messageText, validationResult] of validationResults) {
      this.addValidationResult(messageText, validationResult.isValid);
    }

    return this.results;
  }
};

Coupling this with the pretty formatter, we can get a full picture of the scope of our validation.

$ [yarn|npx] checkup run . --task my-validation --format pretty

Checkup report generated for checkup-app v1.3.0 (46 files analyzed)

This project is 100 days old, with 90 days active days, 375 commits and 46 files.

Checkup ran the following task(s) successfully:

My Validation
=================
Validation passed
  ✔ First step is valid
  ✔ Second step is valid