Marble seeds Tasks module

Install with

npm i @marble-seeds/@marble-seeds/tasks

Docs

In your tasks folder create your file with

const Task = require('@marble-seeds/tasks')

const task = new Task(async function (argv) {
  console.log(argv)

  return { foo: true }
})

if (require.main === module) {
  task.setCliHandlers()
  task.run()
} else {
  module.exports = task
}

The last part will allow you to call it as a CLI or be loaded on your app and run as part of you app

Task philosophy

Task are small units of logic that should be repetable and composable.

Task to be able have repetable tasks, we need to care about 2 concepts:

• Input/Output: To handle the inputs and outputs of a task in a easy way, task are build to be black boxes.
• Boundaries of the box

By carring about this elements logs test of task can be created by recording the 3 elements and then replay them.

boundary

To be able to treat task as black boxes, all the interactions to fetch data, save elements need to be moved to boundaries.

const task = new Task(async function (argv, { getData }) {
  const data = async getData()
  console.log(argv, data)

  return { ...data, ...argv }
}, {
  boundaries : {
    getData: async () => {
      // someting
      return data
    }
  }
})

By defining bounderies in this form, we can record the interactions from the task with other elements allowing to track them and mock them.

Boundary have 4 modes:

• Proxy: execute the function and records it
• Proxy-pass: review if the input exist, it it exist returns the previous value and if not execute the functions
• Proxy-catch: executes the function and if it throws and error, it tries to use a previews output if it exists for the input.
• Replay: review if the input exist and if it doesnt throws and error.

With this modes bounderies can be used as cache or to generate test by passing the data to a RecordTape to re-run the calls.

Task API

constructor

Takes a task action(function) and a timeout as params.

run

Runs the task action asynchronously. Takes the function arguments and a config object with a timeout option.

setCliHandlers

Lets the taks that it will run as a CLI program.

ToDos

• CLI run test and argv handler
• Document boundaries