scuttle-playbook

ALICE: Knock knock.

BOB: Who's there?

ALICE: Scuttlebutt.

BOB: Scuttlewhat??

Playbooks help you write tests for complex Secure Scuttlebutt apps. If you have app that builds up a complex state (such as a flumeview) from a series of messages that have been published by a number of parties, Playbooks can help with that.

A Playbook is a light structure that lets you define a "script" with one or more "actors" (users with their own key). Each line of the script specifies either a message to publish, or a test to run. The playbook ensures that each step only runs after the last has completed. It also handles creating and tearing down temporary scuttlebot servers as well as allocating feeds for the actors.

Message steps

A message step looks like step.message(actor, data) or step.message(actor, label, data)

// no label
step.message(actor, {
  type: 'test',
  moreStuff: 'whatever you want!'
})

// with label
step.message(actor, 'label' {
  type: 'test',
  moreStuff: 'whatever you want!'
})

Test steps

A test step is just a function. To handle asynchronous tests, your function can accept done, which you can call when the test is over, like this:

step.test(done => {
  sbot.whoami((err, me) => {
    t.ok(me)
    done()
  })
})

If your test is purely synchronous, you can omit the done parameter and the playbook will continue after your function completes:

step.test(() => {
  t.equal(1 + 1, 2)
  t.equal(e**(i * pi) + 1, 0)
})

Let's see how you can compose these steps together to create a playbook script.

Usage

Here's a simple example for how you might test the recognition of friendship based on mutual following. It has two actors, alice and bob, and the script has six steps:

1. publish message: alice follows bob
2. test: that bob shows up in alice's follow graph
3. publish message: bob follows alice
4. test: that alice shows up in bob's follow graph and that they are friends
5. publish message: alice unfollows bob
6. test: that they are no longer friends

Skipping over the details of doing the actual testing, it might look something like this:

const Playbook = require('scuttle-playbook')
                 .use(whatever)
                 .use(you)
                 .use(want)

// define the script
const script = sbot => (alice, bob) => [
  step.message(alice, {
    type: 'contact',
    contact: bob.id,
    following: true
  }),
  step.test(done => {
    sbot.testThatAliceFollowsBob((err, data) => done())
  }),
  step.message(bob, {
    type: 'contact',
    contact: alice.id,
    following: true
  }),
  step.test(done => {
    sbot.testThatBobAndAliceAreNowFriends((err, data) => done())
  }),
  step.message(alice, {
    type: 'contact',
    contact: bob.id,
    following: false
  }),
  step.test(done => {
    sbot.testThatAliceAndBobAreNoLongerFriends((err, data) => done())
  }),
]

const finale = () => console.log('all done')

// run it
Playbook(script, finale)

A little explanation

Note that the script takes a function with a signature like

(sbot) => (actors) => [script]

The Playbook creates an sbot instance for you and passes it in. After that, it will create actors for you based on how many parameters you specify in the second set of parameters. For instance, if your function looks like this:

sbot => (alvin, simon, theodore, larry, curly, moe) => [...]

then you will have six actors available in your script.

Examples using actual testing frameworks

See examples/ for examples of real tests using the tape test harness. Note that scuttle-playbook is designed to let you use whatever test runner you want.

Under the hood

Each time you run a script with Playbook(), a scuttlebot instance is created and destroyed. The instance is created with the {temp: true} option, which means your data will not be affected, and test data won't linger after a test is run.

Anything you pass to Playbook.use() is passed directly on to scuttlebot, so the instance that gets created will contain whatever plugins you used.

TODO

• Document refs
• Demonstrate script composition

Install

With npm installed, run

$ npm install scuttle-playbook