Replacing persona with stubbyid (http://toolness.github.io/stubbyid/) for testing when using Doorknob & Browserify

_persona-id_transform.js

// replace persona-id's persona.js with stubbyid.js, modified to have an `exports`
// ./_persona-id_stubbyid_js is a copy of https://github.com/toolness/stubbyid/blob/gh-pages/stubbyid.js

const through      = require('through2')
    , fs           = require('fs')
    , path         = require('path')
    , stubbyidFile = path.join(__dirname, '_persona-id_stubbyid_js')

var stubbyid

module.exports = function (file) {
  if (!stubbyid) {
    stubbyid = fs.readFileSync(stubbyidFile, 'utf8')
    stubbyid += ';module.exports = navigator.id;'
  }

  if (/\/persona\.js$/.test(file)) {
    console.log('replacing', file, 'with', stubbyidFile)
    return through(
        function (chunk, enc, callback) { callback() }
      , function (callback) { this.push(stubbyid); callback() }
    )
  }
  return through()
}

doorknob_setup.js

// wherever doorknob is set up as a filter/middleware

const Doorknob = require('doorknob')
    , audience = process.env.PERSONA_AUDIENCE || 'http://localhost:3000'
    , devMode  = process.env.PERSONA_STUB

var doorknob = Doorknob(audience)

if (devMode) {
  doorknob.persona.verify = function (assertion, cb) {
    console.log('stubbing out auth call to persona for (', assertion, ')')
    cb(null, { email: assertion })
  }
}

function filter (req, res, next) {
  doorknob(req, res, function(err, profile) {

    // whatever needs to be done for your app...

    req.profile = profile

    if (profile.loggingIn)
      return // bypass

    next()
  })
}

script.js

// route that handles /js/script.js or whatever

const path       = require('path')
    , browserify = require('browserify')

const index   = path.join(__dirname, '../../browser-lib/index.js')
    , devMode = process.env.PERSONA_STUB

// replace persona-id's persona.js with stubbyid.js
function personaStubFilter (p) {
  if (p.name == 'persona-id') {
    if (!p.browserify)
      p.browserify = {}
    ;(p.browserify.transform || (p.browserify.transform = []))
      .push(path.join(__dirname, './_persona-id_transform.js'))
  }
  return p
}

// replace with whatever your web 'framework' uses, this is a splinky handler
function handler (context, callback) {
  context.setContentType('text/javascript')
  browserify(index)
    .bundle(devMode ? { packageFilter: personaStubFilter } : {})
    .pipe(context.response)
}