pivot

Simple feature, multi-variant and A/B testing

pivot

pivot is a simple feature multi-variant and A/B testing framework for node and component.

It is designed to have a pluggable backend and provide a common interface to each testing strategy.

npm install --save pivot
component install CamShaft/pivot

TODO

TODO

Start by initializing pivot

/**
 * Module dependencies
 */
var pivot = require("pivot");
 
var experiments = pivot();

You'll need to tell it about the following methods:

This method looks up the variant settings in the backend. It is called any time pivot encounters a new feature.

experiments.lookup(function(namevariantsdone){
  /**
   * We can do a few things here:
   *
   *   * Lookup our feature settings locally
   *   * If we dont have it, notify an admin control panel page
   *   * Log outdated features; either ones that should be integrated or ones that should be removed
   */
 
  var settings = []; // can come from anywhere: database, REST api, local json file, etc 
 
  done(null, settings);
});

This method takes the settings from the last call and assigns them to a user.

experiments.assign(function(namesettingsuserdone){
  /**
   * If the variant is a group, we can inspect the `user` object to check where they fall
   * If the variant is a weight, we can implement our own random assignment algorithm
   *
   * The callback expects the name of the variant chosen for the given user
   */
 
  // For this example we're just going to assign the first variant to everyone 
  done(null, settings[0]);
});

If you plan on using it paired with express/connect, you can also define the following. Otherwise, pivot will serialize/deserialize using the pivot cookie and req.user.

experiments.serialize(function(featuresreqresnext){
  // Save the features for the user 
  next();
});
experiments.deserialize(function(reqresnext){
  // Retrieve the features for the request 
  var features = {}; // can come from anywhere i.e. cookies, session, database 
  next(null, features);
});
experiments.findUser(function(reqresnext){
  // Give the user for the request to pivot 
  next(null, req.user);
});

Once you have told pivot how to do things you can start adding features into the system:

// Variants, be default, are [false, true] 
experiments.feature("my-cool-test");
 
// You can also add multi-variant 
experiments.feature("my-other-test", ["blue", "red", "green"]);

Now you can ask pivot to assign a variant to a user:

var user = {}; // pull from your user info 
 
experiments.variant("my-cool-test", user, function(errvariant){
  // do something based on the value of variant 
})

variant is either true or false depending on how we implemented the assign method.

If you are using express/connect pivot comes with some batteries included:

/**
 * Module dependencies
 */
var express = require("express")
  , pivot = require("pivot");
 
/**
 * Create our server and experiments
 */
var app = module.exports = express()
  , experiments = pivot();
 
/**
 * Add our experiment setup to express
 */
app.use(experiments);
 
/**
 * Configure pivot here with the required methods
 */
...
 
experiments.feature("landing-page", ["minimal", "fancy"]);
 
app.get("/", function(reqresnext){
  var view = res.locals.features["landing-page"]; // either "minimal" or "fancy" 
  res.render(view);
});

res.locals.features is now populated with all of the enabled features for the user.

npm install
npm test