A/B Testing React Components


Wrap components in and nest in . A variant is chosen randomly and saved to local storage.

``js




Report to your analytics provider using the emitter. Helpers are available for Mixpanel and Segment.com.

`js
emitter.addPlayListener(function(experimentName, variantName){
mixpanel.track("Start Experiment", {name: experimentName, variant: variantName});
});
`

Please ★ on GitHub!

Table of Contents

- Installation
- Usage
- Standalone Component
- Coordinate Multiple Components
- Weighting Variants
- Debugging
- Server Rendering
- Example
- With Babel
- Alternative Libraries
- Resources for A/B Testing with React
- API Reference
-
-
- emitter
- emitter.emitWin(experimentName)
- [emitter.addActiveVariantListener([experimentName, ] callback)](#emitteraddactivevariantlistenerexperimentname--callback)
- [emitter.addPlayListener([experimentName, ] callback)](#emitteraddplaylistenerexperimentname--callback)
- [emitter.addWinListener([experimentName, ] callback)](#emitteraddwinlistenerexperimentname--callback)
- [emitter.defineVariants(experimentName, variantNames [, variantWeights])](#emitterdefinevariantsexperimentname-variantnames--variantweights)
- emitter.setActiveVariant(experimentName, variantName)
- emitter.getActiveVariant(experimentName)
- emitter.getSortedVariants(experimentName)
- Subscription
- subscription.remove()
- experimentDebugger
- experimentDebugger.enable()
- experimentDebugger.disable()
- mixpanelHelper
- Usage
- mixpanelHelper.enable()
- mixpanelHelper.disable()
- segmentHelper
- Usage
- segmentHelper.enable()
- segmentHelper.disable()
- How to contribute
- Requisites
- Browser Coverage
- Running Tests

Installation

react-ab-test is compatible with React 0.14.x and 0.15.x.

`bash
npm install react-ab-test
`

Usage

$3

Try it on JSFiddle

`js

var Experiment = require("react-ab-test/lib/Experiment");
var Variant = require("react-ab-test/lib/Variant");
var emitter = require("react-ab-test/lib/emitter");

var App = React.createClass({
onButtonClick: function(e){
this.refs.experiment.win();
},
render: function(){
return

`

$3

Try it on JSFiddle

`js

var Experiment = require("react-ab-test/lib/Experiment");
var Variant = require("react-ab-test/lib/Variant");
var emitter = require("react-ab-test/lib/emitter");

// Define variants in advance.
emitter.defineVariants("My Example", ["A", "B", "C"]);

var Component1 = React.createClass({
render: function(){
return



`

$3

Try it on JSFiddle

Use emitter.defineVariants() to optionally define the ratios by which variants are chosen.

`js

var Experiment = require("react-ab-test/lib/Experiment");
var Variant = require("react-ab-test/lib/Variant");
var emitter = require("react-ab-test/lib/emitter");

// Define variants and weights in advance.
emitter.defineVariants("My Example", ["A", "B", "C"], [10, 40, 40]);

var App = React.createClass({
render: function(){
return

`

$3

The debugger attaches a fixed-position panel to the bottom of the element that displays mounted experiments and enables the user to change active variants in real-time.

The debugger is wrapped in a conditional if(process.env.NODE_ENV === "production") {...} and will not display on production builds using envify.

Try it on JSFiddle

`js

var Experiment = require("react-ab-test/lib/Experiment");
var Variant = require("react-ab-test/lib/Variant");
var experimentDebugger = require("react-ab-test/lib/debugger");

experimentDebugger.enable();

var App = React.createClass({
render: function(){
return

`


$3

A with a userIdentifier property will choose a consistent suitable for server side rendering.

See ./examples/isomorphic for a working example.

#### Example

The component in Component.jsx:

`js

var React = require("react");
var Experiment = require("react-ab-test/lib/Experiment");
var Variant = require("react-ab-test/lib/Variant");

module.exports = React.createClass({
propTypes: {
userIdentifier: React.PropTypes.string.isRequired
},
render: function(){
return

`

We use a session ID for the userIdentifier property in this example, although a long-lived user ID would be preferable. See server.js:

`js
require("babel/register")({only: /jsx/});

var express = require('express');
var session = require('express-session');
var React = require("react");
var ReactDOMServer = require("react-dom/server");
var Component = require("./Component.jsx");
var abEmitter = require("react-ab-test/lib/emitter")

var app = express();

app.set('view engine', 'ejs');

app.use(session({
secret: 'keyboard cat',
resave: false,
saveUninitialized: true
}));

app.get('/', function (req, res) {
var reactElement = React.createElement(Component, {userIdentifier: req.sessionID});
var reactString = ReactDOMServer.renderToString(reactElement);
abEmitter.rewind();
res.render('template', {
sessionID: req.sessionID,
reactOutput: reactString
});
});

app.use(express.static('www'));

app.listen(8080);
`

Remember to call abEmitter.rewind() to prevent memory leaks.

An EJS template in template.ejs:

`html









On the client in app.jsx:

`js
var React = require('react');
var ReactDOM = require('react-dom');
var Component = require("../Component.jsx");

var container = document.getElementById("react-mount");

ReactDOM.render(, container);
`

$3

Code from ./src is written in JSX and transpiled into ./lib using Babel. If your project uses Babel you may want to include files from ./src directly.

Alternative Libraries

Experiment container component. Children must be of type Variant.

* Properties:
* name - Name of the experiment.
* Required
* Type: string
* Example: "My Example"
* userIdentifier - Distinct user identifier. When defined, this value is hashed to choose a variant if defaultVariantName or a stored value is not present. Useful for server side rendering.
* Optional
* Type: string
* Example: "7cf61a4521f24507936a8977e1eee2d4"
* defaultVariantName - Name of the default variant. When defined, this value is used to choose a variant if a stored value is not present. This property may be useful for server side rendering but is otherwise not recommended.
* Optional
* Type: string
* Example: "A"

$3

Variant container component.

* Properties:
* name - Name of the variant.
* Required
* Type: string
* Example: "A"

$3

Event emitter responsible for coordinating and reporting usage. Extended from facebook/emitter.

#### emitter.emitWin(experimentName)

Emit a win event.

* Return Type: No return value
* Parameters:
* experimentName - Name of an experiment.
* Required
* Type: string
* Example: "My Example"

#### emitter.addActiveVariantListener([experimentName, ] callback)

Listen for the active variant specified by an experiment.

* Return Type: Subscription
* Parameters:
* experimentName - Name of an experiment. If provided, the callback will only be called for the specified experiment.
* Optional
* Type: string
* Example: "My Example"
* callback - Function to be called when a variant is chosen.
* Required
* Type: function
* Callback Arguments:
* experimentName - Name of the experiment.
* Type: string
* variantName - Name of the variant.
* Type: string

#### emitter.addPlayListener([experimentName, ] callback)

Listen for an experiment being displayed to the user. Trigged by the React componentWillMount lifecycle method.

* Return Type: Subscription
* Parameters:
* experimentName - Name of an experiment. If provided, the callback will only be called for the specified experiment.
* Optional
* Type: string
* Example: "My Example"
* callback - Function to be called when an experiment is displayed to the user.
* Required
* Type: function
* Callback Arguments:
* experimentName - Name of the experiment.
* Type: string
* variantName - Name of the variant.
* Type: string

#### emitter.addWinListener([experimentName, ] callback)

Listen for a successful outcome from the experiment. Trigged by the emitter.emitWin(experimentName) method.

* Return Type: Subscription
* Parameters:
* experimentName - Name of an experiment. If provided, the callback will only be called for the specified experiment.
* Optional
* Type: string
* Example: "My Example"
* callback - Function to be called when a win is emitted.
* Required
* Type: function
* Callback Arguments:
* experimentName - Name of the experiment.
* Type: string
* variantName - Name of the variant.
* Type: string

#### emitter.defineVariants(experimentName, variantNames [, variantWeights])

Define experiment variant names and weighting. Required when an experiment spans multiple components containing different sets of variants.

If variantWeights are not specified variants will be chosen at equal rates.

The variants will be chosen according to the ratio of the numbers, for example variants ["A", "B", "C"] with weights [20, 40, 40] will be chosen 20%, 40%, and 40% of the time, respectively.

* Return Type: No return value
* Parameters:
* experimentName - Name of the experiment.
* Required
* Type: string
* Example: "My Example"
* variantNames - Array of variant names.
* Required
* Type: Array.
* Example: ["A", "B", "C"]
* variantWeights - Array of variant weights.
* Optional
* Type: Array.
* Example: [20, 40, 40]

#### emitter.setActiveVariant(experimentName, variantName)

Set the active variant of an experiment.

* Return Type: No return value
* Parameters:
* experimentName - Name of the experiment.
* Required
* Type: string
* Example: "My Example"
* variantName - Name of the variant.
* Required
* Type: string
* Example: "A"

#### emitter.getActiveVariant(experimentName)

Returns the variant name currently displayed by the experiment.

* Return Type: string
* Parameters:
* experimentName - Name of the experiment.
* Required
* Type: string
* Example: "My Example"

#### emitter.getSortedVariants(experimentName)

Returns a sorted array of variant names associated with the experiment.

* Return Type: Array.
* Parameters:
* experimentName - Name of the experiment.
* Required
* Type: string
* Example: "My Example"

$3

Returned by the emitter's add listener methods. More information available in the facebook/emitter documentation.

#### subscription.remove()

Removes the listener subscription and prevents future callbacks.

* Parameters: No parameters

$3

Debugging tool. Attaches a fixed-position panel to the bottom of the element that displays mounted experiments and enables the user to change active variants in real-time.

The debugger is wrapped in a conditional if(process.env.NODE_ENV === "production") {...} and will not display on production builds using envify.

#### experimentDebugger.enable()

Attaches the debugging panel to the element.

* Return Type: No return value

#### experimentDebugger.disable()

Removes the debugging panel from the element.

* Return Type: No return value

$3

Sends events to Mixpanel. Requires window.mixpanel to be set using Mixpanel's embed snippet.

#### Usage

When the is mounted, the helper sends an Experiment Play event using mixpanel.track(...) with Experiment and Variant properties.

When a win is emitted the helper sends an Experiment Win event using mixpanel.track(...) with Experiment and Variant properties.

Try it on JSFiddle

`js

var Experiment = require("react-ab-test/lib/Experiment");
var Variant = require("react-ab-test/lib/Variant");
var mixpanelHelper = require("react-ab-test/lib/helpers/mixpanel");

// window.mixpanel has been set by Mixpanel's embed snippet.
mixpanelHelper.enable();

var App = React.createClass({
onButtonClick: function(e){
emitter.emitWin("My Example");
// mixpanelHelper sends the 'Experiment Win' event, equivalent to:
// mixpanel.track('Experiment Win', {Experiment: "My Example", Variant: "A"})
},
componentWillMount: function(){
// mixpanelHelper sends the 'Experiment Play' event, equivalent to:
// mixpanel.track('Experiment Play', {Experiment: "My Example", Variant: "A"})
},
render: function(){
return

`

#### mixpanelHelper.enable()

Add listeners to win and play events and report results to Mixpanel.

* Return Type: No return value

#### mixpanelHelper.disable()

Remove win and play listeners and stop reporting results to Mixpanel.

* Return Type: No return value

$3

Sends events to Segment. Requires window.analytics to be set using Segment's embed snippet.

#### Usage

When the is mounted, the helper sends an Experiment Viewed event using segment.track(...) with experimentName and variationName properties.

When a win is emitted the helper sends an Experiment Won event using segment.track(...) with experimentName and variationName properties.

Try it on JSFiddle

`js

var Experiment = require("react-ab-test/lib/Experiment");
var Variant = require("react-ab-test/lib/Variant");
var segmentHelper = require("react-ab-test/lib/helpers/segment");

// window.analytics has been set by Segment's embed snippet.
segmentHelper.enable();

var App = React.createClass({
onButtonClick: function(e){
emitter.emitWin("My Example");
// segmentHelper sends the 'Experiment Won' event, equivalent to:
// segment.track('Experiment Won', {experimentName: "My Example", variationName: "A"})
},
componentWillMount: function(){
// segmentHelper sends the 'Experiment Viewed' event, equivalent to:
// segment.track('Experiment Viewed, {experimentName: "My Example", variationName: "A"})
},
render: function(){
return

`

#### segmentHelper.enable()

Add listeners to win and play events and report results to Segment.

* Return Type: No return value

#### segmentHelper.disable()

Remove win and play listeners and stop reporting results to Segment.

* Return Type: No return value

How to contribute

Then you can:
- Apply your changes :sunglasses:
- Build your changes with npm run build
- Test your changes with npm test
- Lint your changes with npm run lint
- And finally open the PR! :tada:

$3

`bash

npm test

`

On Browserstack:

`bash

BROWSERSTACK_USERNAME=YOUR_USERNAME BROWSERSTACK_ACCESS_KEY=YOUR_ACCESS_KEY npm test

``