Example usage

Once you have installed the JavaScript (Node) SDK, import the Optimizely Feature Experimentation library into your code, get your project's datafile, and instantiate a client. Then, you can use the client to evaluate flag rules, including A/B tests and flag deliveries.

This example demonstrates the basic usage of each of these concepts:

1. Evaluate a flag with the key product_sort using the Decide method. As a side effect, the Decide function also sends a decision event to Optimizely Feature Experimentation to record that the current user has been exposed to the experiment.

2. Conditionally execute your feature code. You have a couple of options:

• Fetch the flag enabled state, then check a configuration variable on the flag called sort_method. The SDK evaluates your flag rules and determines what flag variation the user is in, and therefore which sort method variable they should see.
• Fetch on the flag variation, then run 'control' or 'treatment' code.

3. Use event tracking to track an event called purchased. This conversion event measures the impact of an experiment. Using the Track Event method, the purchase is automatically attributed back to the running A/B test for which we made a decision, and the SDK sends a network request to Optimizely Feature Experimentation via the customizable event dispatcher so we can count it in your Results page.

const optimizely = require("@optimizely/optimizely-sdk");

const optimizelyClient = optimizely.createInstance({
  sdkKey: "<Your_SDK_KEY>" // Provide the sdkKey of your desired environment here
});
optimizelyClient.onReady().then(() => {
  var attributes = { logged_in: true };
  var user = optimizelyClient.createUserContext('user123', attributes);

  var decision = user.decide('product_sort');
  var variationKey = decision['variationKey'];

  if (variationKey === null) {
    console.log(' decision error: ', decision['reasons']);
  }

  var enabled = decision['enabled'];

  if (enabled) {
    var sortMethod = decision.variables['sort_method'];
    // execute code for sort method value
  }

  if (variationKey === 'control') {
    // Execute code for control variation
  } else if (variationKey === 'treatment') {
    // Execute code for treatment variation
  }
   
  // Track an event
  user.trackEvent('purchased');
});