LaunchDarkly Sample Client-Side Node.js Application

We've built a simple console application that demonstrates how LaunchDarkly's SDK works. Below, you'll find the basic build procedure, but for more comprehensive instructions, you can visit your Quickstart page.

Please note that this sample application demonstrates how to use the LaunchDarkly Client-Side SDK for Node.js which is designed primarily for use by code that is deployed to an end user, such as in a desktop application or a smart device. It follows the client-side LaunchDarkly model for single-user contexts (much like our mobile or JavaScript SDKs). It is not intended for use in multi-user systems such as web servers and applications.

For a sample application demonstrating how to use LaunchDarkly in server-side Node.js applications, refer to our Server-side Node.js SDK sample application.

Build instructions

1. Install the LaunchDarkly Client-Side Node.js SDK by running npm install

2. Edit index.js and set the value of environmentId to your LaunchDarkly client-side ID. If there is an existing boolean feature flag in your LaunchDarkly project that you want to evaluate, set featureFlagKey to the flag key.

  const environmentId = "1234567890abcdef";

  const featureFlagKey = "my-flag";

3. Run node index.js

You should see the message "Feature flag '<flag key>' is <true/false> for this user".