PHP Ruby Shell
Latest commit 241bca5 Feb 16, 2017 @drichelson drichelson committed on GitHub Merge pull request #62 from abacaphiliac/drop-php54
drop php54 from the integration-test VM

LaunchDarkly SDK for PHP

Code Climate

Circle CI


  1. PHP 5.5 or higher.

Quick setup

  1. Install the PHP SDK and monolog for logging with Composer

    php composer.phar require launchdarkly/launchdarkly-php
  2. After installing, require Composer's autoloader:

    require 'vendor/autoload.php';
  3. Create a new LDClient with your SDK key:

    $client = new LaunchDarkly\LDClient("your_sdk_key");

Your first feature flag

  1. Create a new feature flag on your dashboard

  2. In your application code, use the feature's key to check whether the flag is on for each user:

    $user = new LaunchDarkly\LDUser("");
    if ($client->variation("your.flag.key", $user)) {
        # application code to show the feature
    } else {
        # the code to run if the feature is off

Fetching flags

There are two approaches to fetching the flag rules from LaunchDarkly:

  • Making HTTP requests (using Guzzle)
  • Setting up the ld-daemon to store the flags in Redis

Using Guzzle

To use Guzzle it must be required as a dependency:

php composer.phar require "guzzlehttp/guzzle:6.2.1"
php composer.phar require "kevinrob/guzzle-cache-middleware:1.4.1"

It will then be used as the default way of fetching flags.

Using Redis

  1. Require Predis as a dependency:

    php composer.phar require "predis/predis:1.0.*"

  2. Create the LDClient with the Redis feature requester as an option:

    $client = new LaunchDarkly\LDClient("your_sdk_key", ['feature_requester_class' => 'LaunchDarkly\LDDFeatureRequester']);


We run integration tests for all our SDKs using a centralized test harness. This approach gives us the ability to test for consistency across SDKs, as well as test networking behavior in a long-running application. These tests cover each method in the SDK, and verify that event sending, flag evaluation, stream reconnection, and other aspects of the SDK all behave correctly.

Learn more

Check out our documentation for in-depth instructions on configuring and using LaunchDarkly. You can also head straight to the complete reference guide for this SDK.


We encourage pull-requests and other contributions from the community. We've also published an SDK contributor's guide that provides a detailed explanation of how our SDKs work.

About LaunchDarkly

  • LaunchDarkly is a continuous delivery platform that provides feature flags as a service and allows developers to iterate quickly and safely. We allow you to easily flag your features and manage them from the LaunchDarkly dashboard. With LaunchDarkly, you can:
    • Roll out a new feature to a subset of your users (like a group of users who opt-in to a beta tester group), gathering feedback and bug reports from real-world use cases.
    • Gradually roll out a feature to an increasing percentage of users, and track the effect that the feature has on key metrics (for instance, how likely is a user to complete a purchase if they have feature A versus feature B?).
    • Turn off a feature that you realize is causing performance problems in production, without needing to re-deploy, or even restart the application with a changed configuration file.
    • Grant access to certain features based on user attributes, like payment plan (eg: users on the ‘gold’ plan get access to more features than users in the ‘silver’ plan). Disable parts of your application to facilitate maintenance, without taking everything offline.
  • LaunchDarkly provides feature flag SDKs for
  • Explore LaunchDarkly