ember-feature-flags
An Ember CLI addon for managing feature flags in Ember.js applications.
What is ember-feature-flags?
ember-feature-flags is an Ember CLI addon that provides a service and template helpers for implementing feature flags in Ember.js applications. It allows developers to toggle features on and off at runtime without redeploying code, enabling gradual rollouts, A/B testing, and environment-specific configurations.
Ember.js developers building applications that require controlled feature releases, such as those managing gradual rollouts, A/B tests, or environment-specific feature toggles.
Developers choose this addon for its seamless integration with Ember's conventions, offering a declarative API through an injectable service and template helpers, along with built-in test support and environment configuration for maintainable feature management.
Overview
Ember CLI addon for feature flags
Use Cases
Best For
- Implementing gradual feature rollouts in Ember.js applications without redeploying code.
- Conducting A/B testing by toggling features dynamically for different user segments.
- Managing environment-specific feature configurations (e.g., enabling features in development but not in production).
- Conditionally rendering UI elements in Ember templates based on feature flag states.
- Testing feature-dependent components and acceptance tests with dedicated test helpers.
- Debugging disabled feature flags with optional logging for flag misses.
Not Ideal For
- Projects not built with Ember.js, as this addon is framework-specific and won't integrate with other JavaScript frameworks.
- Teams needing server-side feature flag evaluation for SEO or initial render optimization, since all toggling is client-side in JavaScript.
- Applications requiring integration with external feature management platforms (e.g., LaunchDarkly, Split.io) for centralized control, as this addon is a simple, in-app solution.
- Scenarios where feature flags must persist across user sessions without custom implementation, as the addon manages flags in memory with no built-in persistence.
Pros & Cons
Pros
Provides an injectable features service and template helpers that align with Ember's conventions, making it easy to adopt in existing Ember apps, as shown in the controller and template examples.
Flags can be dynamically enabled or disabled using methods like enable and disable, with bound reactivity for automatic UI updates without manual refreshes.
Allows pre-configuring flags in config/environment.js for different deployment environments, enabling easy management of features across dev, staging, and production.
Includes enableFeature and disableFeature test helpers for integration and acceptance testing, ensuring reliable testing of feature-dependent code without mocks.
Cons
Lacks server-side flag evaluation, which can be a drawback for server-rendered Ember apps or scenarios where flags need to be set before initial page load for SEO.
Flag states are managed in memory and reset on page reload; the README shows no built-in way to persist flags across sessions, requiring custom integration with backends.
The setup method resets all previously configured flags, which can be problematic if flags are set incrementally or from multiple sources, as noted in the README.
Tightly coupled with Ember versions (e.g., requires specific addon versions for older Ember releases), adding maintenance overhead and reducing flexibility for hybrid or migrating projects.
Frequently Asked Questions
Related Projects
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