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Flagsmith Ruby SDK

The SDK clients for Ruby Flagsmith allows you to manage feature flags and remote config across multiple projects, environments and organisations.

The source code for the client is available on Github.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See running in production for notes on how to deploy the project on a live system.


VIA gem:

gem install flagsmith

Basic Usage

The SDK is initialised against a single environment within a project on, for example the Development or Production environment. You can find your environment key in the Environment settings page.



Retrieving feature flags for your project

require "flagsmith"

flagsmith ="<<Your API KEY>>")

if flagsmith.get_value("font_size")
# Do something awesome with the font size

if flagsmith.feature_enabled?("does_not_exist")
#do something
#do nothing, or something else

Available Options

PropertyDescriptionRequiredDefault ValueEnvironment Key
api_keyDefines which project environment you wish to get flags for. example ACME Project - Staging.YESnullFLAGSMITH_API_KEY
urlUse this property to define where you're getting feature flags from, e.g. if you're self hosting.NO

Available Functions

initInitialize the sdk against a particular environment
feature_enabled?(key)Get the value of a particular feature e.g. flagsmith.feature_enabled?("powerUserFeature") // true
feature_enabled?(key, user_id, default = false)Get the value of a particular feature for a user e.g. flagsmith.feature_enabled?("powerUserFeature", 1234) // true
get_value(key)Get the value of a particular feature e.g. flagsmith.get_value("font_size") // 10
get_value(key, user_id, default = nil)Get the value of a particular feature for a specified user e.g. flagsmith.get_value("font_size", 1234) // 15
get_flags()Trigger a manual fetch of the environment features, if a user is identified it will fetch their features
get_flags(user_id)Trigger a manual fetch of the environment features with a given user id
set_trait(user_id, trait, value)Set the value of a trait for the given user id

Identifying Users

Identifying users allows you to target specific users from the Flagsmith dashboard. You can include an optional user identifier as part of the feature_enabled? and get_value methods to retrieve unique user flags and variables.