@openfeature/config-cat-provider

ConfigCat Provider

This provider is an implementation for ConfigCat a managed feature flag service.

Installation

$ npm install @openfeature/config-cat-provider

Required peer dependencies

The OpenFeature SDK is required as peer dependency.

The minimum required version of @openfeature/server-sdk currently is 1.13.5.

The minimum required version of configcat-node currently is 11.0.0.

$ npm install @openfeature/server-sdk configcat-node

Usage

The ConfigCat provider uses the ConfigCat Node.js SDK.

It can be created by passing the ConfigCat SDK options to ConfigCatProvider.create.

The available options can be found in the ConfigCat Node.js SDK.

Example using the default configuration

import { ConfigCatProvider } from '@openfeature/config-cat-provider';

const provider = ConfigCatProvider.create('<sdk_key>');
OpenFeature.setProvider(provider);

Example using different polling options and a setupHook

import { ConfigCatProvider } from '@openfeature/config-cat-provider';

const provider = ConfigCatProvider.create('<sdk_key>', PollingMode.LazyLoad, {
  setupHooks: (hooks) => hooks.on('clientReady', () => console.log('Client is ready!')),
});

OpenFeature.setProvider(provider);

Evaluation Context

The OpenFeature Evaluation Context is mapped to the ConfigCat user object.

The ConfigCat user object has three known attributes, and allows for additional attributes. The following shows how the attributes are mapped:

OpenFeature EvaluationContext Field	ConfigCat User Field	Required
targetingKey	identifier	yes
email	email	no
country	country	no
Any Other	custom	no

The custom types are mapped the following way:

OpenFeature EvaluationContext Field Type	ConfigCat User Field Type
string	string
number	number
boolean	string
Array	Array
Array	Array
object	string

The following example shows the conversion between an OpenFeature Evaluation Context and the corresponding ConfigCat User:

OpenFeature

{
  "targetingKey": "test",
  "email": "email",
  "country": "country",
  "customString": "customString",
  "customNumber": 1,
  "customBoolean": true,
  "customObject": {
    "prop1": "1",
    "prop2": 2
  },
  "customStringArray": ["one", "two"],
  "customArray": [
    1,
    "2",
    false
  ]
}

ConfigCat

{
  "identifier": "test",
  "email": "email",
  "country": "country",
  "custom": {
    "customString": "customString",
    "customBoolean": "true",
    "customNumber": 1,
    "customObject": "{\"prop1\":\"1\",\"prop2\":2}",
    "customStringArray": ["one", "two"],
    "customArray": "[1,\"2\",false]"
  }
}

Events

The ConfigCat provider emits the following OpenFeature events:

• PROVIDER_READY
• PROVIDER_ERROR
• PROVIDER_CONFIGURATION_CHANGED

Building

Run nx package providers-config-cat to build the library.

Running unit tests

Run nx test providers-config-cat to execute the unit tests via Jest.