chore: add readme

Author: albertilagan

.github/component_owners.yml

@@ -30,6 +30,8 @@ components:
     - markphelps
   libs/providers/flipt-web:
     - markphelps
+  libs/providers/unleash:
+    - albertilagan
   libs/providers/unleash-web:
     - jarebudev
 

libs/providers/unleash/README.md

@@ -1,15 +1,81 @@
 # unleash Provider
 
+## About this provider
+
+This provider is a community-developed implementation for Unleash which uses the official [Node Server-side SDK](https://docs.getunleash.io/reference/sdks/node).
+
+### Concepts
+
+- Boolean evaluation gets feature enabled status.
+- String, Number, and Object evaluation gets feature variant value.
+- Object evaluation should be used for JSON/CSV payloads in variants.
+
 ## Installation
 
+```shell
+$ npm install @openfeature/unleash-provider @openfeature/server-sdk
 ```
-$ npm install @openfeature/unleash-provider
+
+## Usage
+
+To initialize the OpenFeature client with Unleash, you can use the following code snippets:
+
+### Initialization
+
+```ts
+import { UnleashProvider } from '@openfeature/unleash-provider';
+
+const provider = new UnleashProvider({
+  url: 'https://YOUR-API-URL',
+  appName: 'your app',
+  customHeaders: { Authorization: 'your api key' },
+});
+
+await OpenFeature.setProviderAndWait(provider);
 ```
 
-## Building
+### Available Constructor Configuration Options
+
+Unleash has a variety of configuration options that can be provided to the `UnleashProvider` constructor.
+
+Please refer to the options described in the official [Node Server-side SDK](https://docs.getunleash.io/reference/sdks/node).
+
+### After initialization
+
+After the provider gets initialized, you can start evaluations of feature flags like so:
+
+```ts
+// Get the client
+const client = await OpenFeature.getClient();
+
+// You can now use the client to evaluate your flags
+const details = client.getBooleanValue('my-feature', false);
+```
+
+The static evaluation context can be changed if needed
+
+```ts
+const evaluationCtx: EvaluationContext = {
+  usedId: 'theuser',
+  currentTime: 'time',
+  sessionId: 'theSessionId',
+  remoteAddress: 'theRemoteAddress',
+  environment: 'theEnvironment',
+  appName: 'theAppName',
+  aCustomProperty: 'itsValue',
+  anotherCustomProperty: 'somethingForIt',
+};
+
+// changes the static evaluation context for OpenFeature
+await OpenFeature.setContext(evaluationCtx);
+```
+
+## Contribute
+
+### Building
 
 Run `nx package providers-unleash` to build the library.
 
-## Running unit tests
+### Running unit tests
 
 Run `nx test providers-unleash` to execute the unit tests via [Jest](https://jestjs.io).