# tas-client

## Purpose

This package is intended to be used as an endpoint client to query, refetch, and cache data from the Experimentation service (or any given endpoint). The endpoint result must follow the required structure for experimentation data.

## Development

### Building

- `npm run compile` - Compile TypeScript to JavaScript
- `npm run bundle` - Bundle the package into a single file (output: `out/bundle/tas-client.js`)
- `npm run watch` - Watch mode for TypeScript compilation
- `npm test` - Run tests

## Usage

First, your client should implement an `IExperimentationFilterProvider`, `IExperimentationTelemetry`, and `IKeyValueStorage`.


Next, they can be used in the `TASClient` constructor:

```javascript
const tasClient = new TASClient({
			filterProviders: [filterProvider],
			telemetry: telemetry,
			storageKey: storageKey,
			keyValueStorage: keyValueStorage,
			assignmentContextTelemetryPropertyName: '<assignmentContextTelemetryPropertyName>',
			telemetryEventName: '<telemetryEventName>',
			endpoint: '<tas-endpoint>',
			refetchInterval: refetchInterval,
		});
```

The client provides a variety of functions, but the most basic is `getTreatmentVariable(configId: string, name: string)`.
Once you have an instance of `IExperimentationService` you can call `getTreatmentVariable` to get the value of a treatment variable.

> NOTE: If you haven't awaited the `IExperimentationService`'s `initializePromise`, you need to use `getTreatmentVariableAsync`.