# RFC 001: Endpoint Level Testing

## Summary

Endpoints will be tested via `undici`'s `MockAgent`, rather than using an ordered set of request/response pairs like `matrix-js-sdk`.

## Problem 
<sub>With the `matrix-js-sdk` approach</sub>

Besides being tedious and ugly, this approach is brittle as any change would easily break tests if anything route-related changed, despite no behaviour actually being involved.

Furthermore, as per [Postman API testing](https://www.postman.com/api-platform/api-testing/#contract-testing), `matrix-js-sdk` tests are even more brittle as they rely on order rather than the APIs actual contract.

## Proposal

Taking inspiration from [discord.js/rest](https://github.com/discordjs/discord.js/tree/main/packages/rest), we will use `undici`'s `MockAgent`, which will intercept the requests at the network-layer. We will also create a small hook named `TBD` that'll provide the `MockAgent` and disables network access for ease of testing.

An example could look like this:
```ts
// https://spec.matrix.org/v1.19/client-server-api/#get_matrixclientv3accountwhoami
import { useHomeserver, expect } from '@matrix-nebu/test';

const origin = "https://homeserver.test";
const homeserver = useHomeserver(origin);
const client = new Client({ baseUrl: origin, ... });


homeserver
  .intercept({
    path: "/_matrix/client/v3/account/whoami",
    method: "GET",
    headers: { authorization: "Bearer syt_drainpixie_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" },
  })
  .reply(200, { user_id: "@drainpixie:homeserver.test", device_id: "test" });
  
await expect(client.whoami()).resolves.toEqual({
  user_id: "@drainpixie:homeserver.test",
  device_id: "test",
});
```

## Future
- Automated CI checks against the Matrix OpenAPI Spec
- E2E against real homeservers