# API Mock Server (/docs/experiments/api-mock-server)



Create configurable mock API responses (path, method, status, JSON body, optional delay) stored in **Workers KV**. Any matching request to `/mock/:slug` returns the configured response.

## Features [#features]

* POST /configs - create a mock and receive a slug
* GET /configs - list all mocks
* GET /mock/:slug - serve the configured response
* DELETE /configs/:slug - remove a mock

## API Reference [#api-reference]

### POST /configs [#post-configs]

Create a mock endpoint configuration.

**`path`** `string` (required) - Mock path (must start with `/`).

**`method`** `string` (required) - HTTP method.

**`status`** `number` (required) - Response status (100–599).

**`body`** `object` (required) - JSON response body.

**`delayMs`** `number` (optional) - Artificial delay (0–30000 ms).

### GET /mock/:slug [#get-mockslug]

Serve the mock when the request method matches the stored config.

### DELETE /configs/:slug [#delete-configsslug]

Delete a mock by slug.

#### Error Codes [#error-codes]

* `400` - `INVALID_BODY`, validation errors
* `404` - `NOT_FOUND`

## Use Cases [#use-cases]

* Stub third-party APIs during frontend development
* Demo API integrations without standing up a full backend
* Test client retry and timeout behavior with configurable delays

## Limitations [#limitations]

* Requires a KV namespace binding
* No authentication on config endpoints
* Mocks are global to the namespace; not multi-tenant

## Deployment [#deployment]

<Steps>
  <Step>
    ### Click the deploy button [#click-the-deploy-button]

    [![Deploy to Cloudflare Workers](https://deploy.workers.cloudflare.com/button)](https://deploy.workers.cloudflare.com/?url=https://github.com/shrinathsnayak/cloudflare-experiments/tree/main/apps/experiments/api-mock-server)
  </Step>

  <Step>
    ### Configure bindings [#configure-bindings]

    Create a KV namespace and set its id in `wrangler.json` under `MOCKS`.
  </Step>

  <Step>
    ### Test your deployment [#test-your-deployment]

    See the experiment README for curl examples.
  </Step>
</Steps>

## Local Development [#local-development]

```bash
cd apps/experiments/api-mock-server
npm install
npm run dev
```

## Configuration [#configuration]

Create a KV namespace and set its id in `wrangler.json` under `MOCKS`.

## Cloudflare Features Used [#cloudflare-features-used]

* **[Workers](https://developers.cloudflare.com/workers/)**
* **[Workers KV](https://developers.cloudflare.com/kv/)**