Rate Limiting and Access Control Middleware for Dart Shelf Web Server

This Dart application implements middleware for the Shelf web server that enables rate limiting for all /api/ endpoints and restricts access to specific /api/v2 endpoints based on authorization tokens validated through the Unkey API. The solution is designed to enhance API security and manage user access while providing seamless integration for developers.

Features & Benefits

• Rate Limiting
  Limits requests to /api/ endpoints to prevent abuse.
• IP-Based Rate Limiting
  Uses the x-forwarded-for header for accurate user identification.
• Authorization for Premium Features
  Restricts /api/v2 access to users with valid Unkey API keys.
• Public API Access
  Allows unrestricted use of /api/v1 and root / endpoints.

Use Cases

• API Management
  Controls access and prevents abuse of API endpoints.
• Feature Flagging
  Enables features for testers without public exposure.
• Dynamic User Access Control
  Simplifies permission management across API versions.

Route Overview

Method	Endpoint	Required Headers	Description
GET	/	None	Returns the welcome message
GET	/api/v1/echo/<message>	x-forwarded-for: <ip>	Returns the echoed message
GET	/api/v1/users	x-forwarded-for: <ip>	Retrieves a list of users
GET	/api/v1/users/<id>	x-forwarded-for: <ip>	Retrieves a user by ID
POST	/api/v2/users	x-forwarded-for: <ip>, Authorization: Bearer <token>	Adds a new user
PUT	/api/v2/users/<id>	x-forwarded-for: <ip>, Authorization: Bearer <token>	Updates an existing user
DELETE	/api/v2/users/<id>	x-forwarded-for: <ip>, Authorization: Bearer <token>	Deletes a user by ID

Quickstart Guide

Create a Unkey Root Key

1. Navigate to Unkey Root Keys and click "Create New Root Key".
2. Name your root key.
3. Select the following workspace permissions:
   • create_key
   • read_key
   • encrypt_key
   • decrypt_key
4. Click "Create" and save your root key securely.

Create a Unkey API

1. Go to Unkey APIs and click "Create New API".
2. Enter a name for the API.
3. Click "Create".

Create a Unkey ratelimit namespace

1. Go to Unkey Ratelimits and click "Create New Namespace".
2. Enter a name for the namespace.
3. Click "Create".

Generate Your First Unkey API Key

1. From the Unkey APIs page, select your newly created API.
2. Click "Create Key" in the top right corner.
3. Fill out the form with the following suggested values:
   • Prefix: dart.rest.api
   • Owner: superuser
   • Bytes: 30
4. Click "Create" and copy the generated key. You'll use it instead of <token> in /api/v2 routes.

Running the sample

1. Clone the repository to your local machine:

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   1git clone git@github.com:unrenamed/unkey-dart
   2cd unkey-dart

2. Create a .env file in the root directory and populate it with the following environment variables:

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   1UNKEY_ROOT_KEY=your-unkey-root-key
   2UNKEY_API_ID=your-unkey-api-id
   3UNKEY_NAMESPACE=your-unkey-namespace

   Ensure you replace your-unkey-* with your actual Unkey credentials.

3. Start the server:

   You can run the example with the Dart SDK like this:

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   1$ dart run bin/server.dart
   2Server listening on port 8080

   If you have Docker Desktop installed, you can build and run with the docker command:

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   1$ docker build . -t myserver
   2$ docker run -it -p 8080:8080 myserver
   3Server listening on port 8080