HackerAPI

HackerAPI is a .NET 8 web API that provides access to top stories from a hacker news-like service. The API uses caching to improve performance and reduce the number of requests to the external service.

Features

• Fetch top stories
• Fetch story details by ID
• Caching to improve performance
• Unit tests with NUnit and Moq

Installation

1. Clone the repository:

git clone https://github.com/yourusername/HackerAPI.git
cd HackerAPI

2. Restore the NuGet packages:

dotnet restore

3. Build the solution:

dotnet build

Usage

1. Run the application:

dotnet run --project HackerAPI

2. The API will be available at https://localhost:5001.

Endpoints

• GET /HackerAPI?count={count}: Fetch the top {count} stories.

Configuration

The API base URI and endpoints are configured in the ApiUris class located in the SantanderTest.HackerAPI.Services.Constants namespace.

Testing

The project includes unit tests using NUnit and Moq. To run the tests, use the following command:

dotnet test

Test Data

Test data is provided by the TestDataProvider class located in the HackerAPI.Tests namespace.

Project Structure

• HackerAPI: Main project containing the API implementation.
• HackerAPI.Model: Contains the data models.
• HackerAPI.Services: Contains the service classes and constants.
• HackerAPI.Tests: Contains the unit tests.

Dependencies

• .NET 8
• Microsoft.Extensions.Caching.Memory
• Microsoft.Extensions.Logging
• Moq
• NUnit
• FluentAssertions

Resiliency Features

Retry Policy

The retry policy is implemented using Polly to handle transient errors. It retries the request up to 3 times with an exponential backoff strategy.

Rate Limiting

The rate limit policy is implemented using Polly to prevent API overload. It limits the requests to 250 requests per 3 seconds with a maximum burst of 200 requests at once.

Exception Handling

The HackerController includes detailed exception handling to provide meaningful error messages and appropriate HTTP status codes.

Exception Types

• RateLimitRejectedException: Thrown when the rate limit is exceeded. Returns a 429 Too Many Requests status code.
• HttpRequestException: Thrown for HTTP request errors. Returns a 503 Service Unavailable status code.
• Exception: Catches any other unexpected exceptions. Returns a 500 Internal Server Error status code.

Logging

The service logs important information such as the number of requests made, cache hits, and errors encountered. This helps in monitoring the rate limit usage and debugging issues.

Contributing

Contributions are welcome! Please open an issue or submit a pull request.

License

This project is licensed under the MIT License.