This is a simple microservice that provides exchange rates for various currencies against USD.

• Bun runtime
• Hono
• An API key from Open Exchange Rates

1. Clone this repository
2. Run bun install to install dependencies
3. Copy .env.example to .env and add your Open Exchange Rates API key

Run the service with:

bun run dev

The service will be available at http://localhost:6565.

• GET /rates: Returns exchange rates for all available currencies
• GET /rates?currency=XXX: Returns the exchange rate for a specific currency (e.g., XXX)

Run the tests with:

bun test

• Using a backend framework/language of your choice, create a simple microservice that exposes a single GET endpoint /rates which returns a response for the exchange rate of 1 USD to a list of all available currencies:

{
    "rates": [
        {
            "symbol": "AED",
            "name": "United Arab Emirates Dirham",
            "rate":  3.672538
        },
        {
            "symbol": "AFN",
            "name": "Afghan Afghani",
            "rate": 66.809999
        },
        {
            "symbol": "ALL",
            "name": "Albanian Lek",
            "rate": 125.716501
        }
        ...
    ]
}

• Query all supported currency names and symbols using the appropriate endpoint.
• Query the latest exchange rates for all supported currencies using the relevant endpoint.
• Generate a combined response that includes both currency names, symbols, and their corresponding latest exchange rates.
• Ensure that if a supported currency does not have a latest rate, it returns a null value for the rate.
• Handle API errors by returning a 503 Service Unavailable response if the Open Exchange Rates API is unavailable or experiences an error.
• Introduce a GET parameter to this GET endpoint (eg: /rates?currency=AED) to filter just the queried currency in the response. If the queried currency is not supported, your endpoint should return a 404 Not Found response.

{
  "rates": [
    {
      "symbol": "AED",
      "name": "United Arab Emirates Dirham",
      "rate": 3.672538
    }
  ]
}