What is the wrapper in the Asp.net Core web API?
Tags: webdev, programming, opensource, aspdotnet
Published: 2023-05-23 17:21:46

A class or component that contains the logic for performing operations or functionality is referred to as a wrapper in the context of the ASP.NET Core Web API. It serves as a bridge between the controller and the implementation in the core, adding another level of abstraction and frequently new features or behaviors.
When connecting with outside services or libraries, an ASP.NET Core Web API wrapper is frequently used. The wrapper class can handle duties like authentication, error handling, logging, and transferring the replies from the external service to a format appropriate for the API while also offering a streamlined user experience.
Here is an illustration of the idea of a wrapper in the ASP.NET Core Web API. Consider the case when an API needs to fetch.

```csharp
public interface IWeatherServiceWrapper
{
    Task<WeatherData> GetWeatherData(string location);
}

public class WeatherServiceWrapper : IWeatherServiceWrapper
{
    private readonly IWeatherService _weatherService;

    public WeatherServiceWrapper(IWeatherService weatherService)
    {
        _weatherService = weatherService;
    }

    public async Task<WeatherData> GetWeatherData(string location)
    {
        try
        {
            // Perform any necessary preprocessing or validation
            // before calling the actual weather service
          
            // Call the weather service and get the response
            var response = await _weatherService.GetWeatherAsync(location);
            
            // Perform any additional processing or mapping of the response
            
            // Return the mapped response
            return MapToWeatherData(response);
        }
        catch (Exception ex)
        {
            // Handle any errors or exceptions
            
            // Log the error
            
            // Rethrow or return an appropriate response
            throw;
        }
    }

    private WeatherData MapToWeatherData(WeatherServiceResponse response)
    {
        // Map the response from the weather service
        // to your API's WeatherData model or DTO
        // Perform any necessary transformations or mappings
        
        // Return the mapped WeatherData object
        return new WeatherData
        {
            // Populate the properties based on the response
            Temperature = response.Temperature,
            Humidity = response.Humidity,
            // ...
        };
    }
}
```

The `IWeatherService` class, which represents the actual weather service implementation in the aforementioned example, is wrapped by the `WeatherServiceWrapper` class. The weather service interaction logic is contained in the wrapper, which also handles any preparation, error handling, and the mapping of the result to the data model of the API.

By employing a wrapper, you may separate the weather service's API controller from its precise implementation details, making it simpler to maintain and switch between different service implementations as necessary. The wrapper removes the intricacies of the underlying service and offers a higher-level interface that is tailored to the requirements of the API.