Refit vs RestSharp: What are the differences?

Introduction

This article will discuss the key differences between Refit and RestSharp, two popular libraries used for consuming APIs in .NET.

1. Request Creation and Configuration: Refit: Refit simplifies the request creation process by utilizing interfaces and attributes. Developers can define a Refit interface with method signatures representing the desired API endpoints, along with additional attributes to configure the endpoint's HTTP verb, route, headers, and more. RestSharp: RestSharp follows a more traditional approach, where developers manually create and configure Request objects using its API. This involves setting properties like the request method, resource URL, parameters, headers, and more.

2. API Call Execution: Refit: Refit generates an implementation for the defined interfaces at runtime, leveraging a library called DynamicProxy. This allows developers to directly call the interface methods, simplifying the API call execution process. RestSharp: RestSharp requires developers to explicitly create a RestClient instance and configure it with the desired base URL, authentication, and other settings. Developers then call the Execute() method on a RestRequest object to actually make the API call.

3. Serialization and Deserialization: Refit: Refit employs Newtonsoft.Json (JSON.NET) as its default serializer and deserializer, offering flexible customization options through attributes and settings. Developers can annotate method parameters, properties, or the entire interface with attributes to control how objects are serialized and deserialized. RestSharp: RestSharp has its own built-in serialization and deserialization mechanism. It supports XML and JSON serialization out of the box but may require additional settings for customization.

4. Async/Await Support: Refit: Refit natively supports asynchronous operations by generating methods that return Task objects. This allows developers to utilize C#'s async/await pattern, simplifying asynchronous programming when consuming APIs. RestSharp: RestSharp also provides support for asynchronous operations through the ExecuteTaskAsync() method and associated callback approach. However, it may require additional coding and may not be as intuitive as Refit's native async/await support.

5. Error Handling: Refit: Refit provides easier error handling through its built-in exception handling mechanism. By default, it throws ApiException instances for non-successful HTTP responses, which can be caught and handled in a standardized manner. RestSharp: RestSharp returns IRestResponse objects encapsulating the API response, which developers need to manually check for errors and status codes. This requires additional coding and error handling logic to handle different scenarios.

6. API Documentation Generation: Refit: Refit offers the ability to generate API documentation based on the defined interfaces and attributes. This makes it easier for developers to document and maintain the API contract in a single place. RestSharp: RestSharp does not provide native support for API documentation generation, requiring developers to rely on other tools or methods for documentation.

In summary, Refit simplifies the API consumption process by generating implementation code at runtime based on defined interfaces, providing native support for async/await, built-in error handling, and API documentation generation. RestSharp, on the other hand, follows a more traditional manual approach for request creation and configuration, requires explicit execution, allows customization of serialization, and returns IRestResponse objects for error handling.