A (experimental, WIP) C# source generator for generating REST clients out of OpenApi specifications. Currently, supports .NET 8 SDK. Generated code can target as low as netstandard2.0, but with additional polyfills needed.

• Add NuGet package RESTly to your project
• Add a OpenApi specification as AdditionalFiles to your project
• Add assembly attribute RestlyClient into your code with the name of the OpenApi specification file and the name of the api client to generate
• The generated API client is located in the Restly namespace

This source generator generates AOT compatible code from version 0.7 onwards. For using AOT there is the need to add a client library project additionally to the application itself. In the application project the JSON serialization context for the generated API models must be defined. The split into projects is necessary as RESTly and JSON serialization context need source generators and those can not be chained.

Building RESTly client libraries makes a new .NET SDK version necessary. Target is to support at least the latest LTS version (but no guarantee).

With RESTly it is possible to build REST clients for older .NET versions netstandard 2.0 and onwards compatible (, see https://learn.microsoft.com/en-us/dotnet/standard/net-standard). When building for older .NET versions, additional dependencies might become necessary. This can be seen in the ClientLibrary example project.

There is one possible issue with file upload. When using minimal APIs with the .WithOpenApi() extension method and call parameters of type IFormFile the generated schema contains no names for the form field names. This makes the automated generation of client code hardly possible. For using such endpoints the correct names must be given in the Name field of the body parameter.