Automatically generate TypeScript client code for ASP.NET Core controllers

1. Both NSwag and Swashbuckle/swagger-codegen are awesome.

   2. Typewriter is another awesome option.

   3. So, here is how I would take the decision:

      • Need to generate TypeScript Models as per the C# models, go for TypeWriter

      • Need to generate complete client side code with command line that you can add as a build or publish step go for Swagger Code Gen

      • Need to play with the generated Swagger Spec or Generated Code to add your customizations - go for NSwag

      • Need to show Client inline code snippets in Swagger UI, use SwaggerUI-snippets

You can add Swashbuckle to your ASP.NET Core webapp and then generate Swagger/OpenAPI spec.

With the Swagger/OpenAPI spec, you can then use Swagger Codegen to generate not only TypeScript API clients (Node, Angular, Angular2, Fetch), but also API clients in C#, Java, JS, Swift, etc as well as API documentation.

The easiest way to try Swagger Codegen is to use https://editor.swagger.io by importing your spec and then select the target API client/server you want to generate. (https://editor.swagger.io leverages https://generator.swagger.io to generate code and generator.swagger.io is powered by Swagger Codegen)

Swagger Codegen can also generate server stubs in C# Nancyfx or ASP.NET core so you may consider following the contract-first approach by writing the spec using https://editor.swagger.io and then generating both API clients and server stubs.

UPDATE: On May 2018, about 50 top contributors and template creators of Swagger Codegen decided to fork Swagger Codegen to maintain a community-driven version called OpenAPI Generator. Please refer to the Q&A for more information.

Another option is NSwag which can generate Swagger specs from your ASP.NET (Core) controllers and TypeScript clients from this Swagger spec (for Angular, AngularJS, Fetch, etc.). The integration is very simple and it supports many advanced features (inheritance, named enums, code extensions, etc).

http://NSwag.org

Using the NSwagStudio UI it is very simple to get started and then you can automate everything with NPM package (i.e. running the config file in the cmd line).

I'm one of the authors of the project.