speakeasy VS NSwag

I’ve built conviction that code generation only gets useful in the long term when it is entirely deterministic, or filtered through humans. Otherwise it is almost always technical debt. Hence LLM code generation products are a cool toy, but no sensible teams will use them without an amazing “Day 2” workflow.

As an example, in my day job (https://speakeasyapi.dev), we sell code generation products using the OpenAPI specification to generate downstream artefacts (language SDKs, terraform providers, markdown documentation). The determinism makes it useful — API updates propagate continuously from server code, to specifications, then to the SDKs / providers / docs site. There are no breaking changes because the pipeline is deterministic and humans are in control of the API at the start. The code generation itself is just a means to an end : removing boilerplate effort and language differences by driving it from a source of truth (server api routes/types). Continuously generated, it is not debt.

We’ve put a lot of effort into trying to make an LLM agent useful in this context. However giving them control of generated code directly means it’s hard to keep the “no breaking changes”, and “consistency” restrictions that’s needed to make code generation useful.

The trick we’ve landed on to get utility out of an LLM in a code generation task, is to restrict it to manipulating a strictly typed interface document, such that it can only do non-breaking things to code (e.g. adjust comments / descriptions / examples) by making changes through this interface.

In my mind the analagous behaviour would be if the golang checksum database added in license terms that stated "you need to abide by a BSL to use data from this service". What that actually would mean is so nebulous that it feels threatening.

[0] Source: https://registry.terraform.io/v1/providers/airbytehq/airbyte...

[1] Source: https://github.com/airbytehq/terraform-provider-airbyte/tree... gzipped : ~300 resources, ~300 data sources

(NB: in airbyte's case the TF Provider was generated from a ~150Kb OpenAPI spec via https://speakeasyapi.dev: implying docs could be compressed even more)

I'm working on a company https://speakeasyapi.dev/ with the goal helping companies in this ecosystem get great production quality client sdks, terraform providers, cli(s) and all the developer surfaces you may want supported for our API. We also manage the spec and publishing workflow for you so all you have to do is build your API and we'll do the rest.

Feel free to email me at [email protected] or join our slack (https://join.slack.com/t/speakeasy-dev/shared_invite/zt-1cwb...) . We're in open beta and working with a few great companies already and we'd be happy for you to try out the platform for free!

Hi all I am a founding engineer for a API Experience company called Speakeasy - speakeasyapi.dev and we have recently released a Client SDK Generator for APIs using OpenAPI 3.0.X documents (soon to support 3.1). The generator will generate idiomatic Golang SDKs (along with other languages) that feel natural to use, easy to mock, and just work. The generator is free to use and can be run via a standalone golang built CLI with no external dependencies that can be easily installed as a binary or via homebrew (mac & linux). Check it out here https://github.com/speakeasy-api/speakeasy. If you have any questions or want to get in touch to see how Speakeasy can help you improve your APIs, just let me know!

The generator has been battle tested on thousands of APIs and we are sharing the results in our github repo. If you want to try it out on your own, download the CLI or brew install and get started in minutes:

https://github.com/RicoSuter/NSwag

There is no need to be facetious solutions like these exist for many platforms and ecosystems out there.

With best regards.

I'm mostly using it for C# API client generation from backend code - sort of similar to what a tool like NSwag Studio will do. I think NTypewriter has more flexibility though, and having a live view with the VS plugin makes development quick.

NSwag does a wonderful job of generating TypeScript clients from OpenAPI specs. Definitely give it a shot before killing your current setup.

https://github.com/RicoSuter/NSwag (It sucks in any OpenAPI yml, not just ones from Swashbuckle/C#)

I use this https://github.com/RicoSuter/NSwag but it's designed for .Net backends to some extent. But you can use the client generation from the command line or manually with the standalone client app.

Here are three tools that you can use to generate example API requests and responses from OpenAPI specifications. These tools should work well even if your schemas are deeply nested: Nswag (Command Line and GUI): Nswag is a Swagger/OpenAPI toolchain for .NET, TypeScript, and other platforms. It supports code generation, client generation, and API documentation. You can use NswagStudio, which is a graphical interface, or you can use the command line tool called "NSwag.exe" for generating example API requests and responses. GitHub: https://github.com/RicoSuter/NJsonSchema NswagStudio: https://github.com/RicoSuter/NSwag/wiki/NSwagStudio Dredd (Command Line): Dredd is a language-agnostic command-line tool for validating API descriptions against backend implementations. It supports OpenAPI, Swagger, and API Blueprint formats. Dredd can generate example requests and responses and validate whether your API implementation conforms to the API description. GitHub: https://github.com/apiaryio/dredd Documentation: https://dredd.org/en/latest/ Stoplight Studio (GUI): Stoplight Studio is a modern API design and documentation platform that supports OpenAPI and JSON Schema. It allows you to create, edit, and validate OpenAPI specifications and provides a powerful visual interface for generating example API requests and responses. Website: https://stoplight.io/studio/ GitHub: https://github.com/stoplightio/studio These tools should provide you with the ability to generate example API requests and responses from your OpenAPI specifications and handle deeply nested schemas.

I’ve got an ASP.NET Core web API - I integrate NSwag (which I prefer to Swashbuckle - personal preference), run the app locally to generate the actual JSON file. See https://github.com/RicoSuter/NSwag Then I have a Bicep file that creates the API from the OpenAPI specification. Sorry - I don’t do Terraform (most of the Azure samples are of Bicep, but it should be easy to convert).

I have actually found that, but I was hoping for something with more popularity. E.g. this one is for .NET: https://github.com/RicoSuter/NSwag ( you can also generate typescript clients). But I do not want to bring in the dependency to another language, if possible.