ts-simple-type VS swagger-ui

We use an internal validator library that we infer request types from. It’s similar to Zod (but also predates it by a year).

I’ve also spent some time on a Typescript type to X compiler. My first prototype is open source and targets Thrift, Proto3, Python, and JSON schema: https://github.com/justjake/ts-simple-type/tree/main/src/com...

I’m not happy with the design decision in that codebase to try to “simplify” Typescript types before compiling, and probably won’t continue that implementation, but we have a few internal code generators that consume TS types and output test data builders and model clases we use in production.

After some frustration with the TypeScript schema library ecosystem, I've decided that I'd prefer to declare my types using TypeScript's excellent type syntax, so I can take advantage of generics, mapped types, etc. Then, I'll take those TypeScript types and compile them to whatever alternative schema format I need.

There are many libraries that claim to convert your Typescript types to other formats, such as ts-json-schema-generator, ts-to-zod, or typeconv/core-types-ts. These libraries work by interpreting the Typescript AST, essentially re-implementing a bare-bones type system from scratch. Most do not support advanced Typescript features like generic application, mapped types, or string literal types. So, what's the point? To avoid those limitations, I use Typescript's first-party ts.TypeChecker API to analyze types, and an existing library called ts-simple-type (which I've forked) to convert from ts.Type to a more usable intermediate format. Then, I recurse over the intermediate format and emit "AST nodes". It's pretty simple, but seems promising.

So far, I have compilers from TypeScript type to Python 3 and Thrift. But I plan to add OpenAPI/JSONSchema, Protobuf (Proto3), Kotlin, Swift, and maybe Zod and Avro. Each target language is around ~300 LoC so they're pretty easy to put together.

Repo: https://github.com/justjake/ts-simple-type

Compiler input and output: https://github.com/justjake/ts-simple-type/blob/jake--compil...

Thrift compiler: https://github.com/justjake/ts-simple-type/blob/jake--compil...

Python compiler: https://github.com/justjake/ts-simple-type/blob/jake--compil...

Swagger is a fantastic open-source toolset that's perfect for developing and describing RESTful APIs. It offers you a user-friendly interface to understand a service's capabilities without needing to dig into the code. It even provides a way for you to interact directly with the API, which means you get to test its functionality.

The API had an OpenAPI endpoint built with Swagger where I could download a JSON specification file for the API.

Swagger is a widely used tool for documenting and testing APIs.

Swagger is an open-source software framework that implements the OpenAPI Specification—an API description format for REST APIs. The OpenAPI Specification defines a standard, language-agnostic interface to HTTP APIs, enabling both humans and computers to discover and understand the capabilities of the API.

Mocking and Testing: Once the API design is complete, developers create mock APIs to simulate the behavior of the actual services. This early testing phase helps identify any issues or mismatches between design and implementation before substantial development efforts are invested. Tools like Postman or Swagger are invaluable for API testing and validation.

import fp from "fastify-plugin"; import swagger from "@fastify/swagger"; export default fp(async (fastify) => { fastify.register(swagger, { openapi: { info: { tags: [ { name: "drinks", description: "Drink-related endpoints", externalDocs: { description: "Find out more", url: "http://swagger.io", }, }, ], }, }, }); });

A very requested feature for Sharkio was the auto-generation of OpenAPI documentation using the recorded HTTP requests - to create standardized documentation.

Automation QA is a lot of the same duties as manual QA, but instead of writing and executing the test plans manually, we create and update automated tests that can run those validations programmatically, for example by using Selenium to automatically fill out and submit forms for a web application, or using Postman and/or Swagger to generate an API conversation test.