fastify-swagger VS json-schema-to-ts

With Speakeasy, you can create client SDKs based on an OpenAPI specification. Fastify ships with the @fastify/swagger plugin, which provides convenient shortcuts for generating good OpenAPI specifications. We'll start this tutorial by registering @fastify/swagger in a Fastify project to generate a spec.

First let’s get our current OpenAPI specification out of Fastify and onto the file system. If you have not added the https://github.com/fastify/fastify-swagger plugin first go do that. Then use this simple script I called generate-spec.ts to write your OpenAPI specification to the filesystem.

The fastify-swagger docs has an example https://github.com/fastify/fastify-swagger

@fastify/swagger is a fastify plugin to serve a Swagger UI, using Swagger (OpenAPI v2) or OpenAPI v3 schemas automatically generated from your route schemas, or from an existing Swagger/OpenAPI schema.

On the Node.js framework side of things, Fastify has support for Swagger with the fastify-swagger plugin.

With this approach, backend can be any programming languages that support OpenAPI or Swagger. Personally, I use fastify-swagger; but I can also be things like Python's FastAPI or Golang's Gin/Buffalo/Native.

JSON Schema To TS

// First create a general "post" schema // Shared Schema export const postSchema = { $id: 'post', type: 'object', properties: { id: { type: 'number' }, title: { type: 'string' }, published: { type: 'boolean' }, content: { type: 'string' }, tags: { type: 'array', items: { type: 'string' } }, deleted: { type: 'boolean' } }, required: ['title', 'published', 'content', 'tags', 'deleted'] } as const // We don't need to create a separate "bodySchema". // But directly infer type from postSchema export type Body = FromSchema // Reply Schema // Check https://www.fastify.io/docs/latest/Reference/Validation-and-Serialization/#adding-a-shared-schema const replySchema = { type: 'object', properties: { posts: { type: 'array', items: { $ref: 'post#' } } }, additionalProperties: false } as const // Check https://github.com/ThomasAribart/json-schema-to-ts#references export type Reply = FromSchema< typeof replySchema, { references: [typeof postSchema] } > // Also make ReplyNotFound reusable for future use export const postNotFoundSchema = { $id: 'postNotFound', // add $id here type: 'object', required: ['error'], properties: { error: { type: 'string' } }, additionalProperties: false } as const export type PostNotFound = FromSchema

json-schema-to-ts comes to the rescue. 💪

https://github.com/ThomasAribart/json-schema-to-ts - Infers TS Types from raw JSON Schema object literals you embed in your code.

Fonte: https://github.com/ThomasAribart/json-schema-to-ts