Emanuel Suriano
Jul 7, 2020 ⋅ 9 min read

Dynamic type validation in TypeScript

Emanuel Suriano Hi 👋 I build stuff with JavaScript 💻 Once a month I write an article ✍️ and sometimes I give talks 💬

Recent posts:

Handling File Uploads In Next.js Using UploadThing

Handling file uploads in Next.js using UploadThing

Manage file uploads in your Next.js app using UploadThing, a file upload tool to be used in full-stack TypeScript applications.

Jude Miracle
Jun 21, 2024 ⋅ 15 min read
Exploring Advanced Support For Vite 5 In Storybook 8

Exploring advanced support for Vite 5 in Storybook 8

Explore the latest updates in Storybook 8, focusing on its improved support for Vite 5 as a build tool.

Will Soares
Jun 20, 2024 ⋅ 5 min read
Using Next Js With React Suspense To Create A Loading Component

Using Next.js with Suspense to create a loading component

Next.js 13 introduced some new features like support for Suspense, a React feature that lets you delay displaying a component until the children have finished loading.

Suraj Vishwakarma
Jun 19, 2024 ⋅ 9 min read
Exploring Angular 18's Redirectcommand Class And Let Block

Exploring Angular 18’s RedirectCommand class and @let block

Angular’s latest update brings greater control over redirects and the ability to define and assign variables within the template.

Lewis Cianci
Jun 19, 2024 ⋅ 6 min read
View all posts

3 Replies to "Dynamic type validation in TypeScript"

  1. In frontend we are very good in making stuff ultra complex 🙁

    Your “typescript isse” is not a typescript issue, because you simply dont type your service. For that you can use autogenerating their DTO into types, libs like ‘dtsgenerator’ just need the open api spec of the resource api. Problem solved. Just automate more, write less code and dont inject another dep which is only overhead.

  2. Nice post,

    I’m the author of this project [typescript-field-validation](https://www.npmjs.com/package/typescript-field-validation) which aims to solve (some of) these issues. I’ve taken a different approach, rather than validate the incoming data against an openAPI schema, simply constrain the fields you need to use as non nullable and assume the value must be the resulting type as defined in the specification. Yes it defines new syntax, but it’s just dot notation and the same array syntax we already use in Typescript, no big deal. Compared to some of the above mentioned packages, this simple tool might be all you need to wrangle those enormous auto-generated schema types into constrained types with non optional and non nullable fields. At a minimum performing these checks upfront could help clean up hundreds of null checks peppered throughout many code bases.

  3. I like the approach,

    My case is little bit different I generate all of the types from the open api.This is huge help and covers generates all of the necessary types. How ever, we have a form of which data needs to be eventually typed to RestCreateType. With dynamic validation I can take RestCreateType generate validation schema and avoid additional work and lower code dependency on generated types.

Leave a Reply