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Validator in js

Hello world!!
I'm searching about validator in js and ts. So, I'm gonna write about my summary and conclution.!!



Package Feature Merit Demerit Link
Zod TypeScript-first schema validation with static type inference Method chaining and easy to get ts type Newer package
joi This is almost same to zod Have many plugins Doesn't support static type inference
Yup This is almost same to zod Have many plugins Missing some feature, function, deep object, promise... ...
class-validator Validate class properties Have many features Code isn't clean
ajv Validate by json scheme Enable to share schem to other languages Not supported typescript


If you don't validate by class

I recommand you zod.

If you want to use decorator for validation

I don't recommand you class-validator, instead of it, I recommand you some plugins.

For example, joiful. This is joi plugin.


// In typescript
import { z } from 'zod'

const userScheme = z.object({
    username: z.string(),
    email: z.string().email()
type User = z.infer<typeof userScheme>

const data: User = {
    username: 'Takashi',
    email: 'not email'

// This code will throw validation error!!
const validated = userScheme.parse(data)

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This post blew up on DEV in 2020:

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🚀⚙️ JavaScript Visualized: the JavaScript Engine

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Happy coding!