rajt/src/validator.ts

A serverless bundler layer, fully typed for AWS Lambda (Node.js and LLRT) and Cloudflare Workers.

import { ZodObject } from 'zod'
import { validator } from 'hono-openapi'
import response from './response'
import type {
  Rule, Rules,
  ValidationTargets,
} from './types'

export default class $Validator {
  private static cache = new Map<string, (schema: ZodObject<any>) => Rule>()

  private static createRule<T extends keyof ValidationTargets>(
    target: T,
    schema: ZodObject<any>
  ): Rule {
    return {
      target,
      schema,
      eTarget: 'fieldErrors'
    }
  }

  private static fn<T extends keyof ValidationTargets>(target: T) {
    if (this.cache.has(target))
      return this.cache.get(target)

    const fn = (schema: ZodObject<any>) => this.createRule(target, schema)
    this.cache.set(target, fn)
    return fn
  }

  static readonly json = $Validator.fn('json')!
  static readonly form = $Validator.fn('form')!
  static readonly query = $Validator.fn('query')!
  static readonly param = $Validator.fn('param')!
  static readonly header = $Validator.fn('header')!
  static readonly cookie = $Validator.fn('cookie')!

  static parse(rules: Rules): Function[] {
    return (Array.isArray(rules) ? rules : [rules]) // @ts-ignore
      .flatMap(rule => validator(rule.target, rule.schema, (result, c) => {
        if (!result.success) // @ts-ignore
          return response.badRequest(result.error)
      }))
  }
}