Validasi skema dengan zod & inferensi ke TS

Pendahuluan

Skema dan inferensi

import { z } from "zod"

export const userSchema = z.object({
  id: z.string().regex(/^u_[a-z0-9]+$/),
  name: z.string().min(1),
  age: z.number().int().nonnegative().optional()
})

export type User = z.infer<typeof userSchema>

// Reuse `User` across handlers, services, and tests

safeParse dalam penangan

import { Request, Response } from "express"
import { userSchema, User } from "./schema"

export function createUser(req: Request<{}, User, unknown>, res: Response<User | { error: string; issues?: unknown }>) {
  const parsed = userSchema.safeParse(req.body)
  if (!parsed.success) {
    return res.status(400).json({ error: "Invalid body", issues: parsed.error.format() })
  }
  const user = parsed.data
  return res.status(201).json(user)
}

Pembantu middleware

import { z } from "zod"
import { Request, Response, NextFunction } from "express"

export function validateBody<T extends z.ZodTypeAny>(schema: T) {
  return (req: Request, res: Response, next: NextFunction) => {
    const r = schema.safeParse(req.body)
    if (!r.success) {
      return res.status(400).json({ error: "Invalid body", issues: r.error.format() })
    }
    req.body = r.data
    next()
  }
}

Koersi & refine

import { z } from "zod"

const signupSchema = z.object({
  email: z.string().email(),
  age: z.coerce.number().int().gte(13),
  role: z.enum(["user", "admin"]).default("user")
}).refine(v => v.role !== "admin" || v.age >= 18, { message: "admin must be adult" })

export type Signup = z.infer<typeof signupSchema>

// Coercion allows numbers in strings; refine adds cross-field rules

Kiat kesalahan

Pemeriksaan inferensi zod

Ringkasan