README.md

@pyncz/zod-key-mapper

🗝️ Transform keys of zod object schemas

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Installation

Just install it with your favourite package manager:

pnpm install @pyncz/zod-key-mapper

Usage

Let's say, you use a 3rd party API to fetch some data. You want to parse and transform it with zod for further usage, including some operations with keys, e.g. mapping keys from snake_case to camelCase, or even change some confusing field names into something more convenient.

@pyncz/zod-key-mapper provides a convenient way to transform keys:

import { z } from 'zod'
import { mapped } from '@pyncz/zod-key-mapper'

const schema = mapped(z.object({
  snake_case_field: z.string(),
  foo: z.number(),
  bar: z.number(),
}), { snake_case_field: 'weRespectCamelsHere' })

console.log(schema.parse({ snake_case_field: 'hey', foo: 69, bar: 420 }))
// > { weRespectCamelsHere: 'hey', foo: 69, bar: 420 }

You can map multiple keys:

const schema = mapped(z.object({
  key1: z.string(),
  key2: z.number(),
  key3: z.number(),
}), { key1: 'key1mod', key2: 'key2mod' })

console.log(schema.parse({ key1: 'hey', key2: 69, key3: 420 }))
// > { key1mod: 'hey', key2mod: 69, key3: 420 }

Or you can map the schema key by key:

const schema = mapped(mapped(z.object({
  key1: z.string(),
  key2: z.number(),
  key3: z.number(),
}), { key1: 'key1mod' }), { key2: 'key2mod' })

console.log(schema.parse({ key1: 'hey', key2: 69, key3: 420 }))
// > { key1mod: 'hey', key2mod: 69, key3: 420 }

Arguments

• schema - your Zod type
• keysMap - a readonly object with keys you want to rename as keys, and corresponding new keys as values.

What's up with other keys operations?

"What if I want to add or remove keys, not just transform them?"

Well, you should use pick / omit methods zod provides out of the box, before mapping:

const schema = mapped(z.object({
  key1: z.string(),
  key2: z.number(),
  key3: z.number(),
}).pick({ key1: true }), { key1: 'key1mod' })

console.log(schema.parse({ key1: 'hey', key2: 69, key3: 420 }))
// > { key1mod: 'hey' }