@kafkats/flow-codec-zod

Zod schema validation codecs for @kafkats/client and @kafkats/flow.

Features

• Runtime Validation - Validate messages at encode and decode
• Type Inference - TypeScript types from Zod schemas
• Error Messages - Detailed validation error reporting
• Zero Configuration - Just pass your Zod schema

Installation

pnpm add @kafkats/flow-codec-zod zod

Quick Example

import { flow, topic } from '@kafkats/flow'
import { string } from '@kafkats/client'
import { zodCodec } from '@kafkats/flow-codec-zod'
import { z } from 'zod'

// Define schema
const UserSchema = z.object({
	id: z.string().uuid(),
	email: z.string().email(),
	age: z.number().min(0).max(150),
	role: z.enum(['admin', 'user', 'guest']),
})

// Create codec from schema
const userCodec = zodCodec(UserSchema)

// Use in topic definition
const users = topic('users', {
	key: string(),
	value: userCodec,
})

// Type is inferred from schema
type User = z.infer<typeof UserSchema>

How It Works

The codec:

1. On encode: Validates the value, then JSON stringifies
2. On decode: JSON parses, then validates the result

// This will throw on invalid data
userCodec.encode({ id: 'not-a-uuid', email: 'invalid', age: -5, role: 'unknown' })
// ZodError: invalid_string at id, invalid_string at email, ...

// Valid data works
userCodec.encode({ id: '123e4567-e89b-12d3-a456-426614174000', email: 'a@b.com', age: 25, role: 'user' })
// Buffer containing JSON

Next Steps

• Usage Guide - Detailed usage patterns