@jcoreio/zod-forms

A more seamless way to build React forms from Zod schemas

Features

• 100% typesafe - Fully typechecked paths, input and output types for deeply nested fields
• Supports z.string().optional(), z.string().nullable(), z.number() etc in inputs out of the box
• Interprets blank inputs as undefined or null by default, depending on what the field schema accepts
• Normalizes inputs on blur by default (e.g. with z.string().blur() you'll see the trim on blur)
• Supports Zod schemas with different input and output types (as long as you use zod-invertible to specify how to format from output back to input)
• Allows you to programmatically set either input or output values
• Each step of a wizard form can declare its own submit handler independent from the enclosing <form> element. This enables animated transitions between steps without a separate <form>s or submit button for each step.

Limitations

• Designed specifically for Zod and React only
• Not currently focused on high performance/large form state like final-form or react-hooks-form
• No async validate outside of submit right now

Quickstart

Installation

pnpm i @jcoreio/zod-forms

or if you're using npm:

npm i --save @jcoreio/zod-forms

Create a form schema

In this example, we'll have a url field that must be a valid URL. Using .trim() ensures that the submitted value will be trimmed. The displayed value will also be trimmed whenever the field is blurred.

import z from 'zod'

const schema = z.object({
  url: z.string().trim().url(),
})

Create a form

import { createZodForm } from '@jcoreio/zod-form'

const {
  FormProvider,
  // all of the following hooks can also be imported from '@jcoreio/zod-form',
  // but the ones returned from `createZodForm` are already bound to the schema type
  useInitialize,
  useSubmit,
  useFormStatus,
  useHtmlField,
} = createZodForm({ schema })

Create a field component

import { FieldPathForRawValue } from '@jcoreio/zod-form'

function FormInput({
  field,
  type,
  ...props
}: Omit<React.InputHTMLAttributes<HTMLInputElement>, 'type'> & {
  type: HTMLInputTypeAttribute
  // This ensures that only fields that accept string, null or undefined
  // as input can be passed to <FormInput>
  field: FieldPathForRawValue<string | null | undefined>
}) {
  // This hook is designed to provide the smoothest integration with simple <input>s.
  const { input, meta } = useHtmlField({ field, type })

  const inputRef = React.createRef<HTMLInputElement>()
  const error = meta.touched || meta.submitFailed ? meta.error : undefined
  React.useEffect(() => {
    inputRef.current?.setCustomValidity(error || '')
  }, [error])

  return (
    <input
      {...props}
      // the `input` props from `useHtmlField` are designed to be spread here
      {...input}
      ref={inputRef}
    />
  )
}

Create the form component

function MyForm() {
  return (
    // <FormProvider> wraps <MyFormContent> in a React Context through which the
    // hooks and fields access form state
    <FormProvider>
      <MyFormContent />
    </FormProvider>
  )
}

function MyFormContent() {
  // This hook initializes the form with the given values.
  // The second argument is a dependency array -- the form will be reinitialized
  // if any of the dependencies change, similar to React.useEffect.
  useInitialize({ values: { url: 'http://localhost' } }, [])

  // This hook sets your submit handler code, and returns an onSubmit handler to
  // pass to a <form>
  const onSubmit = useSubmit({
    onSubmit: async ({ url }) => {
      alert(`Submitted! url value: ${url}`)
    },
  })

  const { submitting, pristine } = useFormStatus()

  return (
    <form onSubmit={onSubmit}>
      <FormInput
        // this is how we bind <FormInput> to the `url` field
        field={myForm.get('url')}
        type="text"
        placeholder="URL"
      />
      <button disabled={pristine || submitting} type="submit">
        submit
      </button>
    </form>
  )
}