Forma-JS (Remix.run's Form component inspired library)

Remix.run has a super cool Form component which almost eliminate the usage of states. And also gracefully cancel the simultaneous form requests. This library is inspired by the remix.run's Form component with a bit more features that might be necessary in non remix projects.

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Announcement!

In Mar 23rd, 2022(I'm from South-east Asia so timeline might be a bit different for you ⏱), remix announced that next react-router release will also be included with remix's route based data fetching, Form, useFetcher and other cool features. Therefore, this library will be archived after a few weeks of react-router releasing with these cool features. Since this library's purpose is to kind of mimic remix's Form component and useFetcher hook, it will not be necessary anymore when react-router releases with these features. Hope you have a smooth transition to remix or react-router in new release.

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Disclaimer

This library is not a replacement of the remix.run's Form component. It is to help your old projects migrate to remix.run by familiarizing you team members with the remix's similar Form component.

This library also does not mimic the remix.run's Form component which is bind with route transitions and so on. This library is more similar to remix.run's useFetcher since this uses fetch request and provide component level states.

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Fallback Support

If you want your browser to fallback the fetch request, you need to avoid using encType="application/json" and method="graphql" in your form. These two features are fancy add-on features that are not supported by the browser without enabling JavaScript.

IN SUMMARY: If you need to support the use-case of users disabling JavaScript on their browsers, you need to avoid using encType="application/json" and method="graphql" in your form. Since these two features only work when JavaScript is enabled.

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Breaking Changes

• ConfigProvider component is deprecated starting from v1.3.0
  • After asking for an opinion about this library from Kent C. Dodds on his live-stream, my opinion align with his explanation. Instead of using ConfigProvider, we should use constant variables like .env or config.js to store the configuration. And then use it as action baseUrl should be more declarative.

---

Installation

npm i @forma-js/react

# OR

yarn add @forma-js/react

---

Usage

Basic Form

import { Form } from '@forma-js/react'

/**
 * in your project you should store this url in `.env` file
 * or separate `config.js` file and import it
 */
const baseUrl = 'https://mysecurebackend.com/api'

function LoginForm() {
  return (
    <Form method="post" action={`${baseUrl}/login`}>
      {() => (
        <div>
          <input name="email" type="email" />
          <input name="password" type="password" />
          <button type="submit">Login</button>
        </div>
      )}
    </Form>
  )
}

---

Global Config Provider (deprecated)

App.tsx

import { ConfigProvider } from '@forma-js/react'
import { CreateUserForm } from './CreateUserForm'

export function App() {
  return (
    <ConfigProvider
      baseUrl="http://localhost:4000/api"
      method="post"
      encType="application/json"
    >
      <CreateUserForm />
    </ConfigProvider>
  )
}

CreateUserForm.tsx

import { Form } from '@forma-js/react'

export function CreateUserForm() {
  return (
    <Form action="/users">
      {() => (
        <div>
          <input name="name" type="text" />
          <input name="email" type="email" />
          <button type="submit">Create New User</button>
        </div>
      )}
    </Form>
  )
}

---

Pending State

import { Form } from '@forma-js/react'

function CreateUserForm() {
  return (
    <Form action="/users">
      {({ transition }) => (
        <div>
          <input name="name" type="text" />
          <input name="email" type="email" />
          <button
            type="submit"
            aria-disabled={transition.state === 'submitting'}
          >
            {transition.state === 'submitting'
              ? 'Creating ...'
              : 'Create New User'}
          </button>
        </div>
      )}
    </Form>
  )
}

---

Cancelable Form

import { Form } from '@forma-js/react'

function CreateUserForm() {
  return (
    <Form action="/users">
      {({ abort, transition }) => (
        <div>
          <input name="name" type="text" />
          <input name="email" type="email" />
          {transition.state === 'submitting' && (
            <button type="button" onClick={abort}>
              Cancel
            </button>
          )}
          <button type="submit">Create New User</button>
        </div>
      )}
    </Form>
  )
}

---

Form with Error

import { Form } from '@forma-js/react'

function CreateUserForm() {
  return (
    <Form action="/users">
      {({ error }) => (
        <div>
          {error?.message && <div>{error.message}</div>}
          <input name="name" type="text" />
          <input name="email" type="email" />
          <button type="submit">Create New User</button>
        </div>
      )}
    </Form>
  )
}

---

Form with Success

import { Form } from '@forma-js/react'

function CreateUserForm() {
  return (
    <Form action="/users">
      {({ status, data }) => (
        <div>
          {status === 200 && <div>{data.message}</div>}
          <input name="name" type="text" />
          <input name="email" type="email" />
          <button type="submit">Create New User</button>
        </div>
      )}
    </Form>
  )
}

---

Hook Form

import { useForm } from '@forma-js/react'

const baseUrl = 'https://mysecurebackend.com/api'

function CreateUserForm() {
  /**
   * transform and headers need to Memoize in hook form.
   * otherwise, it will trigger re-render infinitely.
   * if you don't want to memoize them, you can declare them outside of the react component.
   */
  const transform = React.useCallback(
    (data) => ({ ...data, age: Number(data.age) }),
    [],
  )
  const headers = React.useMemo(() => ({ authorization: 'Bearer 123' }), [])

  const createUserForm = useForm({
    action: `${baseUrl}/users`,
    method: 'post',
    encType: 'application/json',
    transform,
    headers,
  })

  return (
    <form {...createUserForm.getFormProps()}>
      <input name="name" type="text" />
      <input name="email" type="email" />
      <input name="age" type="number" />
      <button
        type="submit"
        aria-disabled={createUserForm.transition.state === 'submitting'}
      >
        Create New User
      </button>
    </form>
  )
}

---

GraphQL Form

import { Form } from '@forma-js/react'

const baseUrl = 'https://mysecurebackend.com/api'

function CreateUserForm() {
  return (
    <Form
      method="graphql"
      action={`${baseUrl}/users`}
      query={`
        mutation CreateUser($name: String!, $email: String!) {
          createUser(name: $name, email: $email) {
            id
            name
            email
          }
        }
      `}
    >
      {() => (
        <div>
          <input name="name" type="text" />
          <input name="email" type="email" />
          <button type="submit">Create New User</button>
        </div>
      )}
    </Form>
  )
}

---

Get Form Data

import { Form } from '@forma-js/react'

function CreateUserForm() {
  return (
    <Form action="/users">
      {({ transition }) => (
        <div>
          <input name="name" type="text" />
          <input name="email" type="email" />

          <button
            name="_action"
            value="update"
            type="submit"
            aria-disabled={transition.state === 'submitting'}
          >
            {transition.state === 'submitting' &&
            transition.formData.get('_action') === 'update'
              ? 'Updating ...'
              : 'Update User'}
          </button>

          <button
            name="_action"
            value="create"
            type="submit"
            aria-disabled={transition.state === 'submitting'}
          >
            {transition.state === 'submitting' &&
            transition.formData.get('_action') === 'create'
              ? 'Creating ...'
              : 'Create New User'}
          </button>
        </div>
      )}
    </Form>
  )
}

---

Post Form Data with Transform (graphql and application/json only)

import { Form } from '@forma-js/react'

function CreateUserForm() {
  return (
    <Form
      action="/users"
      encType="application/json"
      transform={(data) => ({ ...data, age: Number(data.age) })}
    >
      {() => (
        <div>
          <input name="name" type="text" />
          <input name="age" type="number" />
          <button type="submit">Submit</button>
        </div>
      )}
    </Form>
  )
}

---

Life Cycle

import { Form } from '@forma-js/react'

function CreateUserForm() {
  return (
    <Form
      action="/users"
      hook={{
        beforeRequest(init) {
          console.log('beforeRequest', init)
        },
        afterRequest() {
          console.log('afterRequest')
        },
        onSuccess(response) {
          console.log('onSuccess', response)
        },
        onError(error) {
          console.log('onError', error)
        },
        onAbort() {
          console.log('onAbort')
        },
        onCatchError(e) {
          console.log('onCatchError', e)
        },
      }}
    >
      {({ transition }) => (
        <div>
          <input name="name" type="text" />
          <input name="email" type="email" />
          <button
            type="submit"
            aria-disabled={transition.state === 'submitting'}
          >
            Create New User
          </button>
        </div>
      )}
    </Form>
  )
}

---

API

function Form<DataType, ErrorType>({
  method,
  action,
  encType,
  query,
  hook,
  body,
  includeSubmitValue,
  children,
}: FormProps<DataType, ErrorType> &
  Omit<
    React.FormHTMLAttributes<HTMLFormElement>,
    'method' | 'encType' | 'action'
  >): JSX.Element

function useForm<DataType, ErrorType>(
  config: FormProps<DataType, ErrorType>,
): UseFormReturnType<DataType, ErrorType>

/** @deprecated */
const ConfigProvider: React.FC<Config>

Types

type Method = 'get' | 'post' | 'put' | 'delete' | 'patch' | 'graphql'

type EncType =
  | 'multipart/form-data'
  | 'application/json'
  | 'application/x-www-form-urlencoded'

type TransitionState = 'idle' | 'submitting' | 'error' | 'catch-error'

interface Transition {
  state: TransitionState
  formData: FormData
}

type ResponseParam<DataType> = Response & { data: DataType }

type LifeCycleFuncs<DataType, ErrorType> = {
  /**
   * Called right before making fetch request, after generating request init.
   * RequestInit object is passed as argument so that it can be modified before
   * making the request. All the options except `signal` is mutable for the RequestInit.
   */
  beforeRequest?: (init: Omit<RequestInit, 'signal'>) => void
  /**
   * Called after fetch request whether it's `failed` or `success`.
   * Cannot access to any object.
   */
  afterRequest?: () => void
  /**
   * Called when `response.ok` is `true`.
   * Response object is passed as argument.
   */
  onSuccess?: (res: ResponseParam<DataType>) => void
  /**
   * Called when `response.ok` is `false`.
   * Response object is passed as argument.
   */
  onError?: (res: ResponseParam<ErrorType>) => void
  /**
   * Called on catch handler.
   * Error object is passed as argument.
   */
  onCatchError?: (e: any) => void
  /**
   * Called after fetch request is aborted.
   * Cannot access to any object.
   */
  afterAbort?: () => void
}

type ChildrenProps<DataType, ErrorType> = {
  data: DataType | null
  error: ErrorType | null
  status: number
  transition: Transition
  abort: () => void
}

type FormProps<DataType, ErrorType> = {
  useBaseConfig?: boolean
  action: string
  method: Method
  encType?: EncType
  query?: string
  body?: any
  hook?: LifeCycleFuncs<DataType, ErrorType>
  includeSubmitValue?: boolean
  transform?: (data: { [key: string]: any }) => any
  children: (props: ChildrenProps<DataType, ErrorType>) => React.ReactNode
}

type UseFormReturnType<DataType, ErrorType> = ChildrenProps<
  DataType,
  ErrorType
> & {
  ref: React.MutableRefObject<HTMLFormElement | null>
  onSubmit: (e: React.FormEvent<HTMLFormElement>) => void
}