A React hook for calling Next.js Server Actions from client components

client.tsx

'use client'

import { test } from './server'
import { useServerAction } from './hook'

export default function Home() {
  const { data, loading, error, execute: testAction } = useServerAction(test)

  if (loading) return <div>Loading...</div>
  if (error) return <div>Error: {error.message}</div>

  return (
    <>
      <form action={testAction}>
        <input type="text" name='name' />
        <button type="submit">Submit</button>
      </form>
      <div>{data}</div>
    </>
  )
}

server.tsx

'use server'

export async function test(form: FormData) {
  const name = form.get('name')
  return name?.toString()
}

useServerAction.ts

import { useState } from 'react'

type AsyncFunction = (...args: any) => Promise<any>

export function useServerAction<T extends AsyncFunction>(action: T) {
  const [loading, setLoading] = useState(false)
  const [error, setError] = useState<Error | null | undefined>(null)
  const [data, setData] = useState<Awaited<ReturnType<T>> | null | undefined>(null)

  async function execute (...payload: Parameters<T>) {
    setLoading(true)
    setError(null)
    setData(null)

    try {
      const res = await action(payload)
      setData(res)
    } catch (e: any) {
      setError(e)
    }

    setLoading(false)
  }

  return {
    data,
    loading,
    error,
    execute
   }
}

I have a question. If you execute revalidatePath in the action, does await action(payload) wait for the new data (e.g. if you reload a list)?

This isn't explained in the docs, but I think it doesn't. I think that's why it recommends wrapping it in startTransition, which presumably somehow waits for it.

I have had some cases where there's a mismatch between my loading state and the timing where the data is updated (which is clear after using a sleep in the page that renders the new data).

@ChrisVilches good question. I'm not an expert, so maybe ask @dan_abramov on twitter

I think it's basically the same as this? https://github.com/pingdotgg/zact

This package is good. Great work by @t3dotgg

formdata validation options, something like this???

import { useState } from 'react';
import { z } from 'zod';
function formDataToObject(formData: FormData): { [key: string]: any } {
	const object: { [key: string]: any } = {};
	formData.forEach((value, key) => {
		if (!object.hasOwnProperty(key)) {
			object[key] = value;
		} else if (Array.isArray(object[key])) {
			object[key].push(value);
		} else {
			object[key] = [object[key], value];
		}
	});
	return object;
}

type AsyncFunction = (...args: any) => Promise<any>;
export function getPayloadSchema() {
	return z.object({
		// Define your payload schema using Zod's validation functions
		// For example:
		name: z.string().min(3).max(20)
	});
}

export function useServerAction<T extends AsyncFunction>(action: T, validator: z.Schema) {
	const [loading, setLoading] = useState(false);
	const [error, setError] = useState<Error | null | undefined>(null);
	const [data, setData] = useState<Awaited<ReturnType<T>> | null | undefined>(null);

	async function execute(payload: FormData) {
		setLoading(true);
		setError(null);
		setData(null);

		try {
			// Validate the payload using the provided Zod schema
			const objectData = formDataToObject(payload);

			const validatedPayload = validator.parse(objectData);
			const res = await action(validatedPayload);
			setData(res);
		} catch (e: any) {
			setError(e);
		}

		setLoading(false);
	}

	return {
		data,
		loading,
		error,
		execute
	};
}

'use client';

import { useServerAction } from '@/lib/useServerAction';
import { test } from './action';
import { z } from 'zod';

export default function Form() {
	const {
		data,
		loading,
		error,
		execute: testAction
	} = useServerAction(
		test,
		z.object({
			name: z.string().min(3).max(20)
		})
	);
	if (loading) return <div>Loading...</div>;
	if (error) return <div>Error: {error.message}</div>;

	return (
		<form action={testAction} className='flex flex-col justify-center items-center h-full'>
			<input placeholder='Enter a value' name='name' />
			<button type='submit'>Add</button>
			<div>{JSON.stringify(data, null, 2)}</div>
		</form>
	);
}

'use server';
export async function test({ name }: { name: string }) {
	
	return name ;
}

the payload formData is most likely empyt.