Server Actions in Next.js Complete Guide

'use server';

export async function createPost(formData: FormData) {
  const title = formData.get('title');
  await db.posts.create({ title });
  revalidatePath('/posts');
}

import { createPost } from './actions';

function NewPostForm() {
  const formAction = useFormState(createPost, null);

  return (
    <form action={formAction}>
      <input name="title" />
      <button type="submit">Create</button>
    </form>
  );
}