Astro Actions in Astro

// src/actions/index.ts
import { defineAction } from 'astro:actions'
import { z } from 'astro:schema'

export const server = {
  createComment: defineAction({
    accept: 'form',
    input: z.object({
      postId: z.string(),
      body: z.string().min(1).max(2000),
    }),
    handler: async ({ postId, body }, { cookies }) => {
      const user = cookies.get('userId')?.value
      if (!user) throw new Error('Not signed in')
      return db.comment.create({ data: { postId, body, userId: user } })
    },
  }),
}

// Use from a client component
<form method="POST" action={actions.createComment}>
  <input name="postId" value={post.id} hidden />
  <textarea name="body"></textarea>
  <button>Comment</button>
</form>