# Next.js

> Submit from a Next.js App Router client component, or through a server action with a secret key.

There are two good ways to submit from Next.js. Post from the browser in a client component, which keeps each visitor's own IP for rate limits and works with every spam check. Or post from a server action, which keeps the form working without JavaScript.

|   | Client component | Server action |
| --- | --- | --- |
| Works without JavaScript | No | Yes |
| Rate limits count | Each visitor | Your server's IP |
| Ikiform human check | Use `challenge` from the SDK | Skipped with a secret key |
| Allowed domains | Checked against the browser's origin | Skipped with a secret key |
| Needs a secret key | No | Yes |

## Install the SDK

`Terminal`:

```bash
npm install @ikiform/sdk
```

The SDK is optional. Everything below also works with `fetch`; see [JavaScript and fetch](https://ikiform.com/docs/frameworks.md).

## From a client component

`app/contact/contact-form.tsx`:

```tsx
"use client";

import { submit } from "@ikiform/sdk";
import { useState } from "react";

type Status = "idle" | "sending" | "sent" | "error";

export function ContactForm() {
  const [status, setStatus] = useState<Status>("idle");
  const [errors, setErrors] = useState<Record<string, string[]>>({});
  const [message, setMessage] = useState("");

  async function onSubmit(event: React.FormEvent<HTMLFormElement>) {
    event.preventDefault();
    setStatus("sending");
    const result = await submit("frm_xxxxxxxxxxxxxxxx", new FormData(event.currentTarget));
    if (result.ok) return setStatus("sent");
    setErrors(result.error.fields ?? {});
    setMessage(result.error.message);
    setStatus("error");
  }

  if (status === "sent") return <p>Thanks, we got it.</p>;

  return (
    <form onSubmit={onSubmit} noValidate>
      <label htmlFor="email">Email</label>
      <input id="email" name="email" type="email" required aria-invalid={Boolean(errors.email)} />
      {errors.email ? <p>{errors.email[0]}</p> : null}
      <label htmlFor="message">Message</label>
      <textarea id="message" name="message" />
      <input name="_gotcha" type="text" tabIndex={-1} autoComplete="off" hidden />
      {status === "error" && !Object.keys(errors).length ? <p role="alert">{message}</p> : null}
      <button disabled={status === "sending"}>{status === "sending" ? "Sending" : "Send"}</button>
    </form>
  );
}
```

- `submit` never throws. It resolves to `{ ok: true, id }` or `{ ok: false, error, status, requestId }`.
- `error.fields` maps field ids to messages when the form has [fields](https://ikiform.com/docs/fields.md) defined.
- Render the component from any server component page, for example `app/contact/page.tsx`.

### With the Ikiform human check

If the form's spam check is **Ikiform**, get a token right before each submit. `challenge` mounts a small ikiform.com frame that stays invisible unless Turnstile needs a click.

`contact-form.tsx`:

```tsx
const data = new FormData(event.currentTarget);
const turnstileToken = await challenge("frm_xxxxxxxxxxxxxxxx");
const result = await submit("frm_xxxxxxxxxxxxxxxx", data, { turnstileToken });
```

Import it with `import { challenge, submit } from "@ikiform/sdk";`. Tokens are single use, so call it once per submit.

## From a server action

Create a secret key in the dashboard under **API keys** with the `submissions:write` scope, and store it as an environment variable. Never expose it to the browser: don't prefix it with `NEXT_PUBLIC_`.

`.env.local`:

```bash
IKIFORM_SECRET_KEY=ik_sk_your_secret_key
```

`app/contact/actions.ts`:

```ts
"use server";

export interface ContactState {
  ok: boolean;
  message: string;
  fields?: Record<string, string[]>;
}

export async function sendContact(_previous: ContactState, formData: FormData): Promise<ContactState> {
  const body = new URLSearchParams();
  for (const [name, value] of formData) {
    if (typeof value === "string" && !name.startsWith("$ACTION")) body.append(name, value);
  }
  const response = await fetch("https://ikiform.com/f/frm_xxxxxxxxxxxxxxxx", {
    method: "POST",
    headers: {
      Accept: "application/json",
      Authorization: `Bearer ${process.env.IKIFORM_SECRET_KEY}`,
    },
    body,
  });
  const result = await response.json();
  if (result.ok) return { ok: true, message: "Thanks, we got it." };
  return { ok: false, message: result.error.message, fields: result.error.fields };
}
```

`app/contact/contact-form.tsx`:

```tsx
"use client";

import { useActionState } from "react";
import { type ContactState, sendContact } from "./actions";

const initial: ContactState = { ok: false, message: "" };

export function ContactForm() {
  const [state, action, pending] = useActionState(sendContact, initial);

  if (state.ok) return <p>{state.message}</p>;

  return (
    <form action={action}>
      <label htmlFor="email">Email</label>
      <input id="email" name="email" type="email" required />
      {state.fields?.email ? <p>{state.fields.email[0]}</p> : null}
      <label htmlFor="message">Message</label>
      <textarea id="message" name="message" />
      {state.message && !state.fields ? <p role="alert">{state.message}</p> : null}
      <button disabled={pending}>{pending ? "Sending" : "Send"}</button>
    </form>
  );
}
```

> Posts sent from your server all come from your server's IP address, so Ikiform's per-visitor rate limits count every visitor together. The Standard preset allows 5 posts a minute per IP and form, which a busy site can hit. Post from the browser when you can, or choose the Relaxed or Custom [rate limit](https://ikiform.com/docs/rate-limits.md) for forms you proxy through a server.

The SDK's `submit` can be used in a server action too, but it doesn't send an `Authorization` header, so a form with allowed domains or the Ikiform human check would reject or flag the post. Use `fetch` with the secret key as shown.

## Receive webhooks in a route handler

To act on each submission in your Next.js app, add a route handler. See [Receiving webhooks](https://ikiform.com/docs/guides/webhook-handlers.md#nextjs).