> ## Documentation Index
> Fetch the complete documentation index at: https://docs.modelence.com/llms.txt
> Use this file to discover all available pages before exploring further.

# loginWithOAuth

[API Reference](/api-reference/modelence/client/functions/../../../index) / [modelence](/api-reference/modelence/client/functions/../../index) / [client](/api-reference/modelence/client/functions/../index) / loginWithOAuth

> **loginWithOAuth**(`options`): `Promise`\<`null` | `User`>

Defined in: [packages/modelence/src/auth/client/index.ts:500](https://github.com/modelence/modelence/blob/b3abdbf506f9ad1e225780ceb0087367c98e6d24/packages/modelence/src/auth/client/index.ts#L500)

Complete a native OAuth sign-in with the code from the deep link.

Exchanges the single-use code that [signInWithOAuth](/api-reference/modelence/client/functions/signInWithOAuth) delivered to your
app's deep link for a session, stores the auth token, and returns the
signed-in user. Codes are valid for one minute and can only be redeemed once.

Pairs with `signInWithOAuth({ provider, redirectUri })` — the flow that hands
a code back to your app. It works on native and under Expo Web, where the
verifier is kept in `sessionStorage` so it survives the navigation to the
provider.

When this page is an OAuth popup opened by a page that is still listening —
the embedded-iframe case, where `openUrl` returned the window from
`window.open` — the code is handed to that opening page instead, and the
sign-in completes *there*, in the context the app actually runs in. This call
then resolves to `null`: there is no user to return here, and this page is
closed for you. A plain web app that calls `signInWithOAuth({ provider })`
with no `redirectUri` is signed in by a session cookie and never needs this.

The verifier minted by `signInWithOAuth` is replayed by whichever context
redeems the code, which is what makes a code usable only by the client that
started the flow. Calling this without a preceding `signInWithOAuth` — as a
crafted deep link would — fails before the code is ever sent.

## Example

```ts theme={null}
const user = await loginWithOAuth({ code });
if (user) {
  // Signed in here. In an embedded popup, user is null and the opening
  // page has completed the sign-in instead.
}
```

## Parameters

| Parameter      | Type                   | Description                                    |
| -------------- | ---------------------- | ---------------------------------------------- |
| `options`      | \{ `code`: `string`; } | -                                              |
| `options.code` | `string`               | The `code` query parameter from the deep link. |

## Returns

`Promise`\<`null` | `User`>