Updated 2016:
With the latest Open Graph 2.5 API tabs endpoint and PHP SDK 5, the code should look like this:
<?php
$fb = new Facebook\Facebook([/* . . . */]);
$response = $fb->post(
'/{page-id}/tabs',
[
'custom_name'=>'My Custom Tab',
'custom_image_url'=>'http://publicly.accessible/image.jpg',
'app_id'=>'{app-id}',
],
'{page-access-token}',
);
Original 2012 post:
I figured it out, it's just like uploading an image. The field is called "custom_image". Presumably they will update the documentation soon. It's nice they enabled this API hook so quickly with the new release!
Here's how to do it with the Facebook PHP SDK:
<?php
$page_access_token = 'XXXXXXX'; // you'll need the manage_pages permission to get this
$facebook = new Facebook(array(
'appId' => 'YOUR_APP_ID',
'secret' => 'YOUR_APP_SECRET',
'fileUpload' => true, // enables CURL @ file uploads
));
$facebook->api(
'/PAGE_ID/tabs/TAB_NAME', // looks like "app_xxxx" where xxxx = APP_ID
'POST' // post to update
array(
'custom_image' => '@' . realpath('path/to/my/file.jpg'),
'custom_name' => 'My App', // give it a custom name if you want too
'access_token' => $page_access_token // access token for the page
)
);
Cheers
