wp_remote_post with file payload - wordpress

Question

I'm attempting to POST a file through wp_remote_post. Unfortunately, any file stream, or file paths (prepended with CURL style #, or not), passed to this function are simply dropped and removed from the payload.
I found a post on wp-hackers, however, it's extremely hack-ish and error prone. Is there really no way to transmit a file through this function without writing a complete HTTP payload from scratch?
Here's an example code block using CURL style (prepending path with #), if interested:
$body["attachment[{$i}]"] = "#{$attachment}";
$data = array(
'body' => $body,
'headers' => array(
'Authorization' => 'Basic ' . base64_encode( "user:{$apiKey}" )));
$url = "https://api.someservice.net/{$domain}/endpoint";
$response = wp_remote_post( $url, $data );
Thanks!

Answer 1

Post data should be sent in the body as an array. Example passing post data:
$response = wp_remote_post( $url, array(
'method' => 'POST',
'timeout' => 45,
'redirection' => 5,
'httpversion' => '1.0',
'blocking' => true,
'headers' => array(),
'body' => array( 'username' => 'bob', 'password' => '1234xyz' ),
'cookies' => array()
)
);
if ( is_wp_error( $response ) ) {
$error_message = $response->get_error_message();
echo "Something went wrong: $error_message";
} else {
echo 'Response:<pre>';
print_r( $response );
echo '</pre>';
}
In the example above, $response['body'] will contain the actual page content returned by the server.