oauth.php

<?php

$args = array(
    'code' => $_REQUEST['code'],
    'app_id' => self::setting( 'clef_settings_app_id' ),
    'app_secret' => self::setting( 'clef_settings_app_secret' ),
);

$response = wp_remote_post( 
    CLEF_API_BASE . 'authorize', 
    array( 'method'=> 'POST', 'body' => $args, 'timeout' => 20 ) 
); 

if ( is_wp_error($response)  ) {
    $_SESSION['Clef_Messages'][] = "Something went wrong, please try again";
    self::redirect_error();
    return;
}

?>