Is it possible to have a Facebook app in multiple languages? - php

Question

I'm trying to make it so my facebook app is available in English and Japanese.
I tried using tags but could not get them to work:
http://developers.facebook.com/docs/internationalization/
I then thought I'd just make two versions of the app, one in English, the other in Japanese. When I open my app, the oauth permission dialog is shown. I approve the app and then it takes me to a page which keeps looping, producing a new $_GET['code'] each time. I then click on "facebook" at the top left hand corner of the screen. I then click on my app again and this time I can access it ok in English or Japanese. How can I stop the app looping the first time around? How can I go directly to the version of the app based on the users locale? Thanks
<?php
function parse_signed_request($signed_request, $secret) {
list($encoded_sig, $payload) = explode('.', $signed_request, 2);
// decode the data
$sig = base64_url_decode($encoded_sig);
$data = json_decode(base64_url_decode($payload), true);
if (strtoupper($data['algorithm']) !== 'HMAC-SHA256') {
error_log('Unknown algorithm. Expected HMAC-SHA256');
return null;
}
// check sig
$expected_sig = hash_hmac('sha256', $payload, $secret, $raw = true);
if ($sig !== $expected_sig) {
error_log('Bad Signed JSON signature!');
return null;
}
return $data;
}
function base64_url_decode($input) {
return base64_decode(strtr($input, '-_', '+/'));
}
$result = parse_signed_request($_REQUEST['signed_request'],"app_secret");
$locale = $result['user']['locale'];
$token = $result['oauth_token'];
if ($token != ""){
if ($locale == "ja_JP"){
if ($_SERVER['HTTPS']){
header("Location: https://secure.example.com/facebook/ja/index.php");
exit;
}
else {
header("Location: http://example.com/facebook/ja/index.php");
exit;
}
}
else{
if ($_SERVER['HTTPS']){
header("Location: https://secure.example.com/facebook/en/index.php");
exit;
}
else {
header("Location: http://example.com/facebook/en/index.php");
exit;
}
}
}
else {
if($_SERVER['HTTPS']){
$canvas_page = "https://secure.example.com/facebook/";
}
else {
$canvas_page = "http://example.com/facebook/";
}
$app_id = "my_app_id";
$auth_url = "http://www.facebook.com/dialog/oauth?client_id="
. $app_id . "&redirect_uri=" . urlencode($canvas_page) . "&scope=email";
$signed_request = $_REQUEST["signed_request"];
list($encoded_sig, $payload) = explode('.', $signed_request, 2);
$data = json_decode(base64_decode(strtr($payload, '-_', '+/')), true);
echo("<script> top.location.href='" . $auth_url . "'</script>");
exit;
}
?>

Answer 1

You could put all your texts in a simple locale-based array. You first need to get the user's locale, then use it as a key
$loc["ja_JP"]["MyText"] = "My JP text";
$loc["en_US"]["MyText"] = "My US text";
$result = parse_signed_request($_REQUEST['signed_request'],"app_secret");
$locale = $result['user']['locale'];
echo $loc[$locale]["MyText"];
For resources (specific localized pictures for example), you could get the files in a locale-based directory.