Chamilo LMS

In order to develop the mobile app to get your personal Chamilo messages on your smartphone, we need a series of webservices as described below. The objective of this task is to develop these web services.

File¶

In order to develop REST webservices (which don't really exist in any coordinated fashion in Chamilo), we will create a main/webservices/rest.php file which contains the main controller and the available webservices, and will call Chamilo functions/methods as needed

Authentication¶

We want to ensure an authentication that is as secure as possible, but this will require HTTPS (we cannot ensure security in the communication with a non-HTTPS Chamilo portal).

The first connection with any Chamilo portal, in the mobile app, will require the URL of the portal and the introduction of the login/password information.
This will generate a new API key (a new user field of type "text" called api_key_message, or the existing one if one already exists). The API key is a random SHA1 key.

The SHA1 key is returned by the webservice, so the mobile application can store it.

So, something like this (all the function names are invented):

if (isValidPassword($username, $password)) {
    $userInfo = api_get_user_info($username);
    if (UserField::fieldExists('api_key_message')) {
        $apiKey = UserField::get_field_value('api_key_message', $username);
        return json_encode('result' => $apiKey);
    } else {
        UserField::createUserField('api_key_message');
        $apiKey = generateApiKey();
        $result = UserField::create('api_key_message', $username, $apiKey);
        if ($result) {
            return json_encode('result' => $apiKey);
        } else {
            return json_encode('result' => false);
        }
    }
} else {
    return json_encode('result' => false);
}

Later on, all other webservices will only work with the API key.

Web services¶

Get new messages count¶

public function getNewMessagesCount($username, $apiKey, $last = 0) {
    $userInfo = api_get_user_info_from_username($username);
    // get count of new messages for this user, since the last message already received
    return json_encode('result' => $count);
}

Get new messages¶

public function getNewMessages($username, $apiKey, $last = 0) {
    $userInfo = api_get_user_info_from_username($username);
    // get new messages for this user, since the last message already received
    $messages = ...
    // $messages should be an array something like this:
    // 0 => array('id' => $row['id'], 'title' => $row['title'], 'sender' => $row['sender'], 'content' => $row['content']),
    // 1 => array('id' => ...),
    // 2 => array('id' => ...), ...
    return json_encode(
        'result' => $count,
        'messages' => $messages
    );
}