How to edit moodle sql to time access - mysql

Question

I'm trying to change my Moodle in 2.6 version.
I want to do something like this: When user is logged in ,He have permission to watch all materials but only when his account is active.
I want to edit sql database to add 1 field 'is_active' and set there datetime stamp.
For Example I have user John Doe , i put in database in field 'is_active' date 25.02.2014 and he can watch all lessons ans stuff till 25.02.2014 after that his account goes unactivate and when he tries to log in he will have information that his account is not active and he has to contact with administrator.
Can you tell me witch Database query change to check that permission when user is trying to log in ? I think that resolution will be to get current date from server and check it with date in database. If system date is lower that database user have access , if date is higher user doesn't have access and he gets info.
If somebody doesn't understand sorry for my english write in comments i will try to describe more.

Answer 1

I would create a user profile field 'is_active', choose datetime and set it to 'Not visible'
site admin -> users -> accounts -> user profile fields
http://docs.moodle.org/26/en/User_profile_fields
Then create a local plugin that uses cron to check the date and sets the user to suspended
In /local/is_active/version.php - http://docs.moodle.org/dev/version.php
defined('MOODLE_INTERNAL') || die();
$plugin->version = 201402301; // Plugin version
$plugin->requires = 2013051402; // Moodle version.
$plugin->component = 'local_is_active'; // Component name
$plugin->cron = 1; // In seconds - how often should this be run?
In /local/is_active/lang/en/local_is_active.php
$string['pluginname'] = 'Is active';
In /local/is_active/lib.php have a cron function local_xxx_cron() that updates the user table to suspended. I haven't tested the SQL but something like this
defined('MOODLE_INTERNAL') || die();
function local_is_active_cron() {
$sql = "UPDATE {user}
SET suspended = :suspended
WHERE EXISTS (SELECT userid
FROM {user_info_field} f
JOIN {user_info_data} d ON d.fieldid = f.id
AND d.data < :now
AND d.userid = mdl_user
WHERE f.shortname = :shortname)";
$params = array('suspended' => 1,
'now' => time(),
'shortname' => 'is_active');
$DB->execute($sql, $params);
}
EDIT : Forgot to add that you will need to go to notifications to install the plugin - site admin -> notifications - then Moodle will automatically call the cron function when cron is run.
You can run cron manually by going to /admin/cron.php
As a site admin you can edit the date via the users profile - go to site admin -> users -> accounts -> browse list of users -> then click the pencil next to a user profile
Or update the date using something like this - the data field needs to be a unix timestamp rather than a string type date
$activedate = strtotime('2014-02-23'); // Timestamp
$fieldid = $DB->get_field('user_info_field', 'id', array('shortname' => 'is_active'));
$params = array('fieldid' => $fieldid, 'userid' => $userid);
if ($DB->record_exists('user_info_data', $params)) {
$DB->set_field('user_info_data', 'data', $activedate, $params);
} else {
$data = new stdClass();
$data->fieldid = $fieldid;
$data->userid = $userid;
$data->data = $activedate;
$data->dataformat = 0;
$DB->insert_record('user_info_data', $data);
}