connect to FTP using array values - php

Question

I am new to php and struggling to get the data from a table in mysql and using it to connect to an ftp server. The table contains the external ip address of the ftp server, the base directory to change into and login credentials to use. I fetched the data from mysql and stored it in an array but while looping through it I get
php notice: trying to access array offset on type null.
Code:
$now = time();
$yesterday = $now - (24 * 60 * 60);
$date = date("Y-m-d", $yesterday);
if (isset($_GET['date'])) {
$date = $_GET['date'];
}
$startDate = "$date 00:00:00";
$endDate = "$date 23:59:59";
//$conn = &newEtConn();
$sql= "SELECT stager_usr, stager_pwd, stager_ip, basedir, view_direction from et_devices.cameras as a inner join et_params.stagers as b on a.stagerid = b.idstagers ";
$result = mysqli_query($conn,$sql);
$datas = array();
if (!$result) {
die ("table Connection problem");
}
if (mysqli_num_rows($result)>0){
while ($row = mysqli_fetch_assoc($result)){
$datas[] = $row;
}
print_r($datas);
}
if ($row!= "") {
foreach ($datas as $values) {
$ip_addr = $values['stager_ip'];
$login = $values['stager_usr'];
$password = $values['stager_pwd'];
$basedir = $values['basedir'];
if ($rows != "") {
$gotFtpConn = True;
$ftp_obj = ftp_connect($ip_addr, 21, 10) or $gotFtpConn = False;
if ($gotFtpConn) {
if (ftp_login($ftp_obj, $login, $passwd)) {
echo "could not connect" . $login;
return false;
}
return $newEtConn;
}
}
}

Answer 1

There are a few things that I don't like (and can improve)...
It looks like you intend to filter your database data based on a date, but then you never actually apply that value to the array. I'll help to clean up that process.
Your if ($row != '') check after the loop will always fail because the loop ONLY stops when $row becomes falsey.
The rest of your code looks like it only intends to process a single row in the result set (because it returns). I am going to assume that you have more conditional logic in your query's WHERE clause which ensures that only one row is returned -- otherwise, you shouldn't be using return in your loop.
$date = !empty($_GET['date']) && preg_match('/^\d{4}-\d{2}-\d{2}$/', $_GET['date'])
? $_GET['date']
: date('Y-m-d', strtotime('yesterday'));
$sql = "SELECT stager_usr, stager_pwd, stager_ip
FROM et_devices.cameras AS a
JOIN et_params.stagers AS b ON a.stagerid = b.idstagers
WHERE DATE(a.some_datetime_column) = ?";
$stmt = $conn->prepare($sql);
$stmt->bind_param('s', $date);
$stmt->execute();
foreach ($stmt->get_result() as $row) {
$ftp = ftp_connect($row['stager_ip'], 21, 10);
if (!$ftp) {
throw new Exception('Failed to establish FTP connection');
}
if (!ftp_login($ftp, $row['stager_usr'], $row['stager_pwd'])) {
throw new Exception('Incorrect FTP login credentials');
}
return $ftp;
}
throw new Exception('FTP connection data not found');
If you experience a noticeable performance bottleneck with DATE() in your sql, then there are other techniques that may be faster, but they use longer/uglier syntax.