HTTP 504 timeouts by running this PHP script - php

Question

I have a PHP script below that I'm running every hour using a cronjob. Sometimes this script runs without any errors and other times it throws a 504 Gateway Timeout.
Can someone please help to improve the execution and efficiency of this script? I believe it can be written cleaner, but not sure where to start.
This is on a shared server and I do not have much control over the settings. Max timeout is 120.
Cronjob:
curl www.mysite.com/apps/script.php
PHP script:
<?php
set_time_limit(500);
$databasehost = "localhost";
$databasename = "foodb";
$databasetable = "footable";
$databaseusername="foouser";
$databasepassword = "foopass";
$fieldseparator = ",";
$lineseparator = "\n";
$csvfile = "inventory.csv";
if(!file_exists($csvfile)) {
die("File not found. Make sure you specified the correct path.");
}
try {
$pdo = new PDO("mysql:host=$databasehost;dbname=$databasename",
$databaseusername, $databasepassword,
array(
PDO::MYSQL_ATTR_LOCAL_INFILE => true,
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION
)
);
$sql = "TRUNCATE TABLE $databasetable";
$command = $pdo->prepare($sql);
$command->execute();
echo "Removed records from $databasename.\n<br />";
} catch (PDOException $e) {
die("database connection failed: ".$e->getMessage());
}
$affectedRows = $pdo->exec("
LOAD DATA LOCAL INFILE ".$pdo->quote($csvfile)." INTO TABLE `$databasetable`
FIELDS TERMINATED BY ".$pdo->quote($fieldseparator)."
LINES TERMINATED BY ".$pdo->quote($lineseparator)."IGNORE 1 LINES");
echo "Loaded a total of $affectedRows records from this csv file.\n";
/****/
try {
$pdo = new PDO("mysql:host=$databasehost;dbname=$databasename",
$databaseusername, $databasepassword,
array(
PDO::MYSQL_ATTR_LOCAL_INFILE => true,
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION
)
);
$sql = $pdo->exec("
UPDATE wp37_pmxi_posts
JOIN wp37_postmeta USING (post_id)
JOIN inventoryImport ON wp37_pmxi_posts.unique_key = inventoryImport.sku
SET meta_value = inventoryImport.qty
WHERE meta_key = '_stock'");
echo "Updated $affectedRows records after the import.\n";
} catch (PDOException $e) {
die("database connection failed: ".$e->getMessage());
}
?>
Thanks for your time and I appreciate any help.

Answer 1

I had the exact same issue last week and even though I am on a VPS server with a full root access, I didn't want to mess about with the files in the etc/ folder or php.ini or any other PHP settings...
So I came up with my own solution..
Please note this solution and this answer intended to just give you and other people an idea of how you could solve this issue without fiddling with server settings...
The solution was quite simple actually...
First i created an extra column in the MYSQL database with a pre-defined value of 0. You can name it anything you want.
What I did next was basically LIMIT my SELECT to 100.
something like:
SELECT * FROM mytable WHERE newColumn=0 LIMIT 100
And then I did whatever i wanted with this 100 selected items and every time I did that i UPDATE the database and changed the newColumn=1
And I repeated the same process until there is no more data in the MYSQL database with newColumn=0.
once I reach this stage, I UPDATE the table again and reset the newColumn back to 0.
Note that I run the process above on cron job.
This way your PHP won't get killed as you are only selecting 100 rows from the MYSQL.
hope this helps.