PHP - running script within a loop - php

Question

I am trying to run a script from within a script and have the below which does not seem to work. I am basically getting a load of data from a database, looping through each row and running a script that will generate XML based on that data.
set_time_limit(0);
//connect to database
$msSqlDB = new mySqlConnect('store');
$select = "SELECT * FROM FStores";
$run = mysql_query($select);
while($row = mysql_fetch_array($run)){
exec('/var/www/web/shop_xml/index.php?shopKeeper=$row[SKID]&shop=1');
}
Whats the best possible way to do this? Will the 2nd row wait until the 1st row is successfully executed or can multiple run at the same time? Many thanks for any advice with this.

Answer 1

You need to do something like this:
exec('php /var/www/web/shop_xml/index.php "'.escapeshellarg($row['SKID']).'" "1" > /dev/null 2>&1 &');
Then, in your index.php script:
<?php
$shopKeeper = $argv[1];
$shop = $argv[2];
// ... do stuff
What you have attempted to do is use a HTTP query string in a file system invoke, which will not work. You need to pass the data as command-line arguments, like you would in a terminal. Then, you can get the data from $argv.
You need to start the command with php otherwise the kernel will (most likely, unless you add a hashbang and set permissions) not know how to execute the script, or have permissions to do it.
If you add > /dev/null 2>&1 & the commands will be run asynchronously, i.e. you will not have to wait for the last command to finish before you can invoke another. Be carefull with this though, you could end up with many processes if your query returns many rows.
To avoid this, you could do somthing like:
<?php
// Number of records to process at a time
$perBatch = 5;
set_time_limit(0);
//connect to database
$msSqlDB = new mySqlConnect('Freewebstore');
// Get the number of records in the table
$query = "SELECT count(*) FROM FacebookStores";
$result = mysql_fetch_row(mysql_query($select));
$count = $result[0];
for ($i = 0; $i < $count; $i += $perBatch) {
// Get $perBatch records from the DB
$query = "SELECT * FROM FacebookStores LIMIT $i,$perBatch";
$result = mysql_query($select);
for ($j = 1; $row = mysql_fetch_array($result); $j++) {
// Base command
$command = 'php /var/www/web/shop_xml/index.php "'.escapeshellarg($row['SKID']).'" "1"';
// Run all except the last asynchronously
if ($j < $perBatch) {
$command .= ' > /dev/null 2>&1 &';
}
exec($command);
}
}
This would get $perBatch records from the DB at a time, and process all but the last asynchronously. This would result in them being processed roughly $perBatch records at a time, and help to avoid a large number of processes eating server resources.
As a side note, you seem to be using an odd mix of OO DB code and procedural DB code - you should stick to one or the other to avoid confusion.

Answer 2

The answer by George P answers your question literally; how to run the script as-is from the command line. Let me in turn offer some alternatives.
First of all, your shop_xml/index.php script could check to see if it is being called from command line and read arguments accordingly. Thus:
if( php_sapi_name() == 'cli' ) {
// you would, of course, want to escape these for malicious code!
$shopKeeper = $argv[1];
$shop = $argv[2];
}
else {
$shopKeeper = $_GET['shopKeeper'];
$shop = $_GET['shop'];
}
Then you would call your command as follows:
$arg = escapeshellarg($row['SKID']);
exec( "/var/www/web/shop_xml/index.php \"$arg\" 1" );
However, a far better solution would be to take the code in index.php which is being called from the CLI and move it to an include (like functions.php), placing it inside a function like so:
function processShopRow($showKeeper, $shop) {
// stuff that used to be in index.php goes here
}
Now, in both index.php and in the code run from the CLI, you will include and run the code as follows:
include('functions.php');
set_time_limit(0);
//connect to database
$msSqlDB = new mySqlConnect('Freewebstore');
$select = "SELECT * FROM FacebookStores";
$run = mysql_query($select);
while($row = mysql_fetch_array($run)){
processShopRow($row['SKID'], 1);
}

Answer 3

your script is not working becuase
exec('/var/www/web/shop_xml/index.php?shopKeeper=$row[SKID]&shop=1');
make it
exec("/var/www/web/shop_xml/index.php?shopKeeper=$row[SKID]&shop=1");
single quotes can't have variables inside them.

Answer 4

Have you tried using this:
exec("/var/www/web/shop_xml/index.php?shopKeeper=$row[SKID]&shop=1");
instead of your original? The single quotes ' don't allow you to evaluate embedded variables or php objects in it. You'll have to use the double quotes " --Could you try that out?

Answer 5

In your exec command you need to either run the script using lynx (command line browser) or the PHP CLI. You also should reference the domain, not the full path:
exec("php http://domain.com/index.php?shopKeeper=$row[SKID]&shop=1");

Answer 6

exec() attempts to invoke a program on your server's file system, exactly as if you'd typed in the exec() parameter at a shell prompt. Shells do not know what to do with a URL, so you'll get a "no matching files" error, as the ? in the url will be seen as a shell wildcard.
If you want to request a url, you'd have to at minimum do
$output = file_get_contents("/var/www/etc....");
and PHP will do a full HTTP request for you.