There is a good chance that this has been asked before, but I can't find an answer that works in my situation. I'm a hobby programmer, not a professional developer:-)
I have a client side script running under WordPress (which I don't think is relevant to the problem) that has JavaScript code to perform an ajax call to a server side PHP script (Add_CDB_Record.php). Within Add_CDB_Record.php I have a "require_once" that pulls in another PHP script (include_headers.php) from the same server.
The issue I am battling with is that the code immediately after the "require_once" line in Add_CDB_Record.php is executed BEFORE the include_headers.php script is actually executed.
Worse still, the code in include_headers.php is then executed later (after the remainder of Add_CDB_Record.php has done it's job) and seems to restart the code from the after the require_once (almost like a callback).
A log entry at the start of my include_headers.php is displayed when the require_once is first started, and again a short while afterwards when it is actually executed. I tried putting a sleep(10) after the require_once and that had no effect (other than slowing the script by 10 seconds of course!)
My server currently uses PHP8.0.28. [Corrected the PHP version]
My understanding is that PHP is synchronous by default (meaning that each statement has to finish before the next statement executes, and when the last statement in the script executes the script is returned to the calling script). So my expectation is that the "require_once" would import the include_headers.php file and then execute it before moving on to the remainder of the Add_CDB_Record.php script.
Code examples below are extracts and tidied up to simplify understanding (I hope!).
Thank you for your assistance.
HTML (Client side)
$.ajax({
url: '../wp-content/themes/u-design-child/CDB/Add_CDB_Record.php',
type: 'POST',
datatype: 'json',
timeout: 10000,
data: createDataset()
})
.fail(function (jqXHR, textStatus, errorThrown){
errorintro = 'Ajax Step 1 Add CDB Record failed:';
displayTxt = $.OnXHRError(jqXHR, textStatus, errorThrown)
alert('We are sorry, an error has occurred.');
clear_submit_button();
$.stopSpinner();
return false;
}) // End of request.fail callback handler
.done (function(databack, textStatus, xhr) {
if(databack.includes("Mail Sent")) {
alert ("Thank you. Your details have been received and an email confirmation sent to your email address (if provided).");
resetForm(); //Reload the page
return true;
} else {
alert('ERROR: Your Client record has not been created.\nError: ' + response);
return false;
}
}); // End of request.done callback handler
Extract from Add_CDB_Record.php (server side)
require_once(get_theme_root() . 'include_headers.php');
$AuthResponse = authenticate_access();
//...remaining code here
Extract from include_headers.php (server side)
// provides standard headers, authentication tests, error handling and php utilities
// including....
function authenticate_access() {
$GLOBALS['$clientcaller'] = 'undeclared';
$clientcaller = $GLOBALS['$clientcaller'];
if(isset($_REQUEST['authentic'])) {
$GLOBALS['$clientcaller'] = $_REQUEST['authentic'];
$clientcaller = $GLOBALS['$clientcaller'];
}
// Check current_user to prove logged in as WP or PubLic for genuine public forms
if (isset($_REQUEST['current_user'])) {
if ($_REQUEST['current_user'] !== 'PubLic') {
if(empty($_REQUEST['current_user'])) {
elog('current_user false - immediate exit.');
header('HTTP/1.1 500 Internal Server Error');
header('Content-Type: application/json; charset=UTF-8');
die(safe_json_encode(array('[Error]: ' . $_REQUEST['authentic'] . ' Authenticate_access - Unauthorised Access Procedure Call (U1)')));
exit; //exit if not true
};
} else {
elog('current_user empty:' . $_REQUEST['current_user']);
header('HTTP/1.1 500 Internal Server Error');
header('Content-Type: application/json; charset=UTF-8');
die(safe_json_encode(array('[Error]: Authenticate_access - Unauthorised Access Procedure Call (U4)')));
exit; //exit if authentic not set
}
};
// All genuine calls to this procedure must have authentic=true to continue
if (isset($_REQUEST['authentic'])) {
if(!empty($_REQUEST['authentic'])) {
if ($_REQUEST['authentic'] == 'No') {
elog('Authentic false - immediate exit');
header('HTTP/1.1 500 Internal Server Error');
header('Content-Type: application/json; charset=UTF-8');
die(safe_json_encode(array('[Error]: ' . $_REQUEST['authentic'] . ' Authenticate_access - Unauthorised Access Procedure Call (A3)')));
exit; //exit if not true
};
} else {
elog('Authentic empty:' . $_REQUEST['authentic']);
header('HTTP/1.1 500 Internal Server Error');
header('Content-Type: application/json; charset=UTF-8');
die(safe_json_encode(array('[Error]: Authenticate_access - Unauthorised Access Procedure Call (A4)')));
exit; //exit if authentic not set
}
return true;
};
//Fall through all checks - catch in case
elog('Authentic missing (all checks)');
header('HTTP/1.1 500 Internal Server Error');
header('Content-Type: application/json; charset=UTF-8');
die(safe_json_encode(array('[Error]: Authenticate_access - Unauthorised Access Procedure Call (A5)')));
exit;
//exit if authentic doesn't exist
$erroroccurred = false;
//error handler function
function customError($errno,$errstr,$errfile,$errline,$errcontext) {
echo "<b>Error:</b> ($errline) [$errno] $errstr in $errfile<br />$errcontext<br />";
elog ("Error: " . "(" . $errline . ")" . "[" . $errno . "]" . $errstr . " in " . $errfile . "|" . $errcontext );
global $erroroccurred;
$erroroccurred = true;
}
//set error handler
set_error_handler("customError",E_ALL);
return;
}//end authenticate_access function
