Progressbar using php and jquery - php

Question

I want to make a mail send program and notify the user with a progress bar while waiting. Unfortunately it does not work as expected, the progressbar is not updated.
The Program loops through an array of mail adresses derived from a database. There first the mail address will be verified fro existence in the mailbox. If not, it will be reported. The reports are collected and at the end sent back to the browser.
The progress is reported by separate ajax posts every second by the javascript function "mitgl.progressBar" and sent by the server via the function "getProgress" at the bottom of the php.
Mail verification and mail sending works but the getProgress seems only be made once instead.
Altough the attached code is only a fragment, the rest of the code works fine.
I cannot find the problem, perhaps someone can see what i am blind for...
Javascript:
versandMail: function() {
mitgl.unselectRec();
mitgl.pInt = window.setInterval(mitgl.progressBar, 1000);
var oForm = $('form[name=vs]').get(0);
$.post(location.href, {
cmd: 'M mailVersand',
de: oForm.de.value,
fr: oForm.fr.value,
sr: oForm.sr.value,
aktiv: oForm.aktiv.value,
anfragen: oForm.anfragen.value,
vorstand: oForm.vorstand.value,
idList: (oForm.idList ? oForm.idList.value : ''),
betreff: oForm.betreff.value,
mailtext: $('textarea[name=mailtext]', oForm).htmlarea('html'),
attachments: JSON.stringify(mitgl.oVersand.mail.attachments)
}, function(data, status, oXhr){
window.clearInterval(mitgl.pInt);
$('#progressbar').remove();
$('#mailReport').remove();
if (data.isEmpty()) {
window.alert('Auswahl hat keine Adressen ergeben');
} else if (data.substr(0, 6) === 'Fehler') {
window.alert(data);
} else {
$('#protokoll tbody').html(data);
mitgl.protoLink();
mitgl.selectTop();
}
});
},
progressBar: function() {
$.post(location.href, {
cmd: 'M getProgress'
}, function(nProgress) {
if ($('#progressbar').length > 0) {
$('#progressbar .bar').css({width: nProgress+'%'});
} else {
var pb = $('<div/>')
.attr('id', 'progressbar')
.appendTo('#cmd');
$('<div/>')
.addClass('bar')
.appendTo(pb);
}
});
},
PHP:
function mailVersand() {
// ... Prepare Mail Data ...
require_once 'phpmailer.class.php';
require_once('class.smtp.php');
require_once('class.verifyEmail.php');
$oVerify = new verifyEmail();
$oVerify->setEmailFrom($cMailFrom);
$oMail = new PHPMailer();
$oMail->SMTPDebug = 0;
$oMail->IsSMTP(); // telling the class to use SMTP
//
// ... and so on ...
$oMail->Host = ...
$aErrors = [];
$nSent = 0;
$nError = 0;
$nProcessed = 0;
$nMails = count($aMitglied);
session_start(); // <-- Session starts
$_SESSION['nProgress'] = '0'; // progress is zero
// loop through mailing list
foreach ($aMitglied as $r) {
$aEmail = explode(';', $r->email);
$email = $aEmail[0];
if ($oVerify->check($email)) {
$oMail->AddAddress($email,"$r->vorname $r->name");
// mail verificatio is ok, try to send
if ($oMail->send() === TRUE) {
$nSent++;
} else {
// no, report error
$e = new stdClass();
$e->email = $email;
$e->name = $r->name;
$e->vorname = $r->vorname;
$e->error = $oMail->ErrorInfo;
$aErrors[] = $e;
$nError++;
}*/
$oMail->ClearAddresses();
} else {
// Mail verification failed, report error
$e = new stdClass();
$e->email = $r->email;
$e->name = $r->name;
$e->vorname = $r->vorname;
$e->error = $oVerify->getAllErrors();
$aErrors[] = $e;
$nError++;
}
$nProcessed++; // <-- Next processed record
// v-- Calulate percentage of progress
$_SESSION['nProgress'] = strval(round($nProcessed *100 /$nMails));
}
// create error report
$oBericht = new stdClass();
$oBericht->sent = $nSent;
$oBericht->error = $nError;
$oBericht->fails = $aErrors;
// now procedure finished, reply final report
// ....
$s = $this->listVersand();
echo ($s); // send reply
session_write_close(); // session ends
exit;
}
function getProgress() {
session_start();
//$n = isset($_SESSION['nProgress']) ? "$_SESSION[nProgress]" : "5";
$n="20";
echo ($n);
exit();
}

Answer 1

I found the problem. Sessions can store values between successive calls to a webpage. What I was intended to do is passing a value between active PHP processes.
One way to do this is using APC calls. However this is not available anymore in php versions newer than 5.3, so I have chosen a way to store the progress information in a database.
It's not very effective, it uses a lot of recources. If someone knows a better way to share variables between active php processes it would be nice to tell it here.