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run php function using ajax to update phpBB template variable

NOTE: There are a lot of details here, so if anyone needs a condensed version of this, I'm happy to summarize.
I am trying to run a function in my php file, that will in turn, update a template variable. As an example, here is one such function:
function get_vehicle_makes()
{
$sql = 'SELECT DISTINCT make FROM phpbb_vehicles
WHERE year = ' . $select_vehicle_year;
$result = $db->sql_query($sql);
while($row = $db->sql_fetchrow($result))
{
$template->assign_block_vars('vehicle_makes', array(
'MAKE' => $row['make'],
));
}
$db->sql_freeresult($result);
}
I know that this function works. I am trying to access this function in my Javascript with:
function updateMakes(pageLoaded) {
var yearSelect = document.getElementById("vehicle_year");
var makeSelect = document.getElementById("vehicle_make");
var modelSelect = document.getElementById("vehicle_model");
$('#vehicle_make').html('');
$.ajax({ url: '/posting.php',
data: {action: 'get_vehicle_makes'},
type: 'post',
success:function(result)//we got the response
{
alert(result);
},
error:function(exception){alert('Exception:'+exception);}
});
<!-- BEGIN vehicle_makes -->
var option = document.createElement("option");
option.text = ('{vehicle_makes.MAKE}');
makeSelect.add(option);
<!-- END vehicle_makes -->
if(pageLoaded){
makeSelect.value='{VEHICLE_MAKE}{DRAFT_VEHICLE_MAKE}';
updateModels(true);
}else{
makeSelect.selectedIndex = -1;
updateModels(false);
}
}
The section in my javascript...
<!-- BEGIN vehicle_makes -->
var option = document.createElement("option");
option.text = ('{vehicle_makes.MAKE}');
makeSelect.add(option);
<!-- END vehicle_makes -->
... is a block loop and will loop through the block variable, vehicle_makes, set in the PHP function. This works upon loading the page because the page that loads, is the new.php that I'm trying to do an Ajax call to, and all of the PHP runs in that file upon loading. However, I need the function to run again, to update that block variable, since it will change based on a selection change in the HTML. I don't know if this type of block loop is common. I'm learning about them since they are used with a forum I've installed on my site, phpBB. (I've looked in their support forums for help on this.). I think another possible solution would be to return an array, but I would like to stick to the block variable if possible for the sake of consistency.
This is the bit of code in the php that reads the $_POST, and call the php function:
if(isset($_POST['action']) && !empty($_POST['action'])) {
$action = $_POST['action'];
//Get vehicle vars - $select_vehicle_model is used right now, but what the heck.
$select_vehicle_year = utf8_normalize_nfc(request_var('vehicle_year', '', true));
$select_vehicle_make = utf8_normalize_nfc(request_var('vehicle_make', '', true));
$select_vehicle_model = utf8_normalize_nfc(request_var('vehicle_model', '', true));
switch($action) {
case 'get_vehicle_makes' :
get_vehicle_makes();
break;
case 'get_vehicle_models' :
get_vehicle_models();
break;
// ...etc...
}
}
And this is the javascript to run the Ajax:
function updateMakes(pageLoaded) {
var yearSelect = document.getElementById("vehicle_year");
var makeSelect = document.getElementById("vehicle_make");
var modelSelect = document.getElementById("vehicle_model");
$('#vehicle_make').html('');
$.ajax({ url: '/posting.php',
data: {action: 'get_vehicle_makes'},
type: 'post',
success:function(result)//we got the response
{
alert(result);
},
error:function(exception){alert('Exception:'+exception);}
});
<!-- BEGIN vehicle_makes -->
var option = document.createElement("option");
option.text = ('{vehicle_makes.MAKE}');
makeSelect.add(option);
<!-- END vehicle_makes -->
if(pageLoaded){
makeSelect.value='{VEHICLE_MAKE}{DRAFT_VEHICLE_MAKE}';
updateModels(true);
}else{
makeSelect.selectedIndex = -1;
updateModels(false);
}
}
The javascript will run, and the ajax will be successful. I've checked the network tab and console tab, and have done multiple tests to confirm that. It appears that the block variable is not being set. Is what I'm trying to do even possible? I have a feeling that to get this answer, we'll need to know more about phpBB's template engine, and how it works with these template variable. Also, just to clarify, I think the term 'template variable' is specific to phpBB. It's the term they use for variables set in PHP, to be accessed by the HTML, and javascript files. This works through a phpBB class called 'template', and a function called 'assign_block_vars'. I don't know exactly how that work.
If anyone has done this for phpBB, or has any ideas, I would appreciate it.

Think I found the problem. At the beginning of my PHP, I have an include statement to include the PHP file containing the class for connecting to the database. In the statement $result = $db->sql_query($sql);, $db is set in this other PHP file. I don't entirely understand, but because of that, $db was outside of the scope of my function get_vehicle_makes(). I had to create a class inside my PHP file, and pass $db as a parameter to the function using:
class vehicle {
public function __construct($db)
{
$this->db = $db;
}
function get_vehicle_makes()
{
$sql = 'SELECT make FROM phpbb_vehicles
WHERE year = ' . $select_vehicle_year;
$result = $this->db->sql_query($sql);
Hope this helps.

Refresh PHP Page when data in Database Updated

I want my client side web to auto-refresh when data in my Database updated, when adding or deleting data I have succeeded however when the data changed, it still fails.
This is my code for checking data from database:
<script>
var row1 = "<?php echo $variable; ?>";
var processUpdate = function( response ) {
var x = response;
//console.log(x);
if (row1 != x) {
window.location.reload();
}
}
var checkUpdates = function() {
serverPoll = setInterval(function() {
$.get('check.php', { lastupdate: 1 }, processUpdate, 'html');
}, 1000)
};
$(document).ready(checkUpdates);
</script>
check.php:
$query = mysqli_query($koneksi, "SELECT * FROM table");
$number = mysqli_num_rows($query);
echo $number;
What should I change to be automatically refreshed if every data in the table is changed?

You can use trigger that will insert some info about each table update in another table, and then just query the num rows on 'changes' table in a similar way you check for new ones here:
DELIMITER //
CREATE TRIGGER table_update_trigger AFTER UPDATE ON table
FOR EACH ROW BEGIN
INSERT INTO table_history
(
change
)
(
NEW.some_value,
);
END
//
The advantage of this solution is you don't need to introduce/rely on/maintain any other db system like Redis and the checking code is not responsible for keeping and updating any counters and queries for updates, inserts and deletes in a similar fashion. Also you might extend the table_history table to log all the fields you are interested in in terms of tracking changes and end up having useful changelog for the purpose of the application.

jQuery open page in a new tab while passing POST data

I have a javascript variable called "list". I need to send it as a POST data to another page and open that page in a new tab (with the POST data present).
This code:
jQuery.post('datadestination.php', list);
sends the data all right, but ofcourse it opens the page in the same tab.
I saw some solutions to similar problems using invisible form and things like that, but I could not get them to work. Is there any simple solution?

You can send a form using the target="_blank" attribute.
<form action="datadestination.php" method="POST" target="_blank" id="myform">
<input type="hidden" name="list" id="list-data"/>
<input type="submit" value="Submit">
</form>
Then in JS:
jQuery('#list-data').val(list);
jQuery('#myform').submit();

This is an implementation of Sergey's solution.
<?php // this is save.php
session_start();
// DO NOT just copy from _POST to _SESSION,
// as it could allow a malicious user to override security.
// Use a disposable variable key, such as "data" here.
// So even if someone passed _POST[isAdmin]=true, all that he would do
// is populate _SESSION[data][isAuthenticated], which nobody reads,
// not the all-important _SESSION[isAuthenticated] key.
if (array_key_exists('data', $_POST)) {
$_SESSION['data'] = $_POST['data'];
$_SESSION['data.timestamp'] = time();
// Let us let the client know what happened
$msg = 'OK';
} else {
$msg = 'No data was supplied';
}
Header('Content-Type: application/json; charset=utf8');
die(json_encode(array('status' => $msg)));
?>
In the first page:
$.post('save.php', { data: list }, function(response){
if (!response.status) {
alert("Error calling save");
return;
}
if (response.status !== 'OK') {
alert(response.status);
return;
}
// We had a response and it was "OK". We're good.
window.open('datadestination.php');
});
And in datadestination.php add the fix:
if (!array_key_exists('data', $_SESSION)) {
die("Problems? Did you perchance attempt to reload the page and resubmit?");
// For if he did, then yes, $_SESSION would have been cleared.
// Same if he is operating on more than one window or browser tab.
}
// Do something to validate data. For example we can use data.timestamp
// to assure data isn't stale.
$age = time();
if (array_key_exists($ts = 'data.timestamp', $_SESSION)) {
$age -= $_SESSION[$ts];
}
if ($age > 3600) {
die("Data is more than one hour old. Did someone change server time?!?");
// I actually had ${PFY} do that to me using NTP + --hctosys, once.
// My own time zone is (most of the year) exactly one hour past GMT.
}
// This is safe (we move unsecurity-ward):
$_POST = $_SESSION['data'];
unset($_SESSION['data'], $_SESSION['data.timestamp']);
// keep things clean.
// From here on, the script behaves "as if" it got a _POST.
Update
You can actually merge save.php and datadestination.php and use a "saving stub" savepost.php that you can recycle in other pages:
<?php
session_start();
// DO NOT just copy from _POST to _SESSION,
// as it could allow a malicious user to override security.
// Use a disposable variable key, such as "data" here.
if (array_key_exists('data', $_POST)) {
// Timestamp sent by AJAX
if (array_key_exists('ts', $_POST)) {
// TODO: verify ts, but beware of time zones!
$_SESSION['data'] = $_POST['data'];
Header("Content-Type: application/json;charset=UTF-8");
die(json_encode(array('status' => 'OK')));
}
die("Error");
}
// This is safe (we move unsecurity-ward):
$_POST = $_SESSION['data'];
unset($_SESSION['data']); // keep things clean.
?>
Now your call becomes
$.post('datadestination.php', { data: list, ts: Date.now() }, function(){
window.open('datadestination.php');
});
and in your datadestination.php (or anywhere else) you add
require 'savepost.php';

I suggest:
Pass that list with the jquery.post() function and save it in the SESSION array.
Open a new tab with the same file/address/URL with the window.open() function.
Retrieve saved data from the SESSION array.
This seems straightforward and clean to me.

Passing a JavaScript value to PHP on completion of quiz

I have a web page that allows users to complete quizzes. These quizzes use JavaScript to populate original questions each time it is run.
Disclaimer: JS Noob alert.
After the questions are completed, the user is given a final score via this function:
function CheckFinished(){
var FB = '';
var AllDone = true;
for (var QNum=0; QNum<State.length; QNum++){
if (State[QNum] != null){
if (State[QNum][0] < 0){
AllDone = false;
}
}
}
if (AllDone == true){
//Report final score and submit if necessary
NewScore();
CalculateOverallScore();
CalculateGrade();
FB = YourScoreIs + ' ' + RealScore + '%. (' + Grade + ')';
if (ShowCorrectFirstTime == true){
var CFT = 0;
for (QNum=0; QNum<State.length; QNum++){
if (State[QNum] != null){
if (State[QNum][0] >= 1){
CFT++;
}
}
}
FB += '<br />' + CorrectFirstTime + ' ' + CFT + '/' + QsToShow;
}
All the Javascript here is pre-coded so I am trying my best to hack it. I am however struggling to work out how to pass the variable RealScore to a MySql database via PHP.
There are similar questions here on stackoverflow but none seem to help me.
By the looks of it AJAX seems to hold the answer, but how do I implement this into my JS code?
RealScore is only given a value after the quiz is complete, so my question is how do I go about posting this value to php, and beyond to update a field for a particular user in my database on completion of the quiz?
Thank you in advance for any help, and if you require any more info just let me know!

Storing data using AJAX (without JQuery)
What you are trying to do can pose a series of security vulnerabilities, it is important that you research ways to control and catch these if you care about your web application's security. These security flaws are outside the scope of this tutorial.
Requirements:
You will need your MySQL database table to have the fields "username" and "score"
What we are doing is writing two scripts, one in PHP and one in JavaScript (JS). The JS script will define a function that you can use to call the PHP script dynamically, and then react according to it's response.
The PHP script simply attempts to insert data into the database via $_POST.
To send the data to the database via AJAX, you need to call the Ajax() function, and the following is the usage of the funciton:
// JavaScript variable declarations
myUsername = "ReeceComo123";
myScriptLocation = "scripts/ajax.php";
myOutputLocation = getElementById("htmlObject");
// Call the function
Ajax(myOutputLocation, myScriptLocation, myUsername, RealScore);
So, without further ado...
JavaScript file:
/**
* outputLocation - any HTML object that can hold innerHTML (span, div, p)
* PHPScript - the URL of the PHP Ajax script
* username & score - the respective variables
*/
function Ajax(outputLocation, PHPScript, username, score) {
// Define AJAX Request
var ajaxReq = new XMLHttpRequest();
// Define how AJAX handles the response
ajaxReq.onreadystatechange=function(){
if (ajaxReq.readyState==4 && xml.status==200) {
// Send the response to the object outputLocation
document.getElementById(outputLocation).innerHTML = ajaxReq.responseText;
}
};
// Send Data to PHP script
ajaxReq.open("POST",PHPScript,true);
ajaxReq.setRequestHeader("Content-type","application/x-www-form-urlencoded");
ajaxReq.send("username="username);
ajaxReq.send("score="score);
}
PHP file (you will need to fill in the MYSQL login data):
<?php
// MYSQL login data
DEFINE(MYSQL_host, 'localhost');
DEFINE(MYSQL_db, 'myDatabase');
DEFINE(MYSQL_user, 'mySQLuser');
DEFINE(MYSQL_pass, 'password123');
// If data in ajax request exists
if(isset($_POST["username"]) && isset($_POST["score"])) {
// Set data
$myUsername = $_POST["username"];
$myScore = intval($_POST["score"]);
} else
// Or else kill the script
die('Invalid AJAX request.');
// Set up the MySQL connection
$con = mysqli_connect(MYSQL_host,MYSQL_user,MYSQL_pass,MYSQL_db);
// Kill the page if no connection could be made
if (!$con) die('Could not connect: ' . mysqli_error($con));
// Prepare the SQL Query
$sql_query="INSERT INTO ".TABLE_NAME." (username, score)";
$sql_query.="VALUES ($myUsername, $myScore);";
// Run the Query
if(mysqli_query($con,$sql))
echo "Score Saved!"; // Return 0 if true
else
echo "Error Saving Score!"; // Return 1 if false
mysqli_close($con);
?>

I use these function for ajax without JQuery its just a javascript function doesnt work in IE6 or below. call this function with the right parameters and it should work.
//div = the div id where feedback will be displayed via echo.
//url = the location of your php script
//score = your score.
function Ajax(div, URL, score){
var xml = new XMLHttpRequest(); //sets xmlrequest
xml.onreadystatechange=function(){
if (xml.readyState==4 && xml.status==200){
document.getElementById(div).innerHTML=xml.responseText;//sets div
}
};
xml.open("POST",URL,true); //sets php url
xml.setRequestHeader("Content-type","application/x-www-form-urlencoded");
xml.send("score="score); //sends data via post
}
//Your PHP-script needs this.
$score = $_POST["score"]; //obtains score from POST.
//save your score here
echo "score saved"; //this will be displayed in the div set for feedback.
so call the javascript function with the right inputs, a div id, the url to your php script and the score. Then it will send the data to the back end, and you can send back some feedback to the user via echo.

Call simple a Script with the parameter score.
"savescore.php?score=" + RealScore
in PHP Side you save it
$score = isset ($_GET['score']) ? (int)$_GET['score'] : 0;
$db->Query('INSERT INTO ... ' . $score . ' ...');
You could call the URL via Ajax or hidden Iframe.
Example for Ajax
var request = $.ajax({
url: "/savescore.php?score=" + RealScore,
type: "GET"
});
request.done(function(msg) {
alert("Save successfull");
});
request.fail(function(jqXHR, textStatus) {
alert("Error on Saving");
});

Request timeout

I'm using some jQuery to display tweets but once the Twitter API limit is reached, the request is sent but just keeps loading and loading. This doesn't look good. I want to be able to determine if the request is taking too long and then obviously do stuff, like cancel the request, change the styling, etc.
So this is the code that sends the request:
var fileref = document.createElement('script');
fileref.setAttribute("type","text/javascript");
fileref.setAttribute("src", "http://search.twitter.com/search.json?q="+buildString+"&callback=TweetTick&rpp=50");
document.getElementsByTagName("head")[0].appendChild(fileref);
And this is the TweetTick function:
function TweetTick(ob)
{
var container=$('#tweet-container');
container.html('');
$(ob.results).each(function(el){
/* in here, a div is built for each tweet and then appended to container */
});
container.jScrollPane(); /* just adds the scrollbar */
}

You need to cache twitter api response on your server side.
How do I keep from running into the rate limit?

I had a very similar problem lately. I use this script by Remy Sharp for most of my twitter requests: http://remysharp.com/2007/05/18/add-twitter-to-your-blog-step-by-step/
What you need to realise is that the api timeout is per IP address. So if the api has timed out for you based on your testing, it won't have timed out for someone else on a different IP address. Now, if someone accessing the site is doing so within a corporation or business, and others in the same place are doing the same, that timeout will occur almost instantaneously.
To get around this you need to cache your results. The way I did this was as follows.
I created a twitter caching system using the following code:
$twitter_username = "tadywankenobi"; //
$number_of_tweets = "10";
$options[CURLOPT_URL] = 'http://api.twitter.com/1/statuses/user_timeline.xml?screen_name='.$twitter_username.'&count='.$number_of_tweets.'&include_rts=1';
$options[CURLOPT_PORT] = 80;
$options[CURLOPT_FOLLOWLOCATION] = true;
$options[CURLOPT_RETURNTRANSFER] = true;
$options[CURLOPT_TIMEOUT] = 60;
$tweets = cache($options);
$twxml = new SimpleXMLElement($tweets);
echo "<ul>";
for($i=0;$i<=($number_of_tweets-1);$i++){
$text = $twxml->status[$i]->text;
echo "<li>".auto_link_twitter($text)."</li>";
}
echo "</ul>";
function cache($options) {
$cache_filename = "/var/cache/tweets.xml";
if(!file_exists($cache_filename)){
$handle = fopen($cache_filename, 'w') or die('Cannot open file: '.$my_file);
fclose($handle);
}// Check if cache file exists and if not, create it
$time_expire = filectime($cache_filename) + 60*60; // Expire Time (1 hour) // Comment for first run
// Set time to check file against
if(filectime($cache_filename) >= $time_expire || filesize($cache_filename) == 0) {
// File is too old or empty, refresh cache
$curl = curl_init();
curl_setopt_array($curl, $options);
$response = curl_exec($curl);
curl_close($curl);
if($response){
file_put_contents($cache_filename, $response);
}
else{
unlink($cache_filename);
}
}else{
$response = file_get_contents($cache_filename);
}
return $response;
}
What the cache function at the end does is create a file on the server and stores the twitter xml feedback in there. The system then checks to see the age of that file and if it's younger than an hour old, it takes its results from there. Otherwise, it re-accesses twitter. You need to have the file writable in the /var/cache folder (create it if it's not there).
I've kinda hacked this code together a bit, so let me know if you run into any issues with it. It also uses an auto_link_twitter() function, which creates the links required within the twitter text. I didn't write that, so I'll try and find you a link to it now.
Hope that all helps,
T
UPDATE: I can't remember where I got the auto_link_twitter() function, so here it is. If the person who wrote it reads this post, my apologies, I couldn't find the source again.
function auto_link_twitter($text) {
// properly formatted URLs
$urls = "/(((http[s]?:\/\/)|(www\.))?(([a-z][-a-z0-9]+\.)?[a-z][-a-z0-9]+\.[a-z]+(\.[a-z]{2,2})?)\/?[a-z0-9._\/~#&=;%+?-]+[a-z0-9\/#=?]{1,1})/is";
$text = preg_replace($urls, " <a href='$1'>$1</a>", $text);
// URLs without protocols
$text = preg_replace("/href=\"www/", "href=\"http://www", $text);
// Twitter usernames
$twitter = "/#([A-Za-z0-9_]+)/is";
$text = preg_replace ($twitter, " <a href='http://twitter.com/$1'>#$1</a>", $text);
// Twitter hashtags
$hashtag = "/#([A-Aa-z0-9_-]+)/is";
$text = preg_replace ($hashtag, " <a href='http://twitter.com/#!/search?q=%23$1'>#$1</a>", $text);
return $text;
}

You can use specific jQuery methods to make a JSONP request. There is basic $.ajax method and shorthand method $.getJSON which fits better for you. To control timeout of the request you can use timeout parameter. Request exceeded timeout can be processed using the error callback.
$.ajax(
dataType: 'jsonp',
url: 'http://search.twitter.com/search.json',
data: {
q: buildString,
rpp: 50
},
jsonpCallback: 'TweetTick',
timeout: 30000,
error: function(jqXHR, textStatus, errorThrown) {
if (textStatus == 'timeout') {
alert('timeout exceeded');
}
}
);