I am currently writing an ajax-application, which gets some of its config-params by sessions.
The session['apps']['appXY'], which is holding these params, is built in the php-script, which provides the js-links, calling the ajax. As i dont want the sessions['apps']['appXY'] consume resources, when the user doesnt use the ajax-app, i have the session['apps'] array deleted each time, the user calls any site by regular/synchron way.
The order of the site-buildup is like this:
session['apps'] is deleted;
app-classes are included
within each app (f.e. appXY), if needed for ajax, the session['apps']['appXY'] is built (Step3)
site is built, loading is complete, user is calling some ajax-functionality, which may depend on the session['apps']['appXY']
The Problem with this now, if at the beginning of the sites building process the session['apps'] is deleted, that the session-array $session['apps']['appXY'] is not available within the ajax-script anymore, even though, it was rebuilt - and is existing and usable - in step3, the regular php-script of appXY.
If i dont delete the session its available by ajax too, but i dont understand, why is the session not available in the ajax-application, as the deleting of it is before the rebuilding? What could cause the fact, that session is available in regular php-script, but not in ajax, after deleting and rebuilding it?
Thanx, Jayden
As suggested by Ninsuo, i try to make the szenario more clearly by a more detailed model, containing some code:
In the main-class, before including any of the modules (apps) all ajax-sessions are deleted:
function get-apps()
{
unset($_SESSION['ajaxconf']);
require_once(appXY.php);
require_once(appABC.php);
}
Then, in class 'appXY.php' the session '$_SESSION['ajaxconf']['appXY']' is (re)filled:
class appXY extends base
{
function main ( $localconf, $lang )
{
foreach ($array as $key => $value)
$_SESSION['ajaxconf']['appXY'][$key] = $value;
return 'click
}
}
Getting the values from '$_SESSION['ajaxconf']['appXY']' works fine in the ajax-script, which is called by the javascript-function 'ajax-app()', as long as the the session is not deleted at the beginnning of the php function 'get-apps()'. If the session is deleted though, its not available in the ajax-file, even though, it has been redefined again in the class 'appXY', which clearly is included after deleting the sessions. to me, this doesnt make much sense, as the session is available in the class 'appXY'.
Related
Im looking for an elegant way to hand over data/params when using $f3->reroute();
I have multiple routes configured in a routes.ini:
GET #sso: /sso/first [sync] = Controller\Ccp\Sso->first, 0
GET #map: /map [sync] = Controller\MapController->second, 3600
Now I reroute(); to #map route, from first();
class Sso {
public function first($f3){
$msg = 'My message!';
if( !empty($msg) ){
$f3->reroute('#map');
}
}
}
Is there any "elegant" way to pass data (e.g. $msg) right into $MapController->second(); ?
I don´t want to use $SESSION or the global $f->set('msg', $msg); for this.
This isn't an issue specific to fat-free-framework, but web in general. When you reroute, you tell the browser to redirect the user's browser page using a 303 header redirect code.
Take a minute to read the doc regarding re-routing: http://fatfreeframework.com/routing-engine#rerouting
There seems to be some contradicting information in your question, which leads me to question the purpose of what you are trying to achieve.
If you are rerouting, you can either use the session, cookies, or use part of the url to pass messages or references to a message.
If you do not need to redirect, but just want to call the function without changing the passed parameters, you could abstract the content of the function and call that function from both routes. You could also use the $f3 globals, which are a great way of passing data between functions in cases where you don't want to pass the data using the function call. is there a reason why you don't want to to use this? The data is global for the single session, so there is no security concern, and the data gets wiped at the end of the request, so there is very little extra footprint or effect on the server.
If you're alright with not using #map_name in re-routes you can do something like this:
$f3->reroute('path/?foo=bar');
Not the prettiest I'll admit. I wish $f3->reroute('#path_name?foo=bar') would work.
I have a PHP script that can take a few minutes to be done. It's some search engine which executes a bunch of regex commands and retrieve the results to the user.
I start by displaying a "loading page" which does an AJAX call to the big processing method in my controller (let's call it 'P'). This method then returns a partial view and I just replace my "loading page" content with that partial view. It works fine.
Now what I would like to do is give the user some information about the process (and later on, some control over it), like how many results the script has already found. To achieve that, I do another AJAX call every 5 seconds which is supposed to retrieve the current number of results and display it in a simple html element. This call uses a method 'R' in the same controller as method 'P'.
Now the problem I have is that I'm not able to retrieve the correct current number of results. I tried 2 things :
Session variable ('file' driver) : in 'P' I first set a session variable 'v' to 0 and then update 'v' every time a new result is found. 'R' simply returns response()->json(session('v'))
Controller variable : same principle as above but I use a variable declared at the top of my controller.
The AJAX call to 'P' works in both cases, but everytime and in both cases it returns 0. If I send back 'v' at the end of the 'P' script, it has the correct value.
So to me it looks like 'R' can't access the actual current value of 'v', it only access some 'cached' version of it.
Does anyone have an idea about how I'm going to be able to achieve what I'd like to do? Is there another "cleaner" approach and/or what is wrong with mine?
Thank you, have a nice day!
__
Some pseudo-code to hopefully make it a bit more precise.
SearchController.php
function P() {
$i = 0;
session(['count' => $i]); // set session variable
$results = sqlQuery(); // get rows from DB
foreach ($results as $result) {
if (regexFunction($result))
$i++
session(['count' => $i]); // update session variable
}
return response()->json('a bunch of stuff');
}
function R() {
return response()->json(session('count')); // always returns 0
}
I would recommend a different approach here.
Read a bit more about flushing content here http://php.net/manual/en/ref.outcontrol.php and then use it.
Long story short in order to display the numbers of row processed with flushing you could just make a loop result and flush from time to time or at an exact number or rows, the need for the 5 seconds AJAX is gone. Small untested example :
$cnt = 0;
foreach($result as $key => $val) {
//do your processing here
if ($cnt % 100 == 0) {
//here echo smth for flushing, you can echo some javascript, tough not nice
echo "<script>showProcess({$cnt});</script>";
ob_flush();
}
}
// now render the proccessed full result
And in the showProcess javascript function make what you want... some jquery replace in a text or some graphical stuff...
Hopefully u are not using fast_cgi, beacause in order to activate output buffering you need to disable some important features.
I believe you have hit a wall with PHP limitations. PHP doesn't multithread, well. To achieve the level of interaction you are probably required to edit the session files directly, the path of which can be found in your session.save_path global through php_info(), and you can edit this path with session_save_path(String). Though this isn't recommended usage, do so at your own risk.
Alternatively use a JSON TXT file stored somewhere on your computer/server, identifying them in a similar manner to the session files.
You should store the current progress of the query to a file and also if the transaction has been interrupted by the user. a check should be performed on the status of the interrupt bit/boolean before continuing to iterate over the result set.
The issue arises when you consider concurrency, what if the boolean is edited just slightly before, or at the same time, as the count array? Perhaps you just keep updating the file with interrupts until the other script gets the message. This however is not an elegant solution.
Nor does this solution allow for concurrent queries being run by the same user. to counter this an additional check should be performed on the session file to determine if something is already running. An error should be flagged to notify the user.
Given the option, I would personally, rewrite the code in either JSP or ASP.NET
All in all this is a lot of work for an unreliable feature.
The actual questions
How to "map" access restrictions so it can be used from php and javasript?
What kind of method should I use to share access restrictions / rules between php and javascript?
Explanation
I have created a RESTful backend using php which will use context-aware access control to limit data access and modification. For example, person can modify address information that belongs to him and can view (but not modify) address information of all other persons who are in the same groups. And of course, group admin can modify address details of all the persons in that group.
Now, php side is quite "simple" as that is all just a bunch of checks. Javascript side is also quite "simple" as that as well is just a bunch of checks. The real issue here is how to make those checks come from the same place?
Javascript uses checks to show/hide edit/save buttons.
PHP uses checks to make the actual changes.
and yes,
I know this would be much more simpler situation if I ran javascript (NodeJS or the like) on server, but the backend has already been made and changing ways at this point would cause major setbacks.
Maybe someone has already deviced a method to model access checks in "passive" way, then just use some sort of "compiler" to run the actual checks?
Edit:
Im case it helps to mention, the front-end (js) part is built with AngularJS...
Edit2
This is some pseudo-code to clarify what I think I am searching for, but am not at all certain that this is possible in large scale. On the plus side, all access restrictions would be in single place and easy to amend if needed. On the darkside, I would have to write AccessCheck and canAct functions in both languages, or come up with a way to JIT compile some pseudo code to javascript and php :)
AccessRestrictions = {
Address: {
View: [
OWNER, MEMBER_OF_OWNER_PRIMARY_GROUP
],
Edit: [
OWNER, ADMIN_OF_OWNER_PRIMARY_GROUP
]
}
}
AccessCheck = {
OWNER: function(Owner) {
return Session.Person.Id == Owner.Id;
},
MEMBER_OF_OWNER_PRIMARY_GROUP: function(Owner) {
return Session.Person.inGroup(Owner.PrimaryGroup)
}
}
canAct('Owner', 'Address', 'View') {
var result;
AccessRestrictions.Address.View.map(function(role) {
return AccessCheck[role](Owner);
});
}
First things first.
You can't "run JavaScript on the server" because Javascript is always run on the client, at the same way PHP is always run on the server and never on the client.
Next, here's my idea.
Define a small library of functions you need to perform the checks. This can be as simple as a single function that returns a boolean or whatever format for your permissions. Make sure that the returned value is meaningful for both PHP and Javascript (this means, return JSON strings more often than not)
In your main PHP scripts, include the library when you need to check permissions and use the function(s) you defined to determine if the user is allowed.
Your front-end is the one that requires the most updates: when you need to determine user's permission, fire an AJAX request to your server (you may need to write a new script similar to #2 to handle AJAX requests if your current script isn't flexible enough) which will simply reuse your permissions library. Since the return values are in a format that's easily readable to JavaScript, when you get the response you'll be able to check what to show to the user
There are some solutions to this problem. I assume you store session variables, like the name of the authorized user in the PHP's session. Let's assume all you need to share is the $authenticated_user variable. I assume i'ts just a string, but it can also be an array with permissions etc.
If the $authenticated_user is known before loading the AngularJS app you may prepare a small PHP file whish mimics a JS file like this:
config.js.php:
<?php
session_start();
$authenticated_user = $_SESSION['authenticated_user'];
echo "var authenticated_user = '$authenticated_user';";
?>
If you include it in the header of your application it will tell you who is logged in on the server side. The client side will just see this JS code:
var authenticated_user = 'johndoe';
You may also load this file with ajax, or even better JSONP if you wrap it in a function:
<?php
session_start();
$authenticated_user = $_SESSION['authenticated_user'];
echo <<<EOD;
function set_authenticated_user() {
window.authenticated_user = '$authenticated_user';
}
EOD;
?>
I'm having a multiplayer server that's using PHPSockets, and thus is written entirely in PHP.
Currently, whenever I'm making any changes to the PHP server-script I have to kill the script and then start it over again. This means that any users online is disconnected (normally not a problem because there aren't so many at the moment).
Now I am rewriting the server-script to use custom PHP classes and sorten things up a little bit (you don't want to know how nasty it looks today). Today I was thinking: "Shouldn't it be possible to make changes to the php source without having to restart the whole script?".
For example, I'm planning on having a main.php file that is including user.php which contains the class MyUser and game.php which contains the class MyGame. Now let's say that I would like to make a change to user.php and "reload" the server so that the changes to user.php goes into effect, without disconnecting any online users?
I tried to find other questions that answered this, the closest I got is this question: Modifying a running script and having it reload without killing it (php) , which however doesn't seem to solve the disconnection of online users.
UPDATE
My own solutions to this were:
At special occations, include the file external.php, which can access a few variables and use them however it'd like. When doing this, I had to make sure that there were no errors in the code as the whole server would crash if I tried accessing a method that did not exist.
Rewrite the whole thing to Java, which gave me the possibility of adding a plugin system using dynamic class reloading. Works like a charm. Bye bye PHP.
Shouldn't it be possible to make changes to the php source without having to restart the whole script?
[...]
I'm planning on having a main.php file that is including user.php
which contains the class MyUser
In your case, you can't. Classes can only be defined once within a running script. You would need to restart the script to have those classes redefined.
I am not too familiar with PHP but I would assume that a process is created to run the script, in doing so it copies the instructions needed to run the program and begins execution on the CPU, during this, if you were to "update" the instructions, you'd need to kill the process ultimate and restart it. Includes are a fancy way of linking your classes and files together but ultimately the processor will have that information separate from where the file of them are stored and it is ultimately different until you restart the process.
I do not know of any system in which you can create code and actively edit it and see the changes while that code is being run. Most active programs require restart to reload new source code.
Runkit will allow you to add, remove, and redefine methods (among other things) at runtime. While you cannot change the defined properties of a class or its existing instances, it would allow you to change the behavior of those objects.
I don't recommend this as a permanent solution, but it might be useful during development. Eventually you'll want to store the game state to files, a database, Memcache, etc.
How about storing your User object into APC cache while your main script loads from the cache and checks every so often for new opcode.
To include a function in the cache, you must include the SuperClosure Class. An example would be:
if (!apc_exists('area')) {
// simple closure
// calculates area given length and width
$area = new SuperClosure(
function($length, $width) {
return $length * $width;
}
);
apc_store('area', $area);
echo 'Added closure to cache.';
} else {
$func = apc_fetch('area');
echo 'Retrieved closure from cache. ';
echo 'The area of a 6x5 polygon is: ' . $func(6,5);
}
See here for a tutorial on APC.
Simple solution use $MyUser instead of MyUser
require MyUserV1.php;
$MyUser = 'MyUserV1';
$oldUser = new $MyUser('your name');
//Some time after
require MyUserV2.php;
$MyUser = 'MyUserV2';
$newUser = new $MyUser('your name');
Every declared class stay in memory but become unused when the last MyUserV1 logout
you can make them inherit from an abstract class MyUser for using is_a
You cannot include again a file with the same class, but you can do so with an array. You can also convert from array to class, if you really need to do so. This only applies to data, though, not to behavior (methods).
I don't know much about these things with the games on PC but you can try to get all the variables from your database for the user and then update the text fields or buttons using those variables
In web is using AJAX (change data without refreshing the page).Isn't one for programming?
I am working on my personal site, where I want to store my customers recent search result limited to that particular session.
I am using PHP platform and Javascripts.
Here is an example of what I am exactly looking at :
It stores your previously searched domain name for that particular session so that user can make decision by comparing those results.
Thanks.
EDIT- Well Thanks for all of your answers and suggestions.
But If you have noticed
above example
It looks like some kind of script loading a new content on the same page without refreshing it and keeping previous search content <div> as it is.
How to achieve this using javascripts or some sort of div layer ????
UPDATE START
This example uses page reload. If you want to do it without page reload, you can but you'll have to use AJAX to load new search results. But then, it's not a PHP question. I suggest looking at jquery library, as it makes it easy. Tutorials: http://docs.jquery.com/Tutorials and e.g. this one ( http://docs.jquery.com/Tutorials:Getting_Started_with_jQuery#Rate_me:_Using_Ajax ).
When loading data via AJAX, the page rendering result (in my example search.php) should return only HTML for results part, not whole HTML page. This is generally a first part of my tutorial (without session).
But I really think that AJAX in here is not really needed. Session is more reliable and allows access to your page from older / mobile browsers where not always JS works correctly.
UPDATE END
Ok then. Let's try the simple tutorial then. Sorry if too simple, but I don't know your exact level.
PHP has mechanism called sessions. In reality they are just bytes stored on server. Server knows which session is for each client by reading session cookie from client browser.
Not every page uses sessions (not every page needs it, and session uses server space, even if only temporarily), session is not enabled by default. To turn on session you use command
<?php session_start(); ?>
In most cases this is either run by PHP framework you use, or put near the top of your site. Session is definitely needed if you want to authenticate user somehow. Or in your case :)
To access session you can use superglobal $_SESSION variable (superglobal means that you can access it anywhere). It's an array, so session element will be e.g. $_SESSION['search'] etc.
As example, let's assume that your page looks like that
<html>
...
<form action="search.php" method="post">
Search: <input type="text" name="searchQuery" />
<input type="submit" value="Search" />
</form>
...
</html>
this very form will send user search to file named search.php. It can be the same file where the form resides - in simplest case when you put both your code and HTML in one file. Beginners often use this schema, although it's not advisable as result is a mess and hard to further change.
In search.php then, you'll use similar code:
<?php
if (!empty($_POST['searchQuery'])) //we have a new search
{
$result = do_search($_POST['searchQuery']);
}
?>
Then, somewhere below you'll display your search result ($result variable). do_search() function is your search mechanism, I guess you have it somewhere. You may have it not 'wrapped' in a function, then I advise to create it like that, it's much more useful.
function do_search($searchQuery)
{
...
return $result;
}
mind it, the above code doesn't use sessions yet. Let's add saving previous search results in session. The code may then look like that:
<?php
session_start(); //Starting session
//let's create session variable used to store results
if (!isset($_SESSION['searches']))
$_SESSION['searches'] = array();
if (!empty($_POST['searchQuery'])) //we have a new search
{
if (isset($_SESSION['searches'][$_POST['searchQuery']]) //User already searched on this value, delete previous result from sesion
{
unset($_SESSION['searches'][$_POST['searchQuery']]);
}
$result = do_search($_POST['searchQuery']);
//Let's add new search on the begining of session array to make iterations easier.
$result = array($_POST['searchQuery'] => $result); //convert result to same format as session table
$_SESSION['searches'] = array_merge($result, $_SESSION['searches']);
}
?>
In display you'll now not iterate on $result variable as before, but instead you will do something like
foreach ($_SESSION['searches'] as $query => $result)
{
...//display of single result
}
I haven't tested following code and it's not a full program. Parts to display result and to do actual search are not described but I guess you have them already prepared. Also, this is only one possible approach of countless possibilities. But I hope this helps :)
Possible modification - now I always perform search, even if user already searched on this term. You may want to receive the result from cache without second search. Then the code will look like
if (isset($_SESSION['searches'][$_POST['searchQuery']]) //User already searched on this value
{
$result = $_SESSION['searches'][$_POST['searchQuery']];
unset($_SESSION['searches'][$_POST['searchQuery']]);
}
else
{
$result = do_search($_POST['searchQuery']);
}
For more in-depth information about sessions and some other constructs used in my example I suggest PHP manual
http://pl.php.net/manual/en/book.session.php
and various tutorials over the network. Or you can add a comment here :)
Put this code near the beginning of your script(s):
if (!isset($_SESSION['previous_searches']) || !is_array($_SESSION['previous_searches'])) {
$_SESSION['previous_searches'] = array();
}
[edit]
This code snippet checks if if there is already an array with prevous searches and if not it will be created.
[/edit]
Then when the user hits the search page put this code in the receiving script of the search:
$_SESSION['previous_searches'][] = $_GET['what_ever_your_search_value_might_be'];
[edit]
This code snippet adds the current search value to the and of the array with previous search values
[/edit]
Now you have all previous search values in $_SESSION['previous_searches']
If your website is a web application where you never reload the page nor change the page, you can keep it JavaScript in a global store (declare at top level something like var StoredSearch = []; and use it). If not, then use $_SESSION to store this and AJAX to save/load searches from JavaScript to PHP.