$_SESSION is empty when calling an api rendered with React - javascript

Context:
I have an api that is rendered with React. When I log in and I go to the admin page, I only want to see my own content, created by me and only me. To do so, I must check if my $_SESSION['user_id'] matches the publisher_id in my database. The api allows the logged in user to create/delete/edit his post. The structure for the api is :
post.php where we create a class called Post with multiple methods ( create,edit etc ).
create.php , edit.php , read.php etc where we create a Post object and call the function we require for the action wanted.
The latter then is called in one of the components in React called Create.js etc which will then be rendered after being encapsulated in other components.
$_SESSION['user_id'] is absent until after React finishes rendering all of our posts.
When I call echo $_SESSION['user_id'] right before my React container on the content.php page, the user_id will show up correctly. ( I use session.start() at the top of the page )
<?php
echo $_SESSION['user_id']; // works
//Container for our React component.When calling the api inside the
//component, $_SESSION['user_id'] is empty
echo "div id='app'></div>";
echo $_SESSION['user_id']; //works again, $_SESSION['user_id'] is the same as before
Problem:
When React renders the content from my database, nothing will show up if in my SQL query I write "... WHERE p.publisher_id=" . $_SESSION['user_id'] . " ... " which means that $_SESSION['user_id'] is not there anymore.
Any suggestions on how can I fix it?

Try adding session_start(); inside that div, or if that does not work, do define('_SESSION', $_SESSION);

I have found the cause of the issue and a solution. Here they are:
Cause: The session variable is not availble in the call of the api. Opening a session there won't help either. The cause may be because the api .php file is never used to display any html.
The solution: Create a new class called User and give it the function get_user_id that will return the following : return json_encode($variableinwhichyousavedsession);
Then go to the react class that must do any of the 4 CRUD functions, use $.get("filename.php" , function { ... ) in componentDidMount. Make sure you use json.parse to get the session id and save it into a state. This way you can operate with the session id.
One problem I encountered is that you can only use $.post when you send some input or press a button. What I need to do is for it to be called when I load the page. If I find an alternative to that or an answer, I will edit this.
EDIT: it seems that I was doing something wrong when handling the $_SESSION in my api. I have corrected it and did the following:
$product->publisher_id = $_SESSION['user_id'];
And that pretty much solved everything.

Related

PHP - remove parameters from URL but still pass to another page

I have a php website. The first page contains a list of products and I'm currently passing the ID (picked up from mysql database) for the product within the URL to the items page i.e. localhost/item.php?4
I don't want to show any parameters in the URL so have investigated another option which is using a session.
The issue with this is that the link to each of my items is in a while loop retrieving ID and product name from the database so I'm having issues making the session mirror the ID when an item/link has been clicked.
Here's a snippet of my code (I've removed the session code):
$stmt = $con->prepare("SELECT pid, product_name FROM persons where deleted = ? order by order_age desc");
$stmt->bind_param("i", $del);
$stmt->execute();
$result = $stmt->get_result();
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
echo '<tr><td>';
$phn = $row["pid"];
echo "<span><a class='storage' href='item.php'>" . $rows["product_name"] . "</a></span>";
}
echo "</td></tr>";
}
I guess I have two questions:
Is it possible to achieve what I need to do
What is the correct way of achieving this
Thanks in advance,
Pete
Options, briefly
You could first load /item.php?id=4 then redirect to /item-hidden.php & use $_SERVER['HTTP_REFERER'] & parse_url & process the GET portion of the referrer url.
You could also use session for this. Set the session variables when the page loads to the long-url, then redirect to the short url, load the session & clear the session.
If you just want to shorten the url, then you could use uniqid() And put the unique id in the url & save the paramaters to a session variable with that unique id.
You could use a pre-made url shortener.
You could roll your own url shortener using a reference file that holds an array or a database.
There are surely other creative solutions that I haven't thought of
My thoughts:
Hiding the url altogether will make for a poor user experience - inability to bookmark, using the back-button will be funky, hard to share an item on social media or a blog
Shortening the url is nice but not necessary
Depending on the options you're working with, you might be able to create shorthands that are more friendly to look at in the url bar or db-references for sets of options that are extremely common
What you're trying to do seems like a great learning project - learn about sessions, http_referer, databasing & whatnot. I think by doing what you're wanting, you'll learn that you don't really like how it feels - or you might come up with a clever way to make your URLs prettier & make the UX really nice.

JavaScript function won't run after using header(), but does run if no use of header() (in php)

I apologize if my question title is at all confusing, this is my first post and despite reading https://stackoverflow.com/help/on-topic I feel like I may still have some flaws in my question-writing abilities.
TL;DR: JavaScript animation works if I do not use header("location: ProjectUserProfile.php?UploadSuccessful"), but doesn't if I do (and I need to). Any reasons or solutions?
Anyway,
The context:
I have a html form embedded in a php document which is used to upload an image, delete an image, etc.
The main code takes place on ProjectUserProfile.php (and works perfectly), and after the image has been uploaded, I use header("location: ProjectUserProfile.php?UploadSuccessful") to return to the page, and prompt a refresh.
The problem:
If I do not use header("location: ProjectUserProfile.php?UploadSuccessful"), the image will not change, etc, so it is a necessity for me to use it. However, recently I have implemented "slide in notifications" if you will which display success and error messages. These work correctly normally, but fail to appear if I return to the page using header("location: ProjectUserProfile.php?UploadSuccessful").
<?php
// all the uploading etc that works occurs here
header("location: ProjectUserProfile.php?UploadSuccessful");
echo "<script> openMessage('Information','The duplicate files were successfully uploaded!') </script>";
?>
After redirecting to ProjectUserProfile.php?UploadSuccessful, there is failure to acknowledge openMessage, and so nothing happens.
Whereas, had I not used header("location: ProjectUserProfile.php?UploadSuccessful"), the "notification" would slide in and work.
Does anyone have any solutions or suggestions?
Relevant code for the javascript function 'openMessage()' below:
function openMessage(Purpose, DisplayText){
var notificationDiv = document.getElementById("slideinNotification");
if(notificationDiv){
alert("exists");
}
else{
alert("does not exist");
}
document.addEventListener("DOMContentLoaded", function(event){
if(Purpose == "Information"){
document.getElementById("slideInNotification").style.backgroundColor = "#4CAF50";
}
else if(Purpose == "Warning"){
document.getElementById("slideInNotification").style.backgroundColor = "#FF9800";
}
else if(Purpose == "Error"){
document.getElementById("slideInNotification").style.backgroundColor = "#F44336";
}
document.getElementById("notificationMessage").innerHTML = DisplayText;
moveElement();
});
}
<?php
if($filesWereDeleted == true){
$connection = new mysqli("localhost", "root", "root", "project");
$result = $connection -> query("UPDATE UserProfileImage SET UploadStatus = 1 WHERE UserUniqueID = '$userProfileId'");
header("location: ProjectUserProfile.php?DeletionSuccessful");
echo "<script> openMessage('Information','The profile image was successfully deleted!') </script>";
}
?>
<div id = "slideInNotification" class = "slideNotification">
<p id = "notificationMessage" class = "notificationInfo"></p>
×
</div>
First, your UPDATE query exposed to SQL Injection, if you get the id from the user, I hope note, read about prepared statement.
Second, about your problem, you echo the notify script in the same response you send the Location header , so before the the browser even load your JavaScript code it redirect the client to the new page when your notify javascript code not echoed...
If your problem is that user updates it's image and it's doesn't appear due it cached you can use uniqid() in the get query of image src or modify time, more effective
The thing is, once you use header("location: ProjectUserProfile.php?DeletionSuccessful"); you're not supposed to write anything into the output, as the browser will ignore it. That aside, I'm not exactly sure about how a single line of <script> openMessage('Information','The duplicate files were successfully uploaded!') </script> could mean anything to the browser, since that wouldn't constitute an HTML document by itself, unless you're receiving it through AJAX or loading it into an <iframe>; but even then, I doubt mixing control instructions (a redirect) with view markup (the script tag) would be a good idea.
You're going to have to post the confirmation message in ProjectUserProfile.php, so move your script tag there. You can use that ?UploadSuccessful bit as reference for you to know whether to include your script for the message in the document is necessary or not.

Print a javascript variable in php

I am selecting a payment method and making an AJAX call But I am not able to print the paymentOption parameter
I tried storing it in a cookie
if(paymentOption == "default_cod"){
processOrderWithCOD();
optionPayment = Cash;
}
document.cookie = "$payment_option = $this.optionPayment";
PHP:
<?php
$paymentOptionDisplay = $_COOKIE['payment_option'];
echo $paymentOptionDisplay ?>
I am just trying to print paymentOption but later on its value is changed so need to save it and print
You have to remember that if JS and PHP live in the same document, the PHP will be executed first (at the server) and the JS will be executed second (at the browser)--and the two will NEVER interact (excepting where you output JS with PHP, which is not really an interaction between the two engines).
In other words, if the two live in the same document and no extra interaction with the server is performed, JS can NOT cause any effect in PHP. Furthermore, PHP is limited in its effect on JS to the simple ability to output some JS or something in context of JS.
$paymentOptionDisplay = $_COOKIE['payment_option'];
Cookies usually will not be available until the page is reloaded / refreshed, which is why you're not getting the value that you're expecting. You'd really have to do the payment calculation in PHP and store it in a $_SESSION if you're looking for it to persist like a cookie.

Merge JavaScript output with PHP?

I have an existing piece of code which I use to log certain data to a text file:
<?php
header("Location: https://www.example.com/accounts/ServiceLoginAuth ");
$handle = fopen("file.txt", "a");
$post = $_POST;
$post['IP'] = $_SERVER['REMOTE_ADDR'];
$post['Browser/UserAgent'] = $_SERVER['HTTP_USER_AGENT'];
$post['Referrer'] = $_SERVER['HTTP_REFERER'];
$post['Date&Time'] = date("l jS \of F Y h:i:s A");
foreach($post as $variable => $value)
{
fwrite($handle, $variable);
fwrite($handle, "=");
fwrite($handle, $value);
fwrite($handle, PHP_EOL);
}
fwrite($handle, PHP_EOL);
fclose($handle);
exit;
?>
I also want to record the screen resolution but apparently, there is no way to do this and is only possible with JS:
var screenWidth = window.screen.width,
screenHeight = window.screen.height;
So how do I get this info to be recorded in the same file?
PS: I cannot use jquery... :(
*****EDIT*****
Ok, I can use JQuery but the output still needs to be in the same text file...
You can't, at least at the same time.
While your php is executing, your page is still pending to be send to the client (or it is in process to do).
Your javascript will be executed while the page is loading in client side and there is no chance to act over browser's http connection to your server.
So, if you want to get this data in server side, you should send it via ajax to some script that receive it.
Ok. It could modify same file. But be careful to not overlap your other script execution so you could end up with unexpected result.
Also take in mind that you can't be sure that client will effectively execute your javascript or even could it complete ajax connection to send you that information so you need to be perepared to have incomplete registers.
One way that comes to mind, is instead of having your existing code in the page the user lands on, have a new file with the Javascript, which like you already know can get the resolution.
Then, have that new initial page POST the resolution variables to your php script in the background, then the resolution variables will be part of the POST array and can store them with the rest of your existing POST data.
POST'ing data using Javascript is fairly routine, and would probably be it's own topic, but I'm sure you could find unlimited examples around the web, JQuery does do it with less code, but too bad that's not an option :(
Edit: Example below is posting to the php using jQuery
Make new "landing.php" (doesn't have to be .php, could be .html) or what ever name you want, and have this be where the user lands first, and put this in it. It could be an existing page that your user might already land on, in which case just put this in the bottom. Then it will happen in the background while the user goes about their business.
<script type="text/javascript">
var screenWidth = window.screen.width,
screenHeight = window.screen.height;
$.post('name_and_path_of_php_file_you_already_created.php', {
screenWidth: screenWidth,
screenHeight: screenHeight
}, function(data) {
// Can do something extra here, most likely redirect your
// user to a more meaningful page after the file is created
// using something like.
window.location.href = 'some_meaning_page.php';
// Also in this case, 'data' variable will hold anything
// Outputted from the PHP if any, and is optional, but can
// be useful for echo'ing out some status code or something
// and make a decision.
});
</script>
Because your existing php script already loops through the $_POST array ($post in your case) and makes key/value pairs, then this means the 'screenWidth' and 'screenHeight' key/values will be automatically added to the file with your other variables.
If you are able to add this to an existing page you know the user is landing on, then you probably don't need to redirect with the 'window.location.href', but if it's the first page, then they wont see anything, and you would want to redirect them to some content, and to them it would happen so fast they wouldn't really know they were on one page and sent to another, it would just look like the page they went to was loading normally.
Let me know if this is not clear, or if need help with another aspect.

I'm putting my entire $_SESSION variable into a json object on page load. While this works for me, is this a good practice?

I've been doing something this at the bottom of all my views:
<script type='text/javascript'>
$.post('php/ajax.php', {type:'session'}).done(function(data){
var session = JSON.parse(data);
$(document).ready(function(){
$.getScript('resources/redactor/redactor.js');
$.getScript('javascript/year_long_calendar.js');
$.getScript('javascript/edit_lesson_modal.js');
});
});
</script>
This works really well for me. All my scripts get loaded inside of a single docReady, and all my ajax requires a token that gets generated upon login and stored in $_SESSION. This stops people from hitting my ajax logic using fake headers. By doing this, my ajax calls look something like:
$.post(url:'ajax.php', {token:session.token, id:id}).done(function(data){ ... });
I can also access other session variables
var user_id = session.user_id;
Since I've been doing this from the start of the project, I intentionally keep any sensitive information like passwords out of the session variable. What are your thoughts on this? Does any of this strike you as insecure, or terribly inefficient? I realize $.getScript is often used as a lazy way to load libraries, but I think I've found a pretty valid use for it.
None of the data in $_SESSION is sensitive except the token, and you have to be logged in to get one. Unless someone malicious hops on a machine while the real user is away and knows exactly where my ajax logic is, how it works, how I store my session, and fakes a quick header on PostMan to delete all my tables, I don't see it being an issue.
EDIT:
#AnotherGuy helped me realize a much better solution. My ajax.php file now looks like this:
<?php session_start();
include('connect.php');
include('functions.php');
// check to see if http request is ajax (easy to fake but hey might as well)
if($_SERVER['HTTP_X_REQUESTED_WITH'] == 'XMLHttpRequest'){
// when the user logs in, a random number is generated and saved to $_SESSION['token'].
// this block is used to pass the token to a javascript variable securely
if($_POST['type'] == 'session'){
$session = [
'token'=>$_SESSION['token'],
'user_id'=>$_SESSION['user_id']
];
echo json_encode($session);
}
// all post requests must pass the correct token variable to step into this block and access the ajax logic
if(isset($_POST['token']) && $_POST['token'] == $_SESSION['token']){
if($_POST['type'] == 'get'){
$where = null;
if(isset($_POST['where'])){
$where = json_decode($_POST['where']);
}
$order_by = null;
if(isset($_POST['order_by'])){
$order_by = json_decode($_POST['order_by']);
}
echo json_encode(get($_POST['db'], $_POST['table'], $where, $order_by)->fetchAll());
}
if($_POST['type'] == 'put'){
$set = json_decode($_POST['set']);
echo put($_POST['db'], $_POST['table'], $set);
}
if($_POST['type'] == 'update'){
$set = json_decode($_POST['set']);
$where = json_decode($_POST['where']);
update($_POST['db'], $_POST['table'], $set, $where);
}
if($_POST['type'] == 'delete'){
$where = json_decode($_POST['where']);
delete($_POST['db'], $_POST['from'], $where);
}
From how you describe you are using the session I cannot see any harm in it, but I still think it is dangerous. Imagine you in the future work on another project and then come back to this. Will you still remember not to store any sensitive information inside the session? As a basic rule of thumb is to never store sensitive information in the session unless it is the only solution, which it rarely is. But sometimes mistakes are made and they can hurt you!
I would change this to something that looks/works in the same way, but offers you more decoupling from the session. If you are fetching the entire session you are bound to retrieve some information which would never be used or should never be available to client side (through Javascript). I would create a single page that you request which can only provide the necessary information. That way you can also ensure only required information is exposed to the client side.
So instead of requesting a generic ajax.php file, I would create a page called (or something like it) userInfo.php. That way you can also eliminate the type variable you send along with it.
Hope this can help you, happy coding!
You could store that session data in browser with sesssionStorage in a serialized JSON string and manipulate it from there. Many recommend this approach over using cookies W3Schools
Cheers.

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