PHP Session Is Empty On Callback Page

2
votes

I have a duplicate of a live Wordpress site on my local using Xampp. My session path in php.ini is session.save_path = "C:\xampp\tmp", and the file setting these session variables are below. After I set the session and redirect the session is empty on the callback page. What am I missing? The folder is visible in Xammp for the tmp folder.

I also have my host file pointing the Domain Url to my localhost if that matters.

session_start();

 $_SESSION['oauth_token'] = $request_token['oauth_token'];  
 $_SESSION['oauth_token_secret'] = $request_token['oauth_token_secret'];

Also it isn't working on the live site.

2
phpsession
Any error messages in the error log? - jeroen
Are you doing session_start() also on the callback page? - Jon
Is the domain in the URL for the callback page somehow different? i.e. the site is at http://example.com and the redirected page is at http://www.example.com. - PureForm

2 Answers

9
votes

Make sure that you're calling session_start() before you attempt to use the session variables on your landing page. When you redirect, you cause the browser to send a new request for a new page. This new request doesn't yet have access to the session you were using in the initial request. Calling session_start() recovers the session so you can use the data contained within it.

e.g.

FirstFile.php:

 session_start();
 $_SESSION['my_variable'] = "my data";
 header("Location: http://example.com/SecondFile.php");

SecondFile.php:

 session_start(); // **This line recovers the session**
 echo $_SESSION['my_variable']; // This line will now print "my data"
1
votes

You can avoid having to do session_start() in WordPress before having to read/write $_SESSION. Just do this in your plugin or theme's functions.php file:

if (!session_id()) {
  add_action('init','session_start');
}

Note also that if you are using the following before you call a session_start(), it will work in many PHP applications, but will cause WordPress to ERASE your session variable for some odd reason:

session_set_cookie_params(0,'/');

So, I eliminated that statement and now use the trick in the functions.php, and now my plugins and themes support sessions just fine.