There is a page, that can be visited with one of three params: ref1, ref2 and ref3. Each time page script sets a couple of cookies to store ref-param and time of it's creation. After that it should find the latest one and be ready to deal with it.
For example if I have "ref1" cookie as latest before visiting page and visit
script.php?ref2=1
it should echo
latest is ref2
But it works properly (echoes right latest cookie) only after additional reloading of the page. What's wrong with this code?
if ($_GET['ref1']) {
setcookie('ref1', 'ref1');
setcookie('ref1_dt', time());
}
if ($_GET['ref2']) {
setcookie('ref2', 'ref2');
setcookie('ref2_dt', time());
}
if ($_GET['ref3']) {
setcookie('ref3', 'ref3');
setcookie('ref3_dt', time());
}
function getLatestCookie() {
$refs = array(
'ref1' => $_COOKIE['ref1_dt'],
'ref2' => $_COOKIE['ref2_dt'],
'ref3' => $_COOKIE['ref3_dt']
);
$maxs = array_keys($refs, max($refs));
return $maxs[0];
}
$latest = getLatestCookie();
setcookie('latest', $latest, time() + 60 * 60 * 24 * 30, "/");
echo "latest is " . $latest;
As usual, reading docs was good enough.
Cookies are available in $_COOKIE array after next page loading. So in my case I should assign $latest to GET-param value if it exists and else assign it with getLatestCookie().
Related
I am working on WordPress multisite, and I have changed the login functionality. However, it needs the users to delete old cookies before using this functionality I have created. So I am trying to clear the user's cookies by setting a new cookie, custom_wordpress_login_cookie, to know which of the users have old cookies in the browser, as shown in the following code.
add_action('init', 'clear_all_cookies_before_login');
function clear_all_cookies_before_login(){
if( ! isset( $_COOKIE['custom_wordpress_login_cookie'] ) ){
foreach( $_COOKIE as $key => $value ){
setcookie( $key, '', time() - YEAR_IN_SECONDS);
}
setcookie( 'custom_wordpress_login_cookie', 'true',
time() + YEAR_IN_SECONDS, '/', COOKIE_DOMAIN, false, true );
}
}
The new cookie is being set, but the old cookies persist. What could be the issue?
To prevent creation of a second cookie with the same name, pass / as the path argument to setcookie().
And so, you must change this line:
setcookie( $key, '', time() - YEAR_IN_SECONDS);
to:
setcookie( $key, '', time() - YEAR_IN_SECONDS, '/');
Also note that the way you're expiring cookies may not work if the user's system time is configured incorrectly. This is rare*, but does happen. A simpler way to expire cookies is to simply call:
setcookie( $key, '', 1, '/');
*the user would likely run into TLS issues if the webpage is served over HTTPS.
This is not an answer related to how you can clear cookies, but this solution will help you make sure that all the users currently logged into your website will need to login again.
Go in the wp-config.php and reset the secret salt keys. You can generate new ones here: https://api.wordpress.org/secret-key/1.1/salt/ .
That way it will force all of your users to login again and you no longer need to write code to delete the users' cookies.
Try: setcookie( $key, '', time() - 3600, '/', COOKIE_DOMAIN);
According WordPress documentation, it combines the salt keys with the password. The hash function mixes these up and gives a result. After that it stores inside a cookie to "remember" the login process or tracking behavior.
example: That's the reason two different usernames with the same password are successfully identified as different logins.
First you have to make distinct cookies for every user. Let's say custom_wordpress_login_cookie will contain inside a string with the username or any associated encoded string (preferred).
Then you will check if the custom_wordpress_login_cookie exists and contains the appropriate username.
Act accordingly, if found, perform your logic and then delete (unset) the cookie. Else create a new one.
The following code explains the flow...
function clear_all_cookies_before_login() {
// Current Time of visit
$time_now = date('F j, Y g:i a');
// Check a cookie already set
if(isset($_COOKIE['custom_wordpress_login_cookie'])) {
// Found Cookie
function check_visitor() {
// Retrieve information to use for your logic
$lastvisit = $_COOKIE['custom_wordpress_login_cookie'];
$string .= 'Since your last login '. $lastvisit .'. We have a tone of new things!';
// Delete the old cookie so that we can set it again with updated time
unset($_COOKIE['custom_wordpress_login_cookie']);
return $string;
}} else {
// Not found cookie
function check_visitor() {
$string .= 'Welcome to our website! Please login...' ;
return $string;
}
}
add_shortcode('New_Message', 'check_visitor');
// Set new cookie with expiration of 1 Day
setcookie('custom_wordpress_login_cookie', $time_now , time()+86400);
}
you must used first unset
unset( $_COOKIE[$v_username] );
setcookie( $v_username, '', time() - ( 15 * 60 ) );
Once that’s done, we will force the cookie to expire by setting its value variable to a null value (“”) and passing in a timestamp that’s in the past (time() - ( 15 * 60 )).
You are doing absolutely correct but the deletion of the cookie would not work. The above code will only expire the cookie in the current session. You have to destroy the session also if you want to make the old cookie dis-appear. Thus your new code would be like this:
add_action('init', 'clear_all_cookies_before_login');
function clear_all_cookies_before_login(){
if( ! isset( $_COOKIE['custom_wordpress_login_cookie'] ) ){
foreach( $_COOKIE as $key => $value ){
setcookie( $key, '', time() - YEAR_IN_SECONDS);
}
setcookie( 'custom_wordpress_login_cookie', 'true', time() + YEAR_IN_SECONDS, '/', COOKIE_DOMAIN, false, true );
//Destroy the session and re-direct the user to other location
//this will make sure to disappear the old cookie and new cookie
//only will remain
session_destroy();
header("Location:/");
}
}
I have a webpage that refreshes every X minute and shows some information from an array.
Name Value
-------------
Mark 546
Donald 312
My question is what is the easiest way to temporarily store the old value and compare it to the new value between page refreshes (see below)? It could be per user based simply when visiting the page. Php session and cookies maybe?
Name Value Change
--------------------
Mark 559 +13
Donald 233 -79
So you can easily do it with sessions
//structure in sessions could be like this
$_SESSION['last'] = $data; // all the data you echo
$_SESSION['last']['timestamp'] = $time; //timestamp when you fetched this data
$_SESSION['previous'] = $old_data; // store the last data
// each time last data is older than 5 min, refresh
if (time() - $_SESSION['last']['timestamp'] > 5 * 60){
//store current data as previous
$_SESSION['previous'] = $_SESSION['last'];
//set new data in $data
$_SESSION['last'] = $data; // set all your new data
$_SESSION['last']['timestamp'] = time(); //set timestamp
}
On Page Variable =
$lgc_code = '1,2,3,15,23,30';
Cookie = 'lgc_cntl'
My cookie is housing logic codes for each user to determine what banners or icons should show based on previous web pages visited. I have written the following function:
$lgc=$lgc_code;
// check for variable for multiple codes
$expEncArr = explode(",", $lgc);
$results = count($expEncArr);
if(isset($_COOKIE['lgc_cntl'])) {
// read cookie
$cookie_codes = $_COOKIE['lgc_cntl'];
// Build Array of cookie codes
$expEncArr2 = explode(",", $cookie_codes);
foreach($expEncArr as $l_code) {
if(in_array($l_code, $expEncArr2)) {
$lgc_codes=$_COOKIE['lgc_cntl'];
} else {
$lgc_codes=$_COOKIE['lgc_cntl'].','.$l_code;
} // end array search statement
// add campaign to cookie
setcookie('lgc_cntl',$lgc_codes,time() + (86400 * 365), "/", ".oru.edu"); // 86400 = 1 day
} // end foreach statement
} else {
$lgc_codes = $lgc;
// add campaign to cookie
setcookie('lgc_cntl',$lgc_codes,time() + (86400 * 365), "/", ".oru.edu"); // 86400 = 1 day
} // end isset(cookie) if / else statement
If there is no cookie set, the function works perfectly but if there is a cookie found it only adds the last variable in the array versus any codes not found in the cookie already.
The function should work as follows:
Separate on-page variable into an array
Check for the cookie
Separate Cookie values into an array
Compare the variables on page to values in cookie
Add any on page variables not found in the cookie
It is working all the way through but when the cookie is set, it is only adding the last variable in the string even if none of the others are not located in the cookie array. What am I doing wrong or how can I solve this?
This is a common mistake - $_COOKIE is not affected by calling setcookie. This is because $_COOKIE is created at the beginning of the PHP script execution based on data sent from the browser, and setcookie sends data to the browser.
Consequently, each time you run this line:
$lgc_codes=$_COOKIE['lgc_cntl'].','.$l_code;
Your value of $lgc_codes is the cookie string originally sent by the browser plus exactly one extra code.
The solution is to instead use a local variable, such as $new_cookie_value, to build up the full string, and then call setcookie once:
$new_cookie_value = $_COOKIE['lgc_cntl'];
foreach($expEncArr as $l_code) {
// if statement removed to keep example brief
// Add extra code to list
$new_cookie_value = $new_cookie_value .','.$l_code;
}
// Now call setcookie once with the desired value
setcookie('lgc_cntl',$new_cookie_value,time() + (86400 * 365), "/", ".oru.edu");
[Aside: Do not underestimate the value of good variable names. Your code would be much clearer if $expEncArr and $expEncArr2 had longer names which described what the difference was between them. Similarly, $lgc, $lgc_code, $lgc_codes, etc.]
Your logic is very muddled. This is what should be in the first portion of your if block
// read cookie
$cookie_codes = $_COOKIE['lgc_cntl'];
// Build Array of cookie codes
$expEncArr2 = explode(",", $cookie_codes);
$lgc_codes = $_COOKIE['lgc_cntl'];
foreach ($expEncArr as $l_code)
{
if (!in_array($l_code, $expEncArr2))
{
$lgc_codes .= ',' . $l_code;
}
}
setcookie('lgc_cntl', $lgc_codes, time() + (86400 * 365), "/", ".oru.edu");
I would like to cache the result of the twitter api result and display them to users..
What's the best method to cache the result?
I'm thinking a writing the result into a file based on a time limit.. Is that ok or any other method should be used?
And most importantly what would be the ideal cache time ? I would like to display the latest content from the twitter but the twitter api has the request limits..
And my site has solid visitors/day..
The cleanest way to do this would be to use APC (Alternative PHP Cache) if it installed. This has a built in "time to live" functionality:
if (apc_exists('twitter_result')) {
$twitter_result = apc_fetch('twitter_result');
} else {
$twitter_result = file_get_contents('http://twitter.com/...'); // or whatever your API call is
apc_store('twitter_result', $twitter_result, 10 * 60); // store for 10 mins
}
A 10 minute timeout on the data would be my choice. This would vary depending on how frequently the feed is updated...
Edit If you don't have APC installed, you could do this using a very simple file:
if (file_exists('twitter_result.data')) {
$data = unserialize(file_get_contents('twitter_result.data'));
if ($data['timestamp'] > time() - 10 * 60) {
$twitter_result = $data['twitter_result'];
}
}
if (!$twitter_result) { // cache doesn't exist or is older than 10 mins
$twitter_result = file_get_contents('http://twitter.com/...'); // or whatever your API call is
$data = array ('twitter_result' => $twitter_result, 'timestamp' => time());
file_put_contents('twitter_result.data', serialize($data));
}
When I create a cookie, how to get cookie's expire time?
Putting an encoded json inside the cookie is my favorite method, to get properly formated data out of a cookie.
Try that:
$expiry = time() + 12345;
$data = (object) array( "value1" => "just for fun", "value2" => "i'll save whatever I want here" );
$cookieData = (object) array( "data" => $data, "expiry" => $expiry );
setcookie( "cookiename", json_encode( $cookieData ), $expiry );
then when you get your cookie next time:
$cookie = json_decode( $_COOKIE[ "cookiename" ] );
you can simply extract the expiry time, which was inserted as data inside the cookie itself..
$expiry = $cookie->expiry;
and additionally the data which will come out as a usable object :)
$data = $cookie->data;
$value1 = $cookie->data->value1;
etc. I find that to be a much neater way to use cookies, because you can nest as many small objects within other objects as you wish!
This is difficult to achieve, but the cookie expiration date can be set in another cookie. This cookie can then be read later to get the expiration date. Maybe there is a better way, but this is one of the methods to solve your problem.
You can set your cookie value containing expiry and get your expiry from cookie value.
// set
$expiry = time()+3600;
setcookie("mycookie", "mycookievalue|$expiry", $expiry);
// get
if (isset($_COOKIE["mycookie"])) {
list($value, $expiry) = explode("|", $_COOKIE["mycookie"]);
}
// Remember, some two-way encryption would be more secure in this case. See: https://github.com/qeremy/Cryptee
When you create a cookie via PHP die Default Value is 0, from the manual:
If set to 0, or omitted, the cookie
will expire at the end of the session
(when the browser closes)
Otherwise you can set the cookies lifetime in seconds as the third parameter:
http://www.php.net/manual/en/function.setcookie.php
But if you mean to get the remaining lifetime of an already existing cookie, i fear that, is not possible (at least not in a direct way).
It seems there's a list of all cookies sent to browser in array returned by php's headers_list() which among other data returns "Set-Cookie" elements as follows:
Set-Cookie: cooke_name=cookie_value; expires=expiration_time; Max-Age=age; path=path; domain=domain
This way you can also get deleted ones since their value is deleted:
Set-Cookie: cooke_name=deleted; expires=expiration_time; Max-Age=age; path=path; domain=domain
From there on it's easy to retrieve expiration time or age for particular cookie. Keep in mind though that this array is probably available only AFTER actual call to setcookie() has been made so it's valid for script that has already finished it's job. I haven't tested this in some other way(s) since this worked just fine for me.
This is rather old topic and I'm not sure if this is valid for all php builds but I thought it might be helpfull.
For more info see:
https://www.php.net/manual/en/function.headers-list.php
https://www.php.net/manual/en/function.headers-sent.php
To get cookies expire time, use this simple method.
<?php
//#############PART 1#############
//expiration time (a*b*c*d) <- change D corresponding to number of days for cookie expiration
$time = time()+(60*60*24*365);
$timeMemo = (string)$time;
//sets cookie with expiration time defined above
setcookie("testCookie", "" . $timeMemo . "", $time);
//#############PART 2#############
//this function will convert seconds to days.
function secToDays($sec){
return ($sec / 60 / 60 / 24);
}
//checks if cookie is set and prints out expiration time in days
if(isset($_COOKIE['testCookie'])){
echo "Cookie is set<br />";
if(round(secToDays((intval($_COOKIE['testCookie']) - time())),1) < 1){
echo "Cookie will expire today.";
}else{
echo "Cookie will expire in " . round(secToDays((intval($_COOKIE['testCookie']) - time())),1) . " day(s)";
}
}else{
echo "not set...";
}
?>
You need to keep Part 1 and Part 2 in different files, otherwise you will get the same expire date everytime.