I am trying to create a PHP code that will execute once every 24 hours. The current CMS that I am using supports this, and it works correctly, whereas, I want to make it a little more complicated.
For one hour, every day, I want a code to execute, which will give special permissions to my users during this one hour.
Once the hour is up, I would like it to revert the changes, taking away the permissions. The users would then need to wait until the next day, when the hour is back.
For example:
<?php
if (!defined('UBER') || !UBER)
{
exit;
}
dbquery("UPDATE catalog_pages SET visible = '1' WHERE id='91'");
$core->Mus('update_catalogue');
?>
This code executes once every 24 hours, and works fine. It updates the catalogue setting a page to be visible to everyone. I am only stuck on how to make it disappear after the hour is up.
Lets say that the hour is 4.00am to 5.00am.
How would I make the page disappear after 5.00am using a PHP code?
Thanks in advance.
if (date("G") == '4'){
//give
}elseif (date("G") == '5'){
//takeway
}
or in the query
.. WHERE HOUR(NOW()) BETWEEN 4 AND 5
This is actually really easy to do. When the user logs on or tries to use a permission that is only granted at the certain time, run a check to see if the time is within those hours. If your CMS allows you to intercept events, use something like this:
onUserAction(){
if(isSpecialHour()){
denyPermission()...
}
else{
grantPermission()...
}
}
When the user tries to do something that requires a permission, the system should check if it is within that special hour period and then either grant or deny permission.
With PHP alone, it is impossible to have a script run at a specific interval. PHP scripts are run when they are loaded, and unless you have someone run the scrip at that exact time (or use something like cron) it can not be done. Of course, you could use cron or simmilar to accomplish the same thing. The above method is probably your best bet though.
Related
I am currently working on a project that runs online tournaments. Normally admins of the site will generate brackets when it is time for the tournaments to start, but we have run into inconsistent start times, etc. and i am looking into proper ways to automate this process.
I have looked into running cronjobs every x min to check if a bracket needs to be generated but i am worried about issue when it comes to overlapping cronjobs, having to create/manage cronjobs through cpanel etc.
I was thinking about other solutions and thought it would be great if a user could load a page, the backend checks timestamps and determines if the bracket should be generated. An event is then fired/set to begin the auto-generation process elsewhere so it does not impact user load times. I just do not know the best route of going about this.
PS: I just need an idea of the direction i should be looking into so i can learn how to solve this issue i am not looking to copy and paste code. I just haven't been able to find anything. All of my search results provide cronjob examples.
EDIT
After thinking about things could using this work?
$(document).ready(function() {
$.ajax('Full Url Path Here');
})
I don't need to pass user input, or return any data i simply need a way to fire an event, it would be easy to include this only when needed via a helper class. Also i won't necessarily have to worry about users attempting to access i can restrict the route to ajax only requests and since nothing is needed/used on input or returned as output what can happen?
You could do it everytime a user loads a page (idea not tested, but theoretically possible):
1) Create a file and store the timestamp of the last time you updated the database.
2) Everytime a user loads a page, read that timestamp and check if 15 minutes passed.
3) If 15 minutes passed: Run a background script (with shell_exec?) that will do what you want and update the timestamp when it's done executing.
One obvious flaw with this system is that if you have no visitors in let's say a 30 minute frame, you will miss 2 updates. Though I guess that if you have no visitors you also have no point in generating brackets?
I am trying to create a site in PHP and MySQL where a person is assigned to do a task for another person. Time period allotted to complete the task is 72 hours.
If done, the other person will confirm so. If not, I want to take certain actions (like blocking his account, sending an email, assign the task to someone else etc.) What is the best way to do this?
As the count-down runs second-by-second, I guess I will have to run a script every second.
You could use a cronjob to check for the deadline and eventually send the email, block the account, etc...
Although, if you actually need a persecond precision, you might want to use a single process with an "infinite" cicle and some sleeps in between.
If your server is from *nix family, you could use cron/crontab. See examples of usage at: http://en.wikipedia.org/wiki/Cron and https://help.ubuntu.com/community/CronHowto
Very few things have to happen truely immediately. If you've waited 72 hours for something to happen, having an action occur within a matter of a few minutes will not matter so much.
If you really do want something to happen so quickly, and you will always have a long time between potential events, one thing I would suggest is not using a cronjob, but something more akin to what #muc has suggested - a script that runs regularly within a shell script that will keep it going (just doing an 'exec $0' at the end to rerun the script when it would exit).
The script (in PHP for example) that checks the database doesn't have to be running all the time either. Whenever it finds something that is due to happen in more than a few seconds time, it sleeps till the next event is due to happen. When it wakes up, it can double-check that it is still required, and then performs the relevant job.
<?php
$jobId = whatToRunNext();
if (! $jobId) {
exit;
}
$secsToNextJob = howLongToNextJob($jobId);
if ($secsToNextJob > 0) {
sleep($secsToNextJob);
if (! jobStillRequired($jobId)) {
exit;
}
}
doJob($jobId);
exit;
Wrap that in a shell sript that will keep it running, maybe with a small sleep in the bash script, and you'd be good - while not being in a very long-running, cpu-killing loop.
If I needed to do something like that, I would probably go by these steps:
Create event and calculate deadline
Set up a cronjob to run at the deadline time
cronjob checks the event status and takes actions
I think this will be the most efficient way in doing it.
I am trying to create a site in PHP and MySQL where a person is
assigned to do a task for another person. Time period allotted to
complete the task is 72 hours.
These could simply just be db vales
table_task
.id
.user_assigned
.strart_date
.end_date
.status
.desc
If done, the other person will confirm so. If not, I want to take
certain actions (like blocking his account, sending an email, assign
the task to someone else etc.) What is the best way to do this?
This again, Admin panel of some form with a layout of assigned jobs, the ''worker'' should be required to post a job as ''done'', the ''admin'' can then confirm this. This can all be managed via Values in the db ''table_task.status''
As the count-down runs second-by-second, I guess I will have to run a
script every second.
^-- server suicide
Run the cron ever hour at most. If you have 1000 users. Then this cron will run 1000 a sec
in an hour this is, 60000*60
If you need to display the time use some jQuery of some form. There are lots of clock scripts.
Any of the users can trigger an event, as many times they wish. Each time this event is triggered, a row in a mysql table is created with the timestamp, their userid and other useful information. What I need to do is launch a script which runs exactly 12 hours after the event is triggered i.e. for each row in the table.
How can I achieve this in an automated and efficient fashion?
You could use a cron job which every minute launches the script.
In the script you should first fetch the row(s) and check if it's OK to run (if 12 hours passed) then continue, else stop.
I don't know if this will be very efficient, it depends on your number of entries in the database, but technically it's not expensive to just check if the current date matches a date fetched from the database + 12 hrs, I cannot say more because you didn't give too much details about your data.
You'd probably be better off with a cronjob
http://en.wikipedia.org/wiki/Cron
Potentially, you could look into MySQL event scheduler. Although It might not fit your needs, hard to really tell on the details given
http://dev.mysql.com/doc/refman/5.1/en/events.html
something like
CREATE EVENT myTimedEvent ON SCHEDULE EVERY INTERVAL 5 minutes DO CALL updateRows();
updateRows checks your criteria (12hours ago), if it is, perform whatever action you want to do. This requires your MySQL to be # version 5.1+ however
You would probably best have a cron job which runs every minute and checks for any rows in the database > 12 hours old that have not yet been processed the script and process them. This wont give you EXACTLY a 12 hour difference, but would give you a difference within a minute of that.
You would probably also want to make sure that script would be able to run within a few seconds such that you don't have overlap of the script running twice at the same time.
This could be done using CronJobs. If you have root access to your Server or a server administration toolkit that offers cronjob managment you would do it on your server. otherwise use an online cronjob service (google for cronjob online).
the cronjob then triggers a php script on your server in your defined interval, like every minute or every 5 minutes.
this script then selects all rows from your mysql table which are older then 12 hours (WHERE timestamp <= NOW() - INTERVAL 12 hour ) and performs your desired actions on each result and delete the result from the table (or mark it done),
just make sure that the fetching and the actions itself are faster than your cronjob interval, otherwise you would have two or more scripts working on the same rows.
The easy way for me is to make the page head contains
<head>
<meta http-equiv="refresh" content="43200"> <!-- 43200 for (12 hours × 60 mintes × 60 seconds) -->
</head>
This method is very helpful to avoid server time out, which you can't avoid if you are using only PHP code
Important if you start the script using submit button, it's recommended to make the form action="other_page" not the same page, and sure you should save your input values as cookie using setcookie function and grab it as a variable in the action page using $cookieVar = $_COOKIE['the_cookie_name'] ;
You may need to increase or decrease the $cookieVar value and update the value again using setcookie every time your head code http-equiv do the refresh automatically after the specific seconds (43200 in our example) depends on what you want to do
Note that if you make your action start automatically without pressing submit button you can do the action in the same page.
I did that idea before, I had 180,000 images in one folder and the server didn't allow me to download it all because it was showing me only first 7998 images, so I create a script to zip each 1000 image in a file outside the images folder and to avoid time out, I made the code refresh each 60 second , finally I got only 180 zip file :)
So I am really stumped because I have basic ideas but I am looking for some of your expertise.
What I am trying to do: I want to basically write an app using Twilio which you dont really need to know about because that is another issue. What that app does is call on a php file in my web host and "triggers the php code"
What I need help with here is how can I keep record in php of the calendar of the week for my computer. What I mean by that is if someone like an admin has a specific code that I have written for them, and that code runs automatically all week, but a specific week they dont want that code to run, instead they want a different code to run that week. How can I use php to find when a week has ended or keep track of the week using that calendar in bottom right of your computer screen so that my program will know after an admin wants a different code run from the usual code that the week is over no need to run that admin irregular code any more go back to your usual automated running code.
If you still dont know what I am talking. I will try to explain more. Think of 2 separate codes. One Custom and the other automated. The automated runs all the time automatically. But one day the admin chooses for that week he doesnt want to follow the regular shcedule of running the automated code as usual, instead for that week he would like to run the custom code and after the week is over go back to running the automated code as usual.
I hope that makes it more clear. I know that in PHP gives the date. But I really need expert opinion on how to do this.
Generally for something like this, I'd generate a "nextrun_datetime" for each and every script/user combination. By default it would have a repeat interval, in your case, 7 days.
If a user doesn't want to run it this week, they can "push" it out N days and the normal update interval would apply afterwards. To get the one-time shot, I'd allow an update interval of 0 or -1 to denote that.
With this sort of thing, whenever a script is updated (or saved, run, rescheduled), you can calculate the next date if there is one. From there, it's a relatively simple cron job that should check the last N minutes for any scripts to be run.
Unless your client machines are running on a completely different calendar than the server, why bother with wondering what the client's date is? Unless the client and server are in different time zones, the client date is going to be the same as the server date, except for a few hours around midnight.
As well, why depend on the client to trigger the server-side code? If this is a regularly occuring thing, use cron or whatever's available on the server to run the code automatically. If an admin wants to override WHICH code gets run, then you can provide an interface to change what's executed. Click a button on a site and a flag is set somewhere that tells the timed job to run script B instead of script A.
I've done something similar. Based on the day (e.g. monday, sunday) I would do something different in php.
this is how I did it:
$today = date('w');
if ($today== 0){
//its sunday
exec('rmdir C:\myApp\oldLogs');
}
else{
echo '1 -> monday, 2-> tuesday etc...'
}
you can also make a date from a string for example
$date = strtotime("8 days ago 14:00");
/*
or "Monday next week", "+1 week 2 days 4 hours 2 seconds","yesterday noon","10 September 2000" etc...
*/
Say I have a game in PHP which is a money making game and everyday the prices on items change on the market.
How would I make it so the prices in the database are automatically updated each day? Would I install a program on the server that detects when it has gone 24 hours then runs a PHP file which does the updating? Or os there another way?
Edit:
The thing is guys, I don't actually own the server I rent it from a hosting company so I don't really have access the the command line :s
Thanks, Stanni
Assuming you're on a Unix system, you should setup a daily cronjob. To do this, run "crontab -e" and enter something like:
9 21 * * * /path/to/your/script
This will run at 21:09 every day.
Since you probably don't have access to cron either what I would do is check how much time has passed everytime someone loads a page. If 24 hours have passed then call your update function. If 48 hours have passed then call it twice. If no one loads the page then it doesn't matter if the update function has been called or not because no one is looking ;)
Or you could setup a computer at home to call your update.php remotely every 24 hours. You can do that with a cron job and wget or if you're using windows you could use the task scheduler.
I think the first option will work the best. Call your update function every page load and only update when the 24 hour mark has passed. If you write it correctly it doesn't matter if it gets updated at the exact 24 hour mark.
If you don't have access to the commandline, you could add a 1x1 image to the website which calls a php script which checks if there needs something be updated.
something like
<img style="width: 1px; height: 1px; visibility: hidden" src="cron.php">
In cron.php you check if the data needs to be updated.
You want to set up a "cron job", or a PHP file that runs at a certain interval you set.
Check out this article for more information.
The best part about cron jobs is that you are not limited to the small subset of functionality available in say, stored procedures. You can use whatever logic you like! :)
Use webcron :)
http://www.webcron.org/index.php?lang=en
Or here is a good list:
http://www.onlinecronservices.com/
If you have a script that updates the prices and all you want to do is run it every day, use Cron (linux) or at command (windows).
How could you not 'have access to the command line'? I can't think of any host that doesn't allow ssh access. Having access to cron is a different story, but they SHOULD allow this, also. If they don't - find a new host!
Forget all that. There is no reason to do anything like that.
All you have to do is check each time someone calls the webpage. You keep track of the date and when the current date no longer matches your variable then you fire off the thing that gets new data. Bam! Of course that's not very scalable but it's fine for a small game.
I think that you can make a function that gets called every time a page is accessed, and verifies if the update took place, checking against a database.
So in a quick pseudo code:
function verify_often(){
if (last_update_in_db() != today() ){
update_db();
run_periodic_function();
}
return 0;
}
This method requires only the classic PHP & MySQL combination.
I couldn't work out how to reply to alex's answer but I wish to mention something that they said. When they said "check how much time has passed everytime someone loads a page" I feel that you don't need to check it every time the page is loaded. The better way of doing it would be to check when a user logs in. If it goes over 24 hours while users are still logged in it will not matter for the described scenario. The next time someone logs in the prices of items will change.