I have a Vue application that receives updates via webhook.php - there is a little php script that updates internal configs.
At the end of this webhook.php file I have
echo shell_exec('sudo ../deploy.sh');
deploy.sh contains pretty much one line (I want to expand it a little bit later):
sudo npm run build
PHP script is doing it's work - configs are getting updated, but the build is not happening.
shell_exec() outputs nothing meaning that there is some error.
var/log/nginx/ does't show any errors.
My guess it's some problem with permissions - when I run shell_exec('sudo ../deploy.sh') from terminal, it works just like it should. But not from the webhook.php.
first try to use full path and redirect both stdout and stderr to /dev/null, then background it.
shell_exec('sudo /var/www/html/deploy.sh > /dev/null 2>&1 &');
Related
Summary: I have a command that runs on a PHP page, called by Ajax.
Latest PHP example:
$linuxCmd = "cd ~/apps && node app.js > scr_log.log 2>&1 &";
exec($linuxCmd);
I've also tried:
$linuxCmd = "cd ~/apps && node app.js > scr_log.log 2>&1";
$linuxCmd = "cd ~/apps && node app.js &";
$linuxCmd = "cd ~/apps && node app.js > /dev/null 2>&1 &";
$linuxCmd = "cd ~/apps && node app.js 2>&1 /dev/null &";
And think over the past day I've covered every possible other combination of those commands. It seems that no matter what I've tried, the ajax success function on previous page does not run. I thought that running the process above in the background would let the PHP page return back to the ajax call on the javascript page and continue running scripts, but no luck.
I've also tried adding exit() and return() after the exec() function, but it's not reaching them.
Also, the script (app.js) runs in a loop. It is terminated when a value in the database changes as it checks that every time it runs in the loop. I also have a way to kill the process, which works fine and returns to the success function of that ajax request, because it just terminates the process.
To put it another way, I need the script that I'm running from PHP exec() to constantly run after started, but also need my front end javascript page to continue after starting that process in the backend.
I'm wondering if this is maybe not possible for some reason. And if so, if there is a better way than PHP's exec() function. Also tried shell_exec with a couple of the above combinations.
Tilde expansion is a function of the shell, not something intrinsic to Linux, so your script should not rely on it working. Even if that weren't the case, web servers generally run as a separate user that doesn't have a home directory. What you should do is use absolute paths throughout your script, and don't try to write into a user directory with the web server user.
<?php
$linuxCmd = "/usr/bin/node /home/user/apps/app.js > /var/log/scr_log.log 2>&1 &";
exec($linuxCmd);
Letting your web server write to /var/log may require some permissions tweaks, but best to put things where they belong. You don't want to give something exposed to the outside – like a web server – permissions to write into a sensitive location like a home directory.
As for how best to run the command persistently in the background, see the answers to this question. There's nothing in your code that would prevent an Ajax function from returning successfully; this would only happen if the address was wrong (i.e. 404) or an error occurred (e.g. 500.)
I am using a php script on my apache/ubuntu server to call a bash script that triggers an application taking a python script as an argument (IDAPro).
PHP Code
chdir('/var/www/dashboard/team/static/sql');
$output = exec('sudo -u rohan ./start.sh');
Now, the above code works fine if I run the PHP file from the terminal - but only if I run it as the root user. Needless to say, if I execute the bash file directly it runs too.
But when I run the PHP file on the browser, it doesn't work and I get the following error in the apache error log:
QXcbConnection: Could not connect to display
Aborted
I understand that Apache/php runs as 'www-data' user (used the 'whoami' to verify), and that is why I have the sudo in my exec. I have tweaked and tinkered the permissions for both users to no avail. When I run the php file from the terminal as the 'www-data' user, it throws no error but does not do anything except display the random echo tags I at the start and end of the script to debug it.
I am a linux novice, so any help is greatly appreciated.
Okay, I finally managed to solve it.
The issue is not with the permissions, but it is with the environment variables.
I had to include the following line in my bash script
export DISPLAY=':0.0'
Note that setting the variable in the terminal and running the script does not work. The line needs to be inside the script.
I assume this is because the DISPLAY variable is not set if you run the script as any user other than root, which is what happens in case of Apache/PHP where the script is executed as the 'www-data' user.
perhaps you could use something like the following at the top of your script:
if [ "$(id -un)" != "rohan" ]; then
exec sudo -u rohan $0 "$#"
fi
export XAUTHORITY=/home/rohan/.Xauthority
export DISPLAY=:0
One of my lines of shell command is not executing despite other similar lines working. I am running on a linux machine using a Ubuntu 12.04 based OS. I have tried using exec as well, still doesn't work.
I actually had this working at some point, where I ran into the hanging issue (waiting for command output), which is why I'm redirecting output to /dev/null. So some where in the development something changed. We did create a debian package to install with and I had run that install package so I thought maybe in overwriting a file the permissions got changed so I added read/write/execute to all users/groups/owners but that didn't work either.
The code is here:
if(isset($_POST['activateXML']))
{
if (videoConsistencyCheck())
{
`cp {$fileXML} /apps/video/xml.xml`;
`sudo /apps/video/vsss restart >/dev/null 2>&1 &`;
systemUnvalidate();
header('Location: index.php?app='.$_GET['app']);
die();
}
}
I know that the first line in the if statement gets executed. The line of code works fine in the actually terminal, so that isn't the problem either. I did lots of Googling and all I could find is an unanswered question, any advice would be helpful.
EDIT: so what appeared to be not working was in fact calling the command as intended but in the bash script I was calling the start-stop daemon was not working
EDIT 2: I made a test php file and ran the code from the terminal, fixed the start-stop-daemon error by adding sudo to the commands but it still doesn't work in my code. I am calling this code when a submit button is pressed.
use additional parameters, especially output:
exec($command,$output);
var_dump($output);
to determine what can be wrong with your command. If it doesn't work, please show us your code where you use your exec's.
The issue lay with a call to a binary file in the vsss script that could only be run as root. We did not want to allow access to that binary file to just anyone. The solution we came up with involves calling chmod +s on the vsss script which allows permissions for user and group IDs but keeps its owner permissions. We then added the PHP user, which was www-data, to the sudoers file using the NOPASSWD parameter. In my PHP code I then used the line:
exec('sudo /apps/video/vsss restart >/dev/null 2>&1 &')
The shell_exec()/backticks would not work with this method.
For a website, I need to be able to start and stop a daemon process. What I am currently doing is
exec("sudo /etc/init.d/daemonToStart start");
The daemon process is started, but Apache/PHP hangs. Doing a ps aux revealed that sudo itself changed into a zombie process, effectively killing all further progress. Is this normal behavior when trying to start a daeomon from PHP?
And yes, Apache has the right to execute the /etc/init.d/daemonToStart command. I altered the /etc/sudoers file to allow it to do so. No, I have not allowed Apache to be able to execute any kind of command, just a limited few to allow the website to work.
Anyway, going back to my question, is there a way to allow PHP to start daemons in a way that no zombie process is created? I ask this because when I do the reverse, stopping an already started daemon, works just fine.
Try appending > /dev/null 2>&1 & to the command.
So this:
exec("sudo /etc/init.d/daemonToStart > /dev/null 2>&1 &");
Just in case you want to know what it does/why:
> /dev/null - redirect STDOUT to /dev/null (blackhole it, in other words)
2>&1 - redirect STDERR to STDOUT (blackhole it as well)
& detach process and run in the background
I had the same problem.
I agree with DaveRandom, you have to suppress every output (stdout and stderr). But no need to launch in another process with the ending '&': the exec() function can't check the return code anymore, and returns ok even if there is an error...
And I prefer to store outputs in a temporary file, instead of 'blackhole'it.
Working solution:
$temp = tempnam(sys_get_temp_dir(), 'php');
exec('sudo /etc/init.d/daemonToStart >'.$temp.' 2>&1');
Just read file content after, and delete temporary file:
$output = explode("\n", file_get_contents($temp));
#unlink($temp);
I have never tried starting a daemon from PHP, but I have tried running other shell commands, with much trouble. Here are a few things I have tried, in the past:
As per DaveRandom's answer, append /dev/null 2>&1 & to the end of your command. This will redirect errors to standard output. You can then use this output to debug.
Make sure your webserver's user's PATH contains all referenced binaries inside your daemon script. You can do this by calling exec('echo $PATH; whoami;). This will tell you the user PHP is running under, and it's current PATH variable.
I'm writing a class who let me access to recutils through PHP.
I have a 'database' file called books.rec in ../database/ and a script who runs my Recutils.php class.
My class simply launch system application with correct parameters.
But When I try to use recins with PHP's exec function, the command doesn't work will it work in command line.
This is the command that is executed by my script :
recins -f Title -v "Moi" -f Author -v "Moche" -f Location -v "loaned" -t Books ../database/books.rec
With PHP : Nothing, the record is not inserted (no error message at all too).
In terminal : OK, the command is well done and my record is inserted.
I also have a method to do a select operation using recsel and it works very well, will it use exactly the same file (and runs from exec too).
So, could someone explain me why the command don't work will another with the same file work ?
Thanks
PS : Further informations : http://www.gnu.org/software/recutils/
I would double check that you are running the command as the same user from the command line and your php script. That may be the problem. exec('whoami')
You said you had a script that starts your php script it should be the same user as that.
You might also want to running a simpler exec command to see if that will work first.
Other things to try:
Try checking stderr output exec('ls /tmp 2>&1', $out); This will redirect standard error to standard out so you get both.
Try using php's shell_exec() which will invoke a shell just like when you are running from the command line(eg. bash). shell_exec('ls /tmp 2>&1 >> /tmp/log') should even put all output into a log file.
I don't think this will help you but it is something to try if all else fails, set it as a background process and see if it completes. exec('nohup php process.php > process.out 2> process.err < /dev/null &'). The & will set the command to run in the background and let the script continue.
Good Luck
Is recins command accessible for PHP ? Also is path to books.rec correct ?
Try with absolute path.