最近在使用Coding的代碼托管,順便設置了WebHook自動部署,過程還是挺艱辛的,主要還是沒搞懂Linux的權限控制,不過好在弄好了,分享一下獲益最深的一篇文章,供大家參考,原文是英文版的,我的英語也不行,勉強能看懂,大家湊合著看吧
原文鏈接:http://jondavidjohn.com/git-pull-from-a-php-script-not-so-simple/
I intended to set up a repository (hosted on BitBucket) to initiate a pull on a dev server when new commits are pushed up.
It seemed like a simple enough process. BitBucket has a service that will fire off a POST request as a post-receive hook. So I set up a receiving php script to check a randomized token and then initiate the git pull
. Looking something like this...
<?php
define('PRIVATE_KEY', 'XXXXXXXXXXXXXXXXxxx');
if ($_SERVER['REQUEST_METHOD'] === 'POST'
&& $_REQUEST['thing'] === PRIVATE_KEY)
{
echo shell_exec("git pull");
}
Didn't end up being as simple as I had anticipated...
There were a few considerations that I did not take into account. Documenting them here will hopefully help you avoid some obstacles in trying to get something like this set up.
git
in this case)The user that is attempting to execute git pull
is the apache user (www
in our case). This user did not happen to have git
in their path.
This took a while to track down because the exec()
family of functions simply fail silently because they only report STDOUT and not STDERR. To get the function to report STDERR you can route it into STDOUT by adding 2->&1
at the end of your command.
After I realized this I logged in and found the full path of the git binary with which git
, which is /full/path/to/bin/git
.
<?php
...
echo shell_exec("/full/path/to/bin/git pull 2>&1");
...
Now it was reporting the next issue...
error: cannot open .git/FETCH_HEAD: Permission denied
The apache user also needs read and write access to the entire repository.
chown -R ssh_user:www repository/
It's also a good idea to make sure any files/directories inherit this ownership if being created by others by setting the group sticky bit.
chmod -R g+s repository/
Next, you need to do an intial git pull with the apache user to make sure the remote is added to the apache user's known_hosts
file
sudo -u www git pull
Another consideration created by this command being run by the apache user is the ssh key it uses to communicate with the remote repository.
First, I went down the path of attempting to use the GIT_SSH
environment variable to set the ssh -i
option to tell it to use a specific ssh key I had generated with the ssh user. I never got this to work, most likely because there are a lot of rules ssh uses to determine the safety of a given key. It requires some specific permissions regarding the user that is attempting to use the key.
An easier way I discovered was to give the apache user a home directory (via /etc/passwd
) and a .ssh
directory and then run the ssh-keygen
command as the apache user (www
)
sudo -u www ssh-keygen -t rsa
This creates the keys and puts them in their expected location with the proper permissions applied.
Then I added the key as a read-only key for the BitBucket repository and everything worked as expected.