====== Git: create your own git server, but sharing access to all the repositories ======


===== Intro =====

This tutorial will show how to create a remote git server but 
every user you give permissions can contribute to every 
git project in the server. 

To create a git server in which every project can see only the 
projects they have assigned, I suppose there are other solutions, 
but definitely this solution will not work, because in this 
tutorial every commit will be made by a generic git user that
can read and write in every directory. 

===== Set up a git server =====

First, install git on your machine. In my case, because it's an 
ubuntu, I've run: 

<code>
sudo apt-get install git 
</code>

===== Create git user =====

I prefer to create a "normal" **git** user instead a system one. 
If you prefer to create a system user, just add the **--system** 
option to the command:

The **--create-home** option is needed because there we will be 
storing the public keys of the users of the repository. 

<code>
useradd --create-home --user-group git
</code>

===== Enter as git user and add remote public keys =====

<code>
~$ mkdir .ssh
~$ chmod o=,g= .ssh
~$ cd .ssh
~/.ssh$ touch authorized_keys
~/.ssh$ chmod o=,g= authorized_keys
</code>

===== Add the keys of the different users of the git repository =====


<code>
~$ cat public_key_of_first_user.pub >> .ssh/authorized_keys
~$ rm public_key_of_first_user.pub # you can remove the public key afterwards if you want
</code>

===== Verification: in the first_user computer check that you can log in as git user to the remote computer =====

Check that you can make a ssh to the remote computer with no password request: 

<code>
rluna@asustao:~$ ssh git@192.168.0.21
The authenticity of host '192.168.0.21 (192.168.0.21)' can't be established.
ED25519 key fingerprint is SHA256:PvSiThCnDq8pNOXyVgsq5vsXLME6oYIbCs0v5urvcpE.
This key is not known by any other names
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '192.168.0.21' (ED25519) to the list of known hosts.

The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

git@ubuntu2004:~$ 

</code>

If this is step succeeds, you can continue. 

==== Create a directory for your repositories ====

In the server computer, I've created a ```/var/git``` directory
to hold the repositories. 

As root, do the following:

<code>
# mkdir /var/git 
# chown git:git /var/git
# chmod g=rx,o= /var/git
</code>

The permissions are set 750 to allow the git user to do 
anything inside the directory, and the group members to 
allow other users to read the contents: this will allow 
us to create other users that can read this directory
by adding them to the group of the git user. 

==== Create a repository ====

To create a repository, log in as the git user and make 
a git init --bare:

<code>
git$ cd /var/git
git$ mkdir repo1.git
git$ cd repo1.git
git$ git init --bare
</code>

Congrats! you have created your first repository. 
The .git extension of the directory is not needed, is
just to make the url of the repository more cool.