How to prevent checking out to an unclean remote working tree

Question

I want to setup git for a somewhat unusual use case.

I have a repository server ('repo') and I have a develop server ('develop') I want to deploy to. On the repo server I have a bare repo ('origin') which I push my changes to from my local clone.

When I push a branch called 'development' to the repo server, I have a post-receive hook there that pushes the branch to the development server:

#!/bin/bash

# post-receive on repo server

while read oldrev newrev ref
  do
  branch=`echo $ref | cut -d/ -f3`

  if [ "development" == "$branch" ]; then
    git push develop development
    echo 'Changes pushed to development server.'
  fi
done

exit 0;

On the development server I have a post-receive hook that reads

#!/bin/bash
GIT_WORK_TREE=/srv/www/htdocs/develop git checkout -f

On the develop server it might be the case that someone made changes directly in the the working tree which resides in /srv/www/htdocs/develop without using git (yeah, I know, don't ask…).

Now: What is the best way to prevent the checkout on the develop server which would destroy the non-gitters modifications?

At the moment I simulate this case using a pre-receive hook on the repo server which echoes a message and exits 1.

It would be great if I do

$ git push origin development

and git would answer like so:

Counting objects: 11, done.
Delta compression using up to 2 threads.
Compressing objects: 100% (6/6), done.
Writing objects: 100% (9/9), 706 bytes, done.
Total 9 (delta 3), reused 0 (delta 0)
remote: Unclean working directory on development server. Please fix that first.
To git@repo:development
 ! [remote rejected] development -> development (pre-receive hook declined)
error: failed to push some refs to git@repo:development'

IMHO this is not an unusual use case, but a very common one. In fact, I think it's the obvious way to deploy a web site. I actually had this working at my old job and am trying to re-find the answer I had then... It would even give a list of files that had been changed. — rjmunro, Feb 02 '12 at 18:13

score 0 · Accepted Answer · edited May 23 '17 at 12:16

I am using the "offical" post-update hook mentioned here: https://stackoverflow.com/a/3838796/3408 to prevent update the remote checkout after push.

I took some code from that to initialise the environment, and made a script to run git diff --exit-code --stat in a pre-receive hook. The --exit-code means that if there are differences, the push will be refused.

#!/bin/bash

is_bare=$(git config --get --bool core.bare)

if [ -z "$is_bare" ]
then
    # for compatibility's sake, guess
    git_dir_full=$(cd $GIT_DIR; pwd)
    case $git_dir_full in */.git) is_bare=false;; *) is_bare=true;; esac
fi

if [ "$is_bare" = "false" ]
then
    active_branch=`git symbolic-ref HEAD`
    export GIT_DIR=$(cd $GIT_DIR; pwd)
    GIT_WORK_TREE=${GIT_WORK_TREE-..}
    while read oldrev newrev ref
    do
        if [ "$ref" = "$active_branch" ]
        then
            (cd $GIT_WORK_TREE; git diff --exit-code --stat >&2)
        fi
    done
fi

I've just got this working, it's only basically tested. Others may be able to comment on if this can be simplified or improved.

How to prevent checking out to an unclean remote working tree

1 Answers1