Re: Newbie grief

From: Michael Witten <mfwitten@gmail.com>
Date: May 1, 2012, 05:32 UTC
Message-ID: <08704bd2e32343a4b9def80e4fa1efa2-mfwitten@gmail.com>
In-Reply-To: <4F9F52B9.9060508@palm.com>

On Mon, 30 Apr 2012 20:04:25 -0700, Rich Pixley wrote:

> I don't need separate branches for each repository.  What I really want 
> is a common branch whose changes I can push back and forth between the 
> various repositories, or coordinate through a central cache, without 
> worrying about the underlying details that git is forcing me to confront.

Here's a start for a more precise discussion.

Sincerely, Michael Witten

Cache server:

  $ git clone --mirror "$uri_for_central_repo"

Machine A:

  $ git clone "$uri_for_cache_repo"
  $ git checkout -b feature_0 origin/feature_0
  $ # ... do some work ...
  $ git push --set-upstream origin HEAD:shared/feature_0
  $ git config push.default upstream

Machine B:

  $ git clone "$uri_for_cache_repo"
  $ git checkout -b feature_0 origin/feature_0
  $ # ... do some work that conflicts with work done on Machine A...
  $ git push --set-upstream origin HEAD:shared/feature_0
  To $uri_for_cache_repo
   ! [rejected]        HEAD -> shared/feature_0 (non-fast-forward)
   error: failed to push some refs to '$uri_for_cache_repo'
  To prevent you from losing history, non-fast-forward updates were rejected
  Merge the remote changes (e.g. 'git pull') before pushing again.  See the
  'Note about fast-forwards' section of 'git push --help' for details.
  $ git pull origin shared/feature_0
  From $uri_for_cache_repo
   * branch            shared/feature_0 -> FETCH_HEAD
  Auto-merging a
  CONFLICT (add/add): Merge conflict in a
  Recorded preimage for 'a'
  Automatic merge failed; fix conflicts and then commit the result.
  $ # ... resolve conflict and commit results ...
  $ git push --set-upstream origin HEAD:shared/feature_0
  $ git config push.default upstream

Machine A:

  $ git pull # pulls in origin's shared/feature_0
  $ # ... do some work ...
  $ git push # pushes to origin's shared/feature_0

Machine B:

  $ git pull # pulls in origin's shared/feature_0
  $ # ... do some work ...
  $ git push # pushes to origin's shared/feature_0

Machine A:

  $ git pull
  $ git remote add central "$uri_for_central_repo"
  $ git push central HEAD:feature_0 # Assume there is a conflict
  To $uri_for_central_repo
   ! [rejected]        HEAD -> feature_0 (non-fast-forward)
  error: failed to push some refs to '$uri_for_central_repo'
  To prevent you from losing history, non-fast-forward updates were rejected
  Merge the remote changes (e.g. 'git pull') before pushing again.  See the
  'Note about fast-forwards' section of 'git push --help' for details.
  $ git pull central feature_0
  $ # ... resolve conflict and commit results ...
  $ git push central HEAD:feature_0 # Assume it succeeds this time
  $ # Let's update the cache repo from Machine A:
  $ git fetch central
  $ git push origin 'refs/remotes/central/*:refs/heads/*'

Machine B:

  $ git pull
  $ git pull . origin/feature_0 # Get new stuff cached from central server