git: have different .gitignore file for each remote

This doesn't really make sense in git's model. Commits contain sets of files; all .gitignore files do is tell the UI not to automatically add files matching certain patterns. What this would effectively mean is to have parallel sets of commits that are almost the same, but containing only a subset of the files.

It'd be possible to do this with a branching scheme, where you have a "deployment" branch that splits off of master and is the same but contains the additional compiled files. This could even be automated with git hooks to automatically compile the files and add them to the repo. I'm envisioning a structure like this:

master:       A ---> B ---> C ---> D
               \      \      \      \
                \      \      \      \
deployment:      -> A'  -> B'  -> C'  -> D'

i.e. every time a certain server gets a new commit on master, it builds the project, adds the built files to a new commit from D, and commits that to the deployment branch -- which then doesn't have to be pushed to github.

I figured out a way to do this.

In my case, I needed to synchronize the project with heroku and GitHub (as my public repo).

But I was not interested in sharing some files with private information in a public repository.

Usually a simple project would have the following folder structure

Project folder (remote heroku)
    - .git
    - .gitignore
    - (folders and files)

What I did was add one more level, and in it create another git repository, with a .gitignore that would omit some files from my project.

Project public (remote GitHub)
    - .git
    - .gitignore
    - Project folder (remote heroku)
        - .git
        - .gitignore
        - (folders and files)

So this is not a git repository with two remote repositories with different .gitignores.

There are two different repositories.

On the innermost I only exclude the files generated by the IDE and some files generated at runtime.

At the outermost level, I exclude all files that cannot be make public.

Another option is git submodules.

This can be useful if, for instance, you want your code and documentation to be in two different repos with independent access control, etc. So you'd have 3 total repos, a submodule repo for docs, another for code, and the "master" (not a git submodule) repo containing both (for pypi upload, perhaps). This is a decent way to organize a CS textbook project. Both projects can proceed merrily ahead independently and sync up at major releases, driven by the master repo maintainer.

An automated solution to the methods mentioned here:

1. Set up the root .git to ignore the subfolder(s) you you want transmitted differently
2. Init new git within the subfolder(s) and assign the remote configuration
3. Modify the root folder's .git/hooks/pre-push file to exec git push at those sub folders based on the incoming arguments.