How can I install from a git subdirectory with pip?

There is a pull request regarding this feature, and it seems to have been merged to develop branch a month ago. The syntax is the following:

pip install -e git+https://git.repo/some_repo.git#egg=version_subpkg&subdirectory=repo # install a python package from a repo subdirectory

We probably have to wait for a while until it gets merged to master and is distributed.

UPDATE: This is now available and documented at https://pip.pypa.io/en/stable/cli/pip_install/#vcs-support as follows:

For projects where setup.py is not in the root of project, "subdirectory" component is used. Value of "subdirectory" component should be a path starting from root of the project to where setup.py is located.

So if your repository layout is:

- pkg_dir/
  - setup.py  # setup.py for package ``pkg``
  - some_module.py
- other_dir/
  - some_file
- some_other_file

You'll need to use

pip install -e vcs+protocol://repo_url/#egg=pkg&subdirectory=pkg_dir

Note: On Windows, you must place the URL in double quotes, or you'll get an error "'subdirectory' is not recognized as an internal or external command". E.g., use:

pip install -e "vcs+protocol://repo_url#egg=pkg&subdirectory=pkg_dir"

It's been already stated in one of the comments under the correct answer, but just to highlight this issue: when executing this from Linux command line, you must escape the &-character since ampersand is telling the command line to run a command in background:

git+https://git.repo/some_repo.git#egg=version_subpkg\&subdirectory=repo

Notice the backslash before the ampersand. The escaping behaviour might depend on the Linux distro; I'm not an expert.
If you ignore this, you might run into a cryptic error like the following:

bash: (...) command not found