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Comment by pacemkr | Hacker News Reader

I'm dipping into both Rails and a Python project right now (non-Django), both for the first time, and had difficulty "listing required packages to go along the source" in Python.

In Rails/Ruby I can use Bundler:

  git clone
  bundle install
  [do development]

I'd like to do the same for a python project:

  git clone
  _something_ install_my_dependencies
  [do development]

I looked into pip, but it seems I have to package my src into a Python module and install that. setup.py doesn't make sense for my project since it's not a module meant for redistribution. I intend to use py2exe. Basically I just need a way to install dependencies for development.

  foreach thing in file
    pip install thing

is the best that I can come up with. This is admittedly not terrible, but I feel like there is a better way and I just don't know about it.

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There is a better way! A virtualenv combined with pip and a project requirements[1] file is the best way to handle this.

It even supports SVN/SSH checkouts and .egg distributed packages.

[1] http://www.pip-installer.org/en/latest/requirement-format.ht...

Can I use pip to just install the dependencies without packaging my project as a module? I understand that pip installs "my module" to site packages or a directory under virtualenv. This is not what I need. I don't have a "my module" to install. I just need to make sure that the dependencies are installed on the machine/virtualenv that I'm using for development.

I studied the requirement file documentation and I couldn't find a solution. It seems that to take advantage of this feature in pip I have to write a setup.py, and as I've mentioned that really doesn't make sense for my type of project. Or am I misunderstanding something?

  pip freeze > requirements.txt
  pip install -f requirements.txt

Now whenever you go to develop, pip install -f requirements.txt, when you update dependent packages, pip freeze.

You are by no means required to make your source code a module or anything like that. If you use the above with a virtualenv you can isolate different models for different projects and have them frozen at different versions. You are also able to modify requirements.txt to include version specific information. packagename==3.4.0 now locks packagename to 3.4.0 when pip goes to install it.

I'm assuming your git directory looks like this:

  $DIR
  \
  | - requirements.txt
  | - fileone.py
  | - filetwo.py
  | - folder
     \ 
      | - __init__.py
      | - filethree.py

I have several projects set up exactly like that, especially since they will never have to be distributed using a .egg or anything else.

This is exactly what I need. Thank you!

Minor correction, it's dash r:

  pip install -r requirements.txt

This is indeed correct, I must have fat fingered that. Sorry.

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