pip: Why sometimes installed as egg, sometimes installed as files

Question

Where can you force pip to install as \"flat\" and not as \"egg\".

For me it seems random. Sometimes it gets installed as egg, sometime as flat.

pip help i

Answer 1

This does not solve the question why I get sometimes zipped eggs, and sometimes not. But it helps.

You can use this in your ~/.distutils.cfg to avoid installation of zipped eggs:

[easy_install]
zip_ok = False

Answer 2

If you are the author of the package, you can use the flag zip_safe=False in setup.py.

setup(
    name = "HelloWorld",
    ...
    zip_safe = False,
)

If you are a user who wants to improve the package, you can install it by pip install -e foo_package. The option -e or --editable installs a project in editable mode (i.e. setuptools "develop mode"), not zipped. It creates a link from source into site-packages and compiles .../bin scripts, but doesn't copy the source there site-packages. Those packages can not be updated automatically and it is the main reason why it is not intended as usual way of installing packages, but only for those that need to be customized or fixed.

Edit: Django is a typical framework that requires zip_safe=False for its applications, because they are not a pure Python, but they contain also templates with html, css, i18n resources etc. Is your question related to Django?

Answer 3

I was having this egg-only install problem, and it turned out I had failed to git add the __init__.py in the root of my package. It was driving me crazy that this would work:

pip install .

...but this would fail:

mkdir /tmp/piptest
cd /tmp/piptest
git clone $OLDPWD .
pip install .

It was hard to notice the difference using diff -r . $OLDPWD because there are so many non-committed pyc files and development tool scripts.

This is probably not the answer for this OP, but I hope it helps someone who Googles "pip only installing the egg" as I did.