Difference Between 'Python Setup.Py Install' and 'Pip Install'

Difference between 'python setup.py install' and 'pip install'

On the surface, both do the same thing: doing either python setup.py install or pip install <PACKAGE-NAME> will install your python package for you, with a minimum amount of fuss.

However, using pip offers some additional advantages that make it much nicer to use.

• pip will automatically download all dependencies for a package for you. In contrast, if you use setup.py, you often have to manually search out and download dependencies, which is tedious and can become frustrating.
• pip keeps track of various metadata that lets you easily uninstall and update packages with a single command: pip uninstall <PACKAGE-NAME> and pip install --upgrade <PACKAGE-NAME>. In contrast, if you install a package using setup.py, you have to manually delete and maintain a package by hand if you want to get rid of it, which could be potentially error-prone.
• You no longer have to manually download your files. If you use setup.py, you have to visit the library's website, figure out where to download it, extract the file, run setup.py... In contrast, pip will automatically search the Python Package Index (PyPi) to see if the package exists there, and will automatically download, extract, and install the package for you. With a few exceptions, almost every single genuinely useful Python library can be found on PyPi.
• pip will let you easily install wheels, which is the new standard of Python distribution. More info about wheels.
• pip offers additional benefits that integrate well with using virtualenv, which is a program that lets you run multiple projects that require conflicting libraries and Python versions on your computer. More info.
• pip is bundled by default with Python as of Python 2.7.9 on the Python 2.x series, and as of Python 3.4.0 on the Python 3.x series, making it even easier to use.

So basically, use pip. It only offers improvements over using python setup.py install.

---

If you're using an older version of Python, can't upgrade, and don't have pip installed, you can find more information about installing pip at the following links:

• Official instructions on installing pip for all operating systems
• Instructions on installing pip on Windows (including solutions to common problems)
• Instructions on installing pip for Mac OX

pip, by itself, doesn't really require a tutorial. 90% of the time, the only command you really need is pip install <PACKAGE-NAME>. That said, if you're interested in learning more about the details of what exactly you can do with pip, see:

• Quickstart guide
• Official documentation.

It is also commonly recommended that you use pip and virtualenv together. If you're a beginner to Python, I personally think it'd be fine to start of with just using pip and install packages globally, but eventually I do think you should transition to using virtualenv as you tackle more serious projects.

If you'd like to learn more about using pip and virtualenv together, see:

• Why you should be using pip and virtualenv
• A non-magical introduction to Pip and Virtualenv for Python beginners
• Virtual Environments

Difference between pip3 and `python3 setup.py install` regarding cmdclass argument

pip calls your setup.py but it redirects stdout/stderr. To test setup.py under pip write to a file in a fixed location:

class ActionOnInstall(install):
    def run(self):
        print("Call install.run(self) works!", file=open('/tmp/debug.log', 'w'))
        install.run(self)

Look into /tmp/debug.log after pip install .

What's the difference between pip install and python -m pip install?

They do exactly the same thing. In fact, the docs for distributing Python modules were just updated to suggest using python -m pip instead of the pip executable, because it's easier to tell which version of python is going to be used to actually run pip that way.

---

Here's some more concrete "proof", beyond just trusting my word and the bug report I linked :)

If you take a look at the pip executable script, it's just doing this:

from pkg_resources import load_entry_point
<snip>
load_entry_point('pip==1.5.4', 'console_scripts', 'pip')()

It's calling load_entry_point, which returns a function, and then executing that function. The entry point it's using is called 'console_scripts'. If you look at the entry_points.txt file for pip (/usr/lib/python2.7/dist-packages/pip-1.5.4.egg-info/entry_points.txt on my Ubuntu machine), you'll see this:

[console_scripts]
pip = pip:main
pip2.7 = pip:main
pip2 = pip:main

So the entry point returned is the main function in the pip module.

When you run python -m pip, you're executing the __main__.py script inside the pip package. That looks like this:

import sys
from .runner import run

if __name__ == '__main__':
    exit = run()
    if exit:
        sys.exit(exit)

And the runner.run function looks like this:

def run():
    base = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
    ## FIXME: this is kind of crude; if we could create a fake pip
    ## module, then exec into it and update pip.__path__ properly, we
    ## wouldn't have to update sys.path:
    sys.path.insert(0, base)
    import pip
    return pip.main()

As you can see, it's just calling the pip.main function, too. So both commands end up calling the same main function in pip/__init__.py.

pip install --editable ./ vs python setup.py develop

Try to avoid calling setup.py directly, it will not properly tell pip that you've installed your package.

With pip install -e:

For local projects, the “SomeProject.egg-info” directory is created
relative to the project path. This is one advantage over just using
setup.py develop, which creates the “egg-info” directly relative the
current working directory.

More: docs

Also read the setuptools' docs.

Difference between setup.py install and setup.py develop

develop creates an .egg-link file in the site-packages directory, which points back to the location of the project files. The same path is also added to the easy-install.pth file in the same location. Uninstalling with setup.py develop -u removes that link file again.

Do note that any install_requires dependencies not yet present are also installed, as regular eggs (they are easy_install-ed). Those dependencies are not uninstalled when uninstalling the development egg.

---

Related Topics