How can I get a list of locally installed Python modules?
Solution
Do not use with pip > 10.0!
My 50 cents for getting a pip freeze
-like list from a Python script:
import pip
installed_packages = pip.get_installed_distributions()
installed_packages_list = sorted(["%s==%s" % (i.key, i.version)
for i in installed_packages])
print(installed_packages_list)
As a (too long) one liner:
sorted(["%s==%s" % (i.key, i.version) for i in pip.get_installed_distributions()])
Giving:
['behave==1.2.4', 'enum34==1.0', 'flask==0.10.1', 'itsdangerous==0.24',
'jinja2==2.7.2', 'jsonschema==2.3.0', 'markupsafe==0.23', 'nose==1.3.3',
'parse-type==0.3.4', 'parse==1.6.4', 'prettytable==0.7.2', 'requests==2.3.0',
'six==1.6.1', 'vioozer-metadata==0.1', 'vioozer-users-server==0.1',
'werkzeug==0.9.4']
Scope
This solution applies to the system scope or to a virtual environment scope, and covers packages installed by setuptools
, pip
and (god forbid) easy_install
.
My use case
I added the result of this call to my flask server, so when I call it with http://example.com/exampleServer/environment
I get the list of packages installed on the server's virtualenv. It makes debugging a whole lot easier.
Caveats
I have noticed a strange behaviour of this technique - when the Python interpreter is invoked in the same directory as a setup.py
file, it does not list the package installed by setup.py
.
Steps to reproduce:
Create a virtual environment$ cd /tmp
$ virtualenv test_env
New python executable in test_env/bin/python
Installing setuptools, pip...done.
$ source test_env/bin/activate
(test_env) $
Clone a git repo with setup.py
(test_env) $ git clone https://github.com/behave/behave.git
Cloning into 'behave'...
remote: Reusing existing pack: 4350, done.
remote: Total 4350 (delta 0), reused 0 (delta 0)
Receiving objects: 100% (4350/4350), 1.85 MiB | 418.00 KiB/s, done.
Resolving deltas: 100% (2388/2388), done.
Checking connectivity... done.
We have behave's setup.py
in /tmp/behave
:
(test_env) $ ls /tmp/behave/setup.py
/tmp/behave/setup.py
Install the python package from the git repo
(test_env) $ cd /tmp/behave && pip install .
running install
...
Installed /private/tmp/test_env/lib/python2.7/site-packages/enum34-1.0-py2.7.egg
Finished processing dependencies for behave==1.2.5a1
If we run the aforementioned solution from /tmp
>>> import pip
>>> sorted(["%s==%s" % (i.key, i.version) for i in pip.get_installed_distributions()])
['behave==1.2.5a1', 'enum34==1.0', 'parse-type==0.3.4', 'parse==1.6.4', 'six==1.6.1']
>>> import os
>>> os.getcwd()
'/private/tmp'
If we run the aforementioned solution from /tmp/behave
>>> import pip
>>> sorted(["%s==%s" % (i.key, i.version) for i in pip.get_installed_distributions()])
['enum34==1.0', 'parse-type==0.3.4', 'parse==1.6.4', 'six==1.6.1']
>>> import os
>>> os.getcwd()
'/private/tmp/behave'
behave==1.2.5a1
is missing from the second example, because the working directory contains behave
's setup.py
file.
I could not find any reference to this issue in the documentation. Perhaps I shall open a bug for it.
help('modules')
in a Python shell/prompt.