pip freeze does not show all installed packages

Question

I am using a virtualenv. I have fabric installed, with pip. But a pip freeze does not give any hint about that. The package is there, in my virtualenv, but pip is silent about it. Why could that be? Any way to debug this?

Answer 1

I just tried this myself:

create a virtualenv in to the "env" directory:

$virtualenv2.7 --distribute env
New python executable in env/bin/python
Installing distribute....done.
Installing pip................done.

next, activate the virtual environment:

$source env/bin/activate

the prompt changed. now install fabric:

(env)$pip install fabric
Downloading/unpacking fabric
  Downloading Fabric-1.6.1.tar.gz (216Kb): 216Kb downloaded
  Running setup.py egg_info for package fabric   
...

Successfully installed fabric paramiko pycrypto
Cleaning up...

And pip freeze shows the correct result:

(env)$pip freeze
Fabric==1.6.1
distribute==0.6.27
paramiko==1.10.1
pycrypto==2.6
wsgiref==0.1.2

Maybe you forgot to activate the virtual environment? On a *nix console type which pip to find out.

Answer 2

You can try using the --all flag, like this:

pip freeze --all > requirements.txt