Sometimes I download the python source code from github and don't know how to install all the dependencies. If there is no requirements.txt file I have to create it by hands.
The question is:
Given the python source code directory is it possible to create requirements.txt automatically from the import section?
You can use the following code to generate a requirements.txt file:
pip install pipreqs
pipreqs /path/to/project
more info related to pipreqs can be found here.
Sometimes you come across pip freeze, but this saves all packages in the environment including those that you don't use in your current project.
In my case, I use Anaconda, so running the following command from conda terminal inside my environment solved it, and created this requirements txt file for me automatically:
conda list -e > requirements.txt
This was taken from this Github link pratos/condaenv.txt
Make sure to run pip3 for python3.7.
pip3 freeze >> yourfile.txt
Before executing the above command make sure you have created a virtual environment.
python3:
pip3 install virtualenv
python3 -m venv <myenvname>
python2:
pip install virtualenv
virtualenv <myenvname>
After that put your source code in the directory. If you run the python file now, probably It won't launch If you are using non-native modules. You can install those modules runing
pip3 install <module> or pip install <module>
This will not affect you entire module list except the environment you are In.
Now you can execute the command at the top and now you have a requirements file which contains only the modules you installed in the virtual environment. Now you can run the command at the top.
I advise everyone to use environments as It makes things easier when It comes to stuff like this.
Hope this helped.
来源：https://stackoverflow.com/questions/31684375/automatically-create-requirements-txt