Python Virtual Environment.md

Python Virtual Environment

Python venv (virtural environment) comes package with Python 3.

Setting up venv

1. Execute the following command to create a virtual environment

   Mac

   # Creates venv folder in the current directory
   $ python -m venv venv

   Windows

   REM Creates venv folder in the current directory
   > py -3 -m venv venv

Running venv

1. Startup your virtual environment:

   Mac

   # Makes venv the default Python interpreter
   $ . venv/bin/activate
   
   # OR
   
   $ source venv/bin/activate 

   Windows

   REM Makes venv the default Python interpreter
   $ .\venv\Scripts\activate.bat

2. Shutting down virtual environment

   Mac

   # Turns of venv
   $ deactivate

   Windows

   REM Turns of venv
   $ .\venv\Scripts\deactivate.bat

Running Flask application

1. Install python dependencies

   While venv is activated execute the following command

   Mac

   # Install all application libraries
   $ pip install -r requirements.txt

   Windows

   REM Install all application libraries
   > pip install -r requirements.txt

2. Start flask application

   Mac

   $ venv/bin/flask run --no-debugger
   

   Windows

   your .flaskenv file will have to look like

       FLASK_APP=app.py 
       FLASK_ENV=development