Virtual Environment

The use of a Virtual Environment is to test python code in encapsulated environments, and to also avoid filling the base Python installation with libraries we might use for only one project.

virtualenv

  1. Install virtualenv

    pip install virtualenv
    
  2. Install virtualenvwrapper-win (Windows)

    pip install virtualenvwrapper-win
    

Usage:

  1. Make a Virtual Environment named HelloWorld

    mkvirtualenv HelloWorld
    

    Anything we install now will be specific to this project. And available to the projects we connect to this environment.

  2. Set Project Directory

    To bind our virtualenv with our current working directory we simply enter:

    setprojectdir .
    
  3. Deactivate

    To move onto something else in the command line type deactivate to deactivate your environment.

    deactivate
    

    Notice how the parenthesis disappear.

  4. Workon

    Open up the command prompt and type workon HelloWorld to activate the environment and move into your root project folder

    workon HelloWorld
    

Poetry

From Poetry website

Poetry is a tool for dependency management and packaging in Python. It allows you to declare the libraries your project depends on and it will manage (install/update) them for you.

  1. Install Poetry

    pip install --user poetry
    
  2. Create a new project

    poetry new my-project
    

    This will create a my-project directory:

    my-project
    ├── pyproject.toml
    ├── README.rst
    ├── poetry_demo
    │   └── __init__.py
    └── tests
        ├── __init__.py
        └── test_poetry_demo.py
    

    The pyproject.toml file will orchestrate your project and its dependencies:

    [tool.poetry]
    name = "my-project"
    version = "0.1.0"
    description = ""
    authors = ["your name <your@mail.com>"]
    
    [tool.poetry.dependencies]
    python = "*"
    
    [tool.poetry.dev-dependencies]
    pytest = "^3.4"
    
  3. Packages

    To add dependencies to your project, you can specify them in the tool.poetry.dependencies section:

    [tool.poetry.dependencies]
    pendulum = "^1.4"
    

    Also, instead of modifying the pyproject.toml file by hand, you can use the add command and it will automatically find a suitable version constraint.

    $ poetry add pendulum
    

    To install the dependencies listed in the pyproject.toml:

    poetry install
    

    To remove dependencies:

    poetry remove pendulum
    

For more information, check the documentation or read here:

Pipenv

From Pipenv website

Pipenv is a tool that aims to bring the best of all packaging worlds (bundler, composer, npm, cargo, yarn, etc.) to the Python world. Windows is a first-class citizen, in our world.

  1. Install pipenv

    pip install pipenv
    
  2. Enter your Project directory and install the Packages for your project

    cd my_project
    pipenv install <package>
    

    Pipenv will install your package and create a Pipfile for you in your project’s directory. The Pipfile is used to track which dependencies your project needs in case you need to re-install them.

  3. Uninstall Packages

    pipenv uninstall <package>
    
  4. Activate the Virtual Environment associated with your Python project

    pipenv shell
    
  5. Exit the Virtual Environment

    exit
    

Find more information and a video in docs.pipenv.org.

Anaconda

Anaconda is another popular tool to manage python packages.

Where packages, notebooks, projects and environments are shared. Your place for free public conda package hosting.

Usage:

  1. Make a Virtual Environment

    conda create -n HelloWorld
    
  2. To use the Virtual Environment, activate it by:

    conda activate HelloWorld
    

    Anything installed now will be specific to the project HelloWorld

  3. Exit the Virtual Environment

    conda deactivate
    

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