Unleash the Python Kraken Pyenv and Poetry - The Holy Grail of Python Project Setups

Abstract

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Get the gears ready

• pyenv & poetry Installation

Use pyenv to manage

• Python Interpreter Version
• Python Virtualenv

Use poetry to manage

• Python Dependencies

pyenv & poetry Installation

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pyenv

# Installation Script
#!/bin/bash
brew install pyenv
brew install pyenv-virtualenv
 
echo '
eval "$(pyenv init --path)"
eval "$(pyenv init -)"
eval "$(pyenv virtualenv-init -)"
' >> $HOME/.zshrc
zsh

poetry

# Install Poetry
 
# Using pip
pip3 install poetry
 
# Or using pipx
pipx install poetry

Python Interpreter Version

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Manage multiple Python versions in a single OS with ease

• Sometimes, we have multiple python projects on one single machine
• Some python project requires certain python version like Python3.8, but you only have Python3.10
• It is a mess to manage multiple python versions on a single machine natively

Command Cheatsheet

# List python versions installed
pyenv versions
 
# Install Python 3.10.4
pyenv install 3.10.4
 
# Select Python 3.10.4 to be used locally/globally
pyenv local 3.10.4
pyenv global 3.10.4
 
# Remove Python 3.10.4
pyenv uninstall 3.10.4

Python Virtualenv

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Create, access and manage virtualenv with ease

• It can be hard to assign different python version to different python projects virtualenv
• Each env configuration folder is inside that project folder, we must specify the Pathname to active
• It is also hard to have a quick overview of all the virtualenvs we have on a system

Command Cheatsheet

# List all the virtualenvs managed by pyenv
pyenv virtualenvs
 
# Create a new virtualenv called datadog_learn with Python 3.10.4
pyenv virtualenv 3.10.4 datadog_learn
 
# Enter a virtualenv called datadog_learn
pyenv activate datadog_learn
 
# Exit current virtualenv
pyenv deactivate 
 
# Remove a virtualenv called datadog_learn without confirmation
pyenv uninstall datadog_learn -f

Python Dependencies

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Install the correct dependency versions for a project, and enforce it!

• When you install a dependency, this dependency may depend on other dependencies which will also be installed, then you dont really know what exact dependency you are interacting directly
• We are unable to enforce the python version used natively - which may lead to failed build, because some dependencies don’t support that particular python version used on the local machine

Command Cheatsheet

# List the current poetry dev env
poetry env info
 
# List all the dependencies (including dev) installed
poetry show
 
# Install poetry in the project if it isn't initialised
poetry init
 
# Install all the dependencies
poetry install
 
# Add ddtrace as a dev dependency, remove --dev to add as a normal dependency
poetry add ddtrace --dev