Pipenv - Melbourne Python User Group (MPUG)

August 2018 presentation introducing the Pipenv dependency management tool.

Transcript

1. pipenv The Future of Python Dependency Management
2. Rory Hart Biarri Rail Railroad Planning & Scheduling Software CTO - Biarri Rail @falican
3. Hiring Senior Fullstack Python + Javascript
4. Acknowledgement This talk liberally borrows from Kenneth Reitz’s PyCon talk of the same name. Follow @kennethreitz - creator of Requests: HTTP for Humans
5. The Current State of Things
6. A lot of tooling for newbies • pip • requirements.txt • requirements_dev.txt • requirements_*.txt • virtualenv • + virtualenvwrapper • pyenv • + pyenv-virtualenv • + a bunch more plugins … • anaconda
7. This tooling has a missing feature Management of “transitive dependencies”. A B C A C
8. Why do we need this? $ pip install requests Collecting requests Collecting urllib3<1.24,>=1.21.1 (from requests) Collecting certifi>=2017.4.17 (from requests) Collecting idna<2.8,>=2.5 (from requests) Collecting chardet<3.1.0,>=3.0.2 (from requests) Installing collected packages: urllib3, certifi, idna, chardet, requests Successfully installed certifi-2018.4.16 chardet-3.0.4 idna-2.6 requests-2.19.1 urllib3-1.23 $ pip install requests Collecting requests Collecting urllib3<1.24,>=1.21.1 (from requests) Collecting certifi>=2017.4.17 (from requests) Collecting idna<2.8,>=2.5 (from requests) Collecting chardet<3.1.0,>=3.0.2 (from requests) Installing collected packages: urllib3, certifi, idna, chardet, requests Successfully installed certifi-2018.4.16 chardet-3.0.4 idna-2.7 requests-2.19.1 urllib3-1.23
9. But pip has this feature right? Sort of . . . $ pip freeze > requirements.txt $ cat requirements.txt certifi==2018.4.16 chardet==3.0.4 idna==2.7 requests==2.19.1 urllib3==1.23 But this mixes “what I want installed” with ”what I need installed”.
10. So we have two problems in Python 1. Managing application dependencies is complex for newbies. 2. Dependency management could be better.
11. A solution is at hand
12. What do other languages do? Nodejs: yarn & npm (lockfile) PHP: Composer (lockfile) Rust: Cargo (lockfile) Ruby: Bundler (lockfile)
13. $ cat Pipfile [[source]] url = "https://pypi.org/simple" verify_ssl = true name = "pypi" [packages] requests = "*” [dev-packages] [requires] python_version = "3.6" A new standard that will eventually be supported by pip. https://github.com/pypa/pipfile Pipfile
14. Pipfile.lock
16. Already usable with pipenv Officially recommended tool on python.org. Automates virtualenv. Simplifies different python versions (with pyenv). Ensures deterministic builds!
17. Demo Time!
18. Questions?