Buildpack: Python

This is the official Scalingo buildpack for Python apps, powered by Pipenv, pip and other excellent software.

Recommended web frameworks include Django and Flask, among others. The recommended webserver is Gunicorn. There are no restrictions around what software can be used (as long as it's pip-installable). Web processes must bind to $PORT, and only the HTTP protocol is permitted for incoming connections.

Python packages with C dependencies that are not available on the base image are generally not supported, unless manylinux wheels are provided by the package maintainers (common).

See it in Action with pip

$ ls
my-application		requirements.txt	runtime.txt

$ git push scalingo master
Counting objects: 4, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (4/4), 276 bytes | 276.00 KiB/s, done.
Total 4 (delta 0), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote:
remote: -----> Python app detected
remote: -----> Installing python-3.7.4
remote: -----> Installing pip
remote: -----> Installing SQLite3
remote: -----> Installing requirements with pip
remote:        Collecting flask (from -r /tmp/build_c2c067ef79ff14c9bf1aed6796f9ed1f/requirements.txt (line 1))
remote:          Downloading ...
remote:        Installing collected packages: Werkzeug, click, MarkupSafe, Jinja2, itsdangerous, flask
remote:        Successfully installed Jinja2-2.10 MarkupSafe-1.1.0 Werkzeug-0.14.1 click-7.0 flask-1.0.2 itsdangerous-1.1.0
remote:
remote: -----> Discovering process types
remote:        Procfile declares types -> (none)
remote:

A requirements.txt must be present at the root of your application's repository to deploy.

See it in Action with Pipenv

Deploying a Python application couldn't be easier:

$ ls
Pipfile		Pipfile.lock	Procfile	web.py

$ scalingo create my-python-app

$ git push scalingo master
…
-----> Python app detected
-----> Installing python-3.6.9
-----> Installing pip
-----> Installing requirements with Pipenv 2018.5.18…
       ...
       Installing dependencies from Pipfile…
-----> Discovering process types
       Procfile declares types -> (none)

A Pipfile and a Pipfile.lock must be present at the root of your application's repository.

Current default Python Runtime: Python 3.6.7

Specify a Buildpack Version

You can specify the latest production release of this buildpack for upcoming builds of an existing application:

$ scalingo env-set BUILDPACK_URL=https://github.com/Scalingo/python-buildpack

Specify a Python Runtime

Supported runtime options include:

python-3.8.2
python-3.7.6
python-3.6.10
python-2.7.17

Tests

The buildpack tests use Docker to simulate Heroku's stack images.

To run the test suite:

make test

Or to test in a particular stack:

make test-heroku-18
make test-heroku-16