Advanced Usage of Pipenv

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This document covers some of Pipenv’s more glorious and advanced features.

☤ Specifying Package Indexes

If you’d like a specific package to be installed with a specific package index, you can do the following:

[[source]]
url = "https://pypi.python.org/simple"
verify_ssl = true
name = "pypi"

[[source]]
url = "http://pypi.home.kennethreitz.org/simple"
verify_ssl = false
name = "home"

[dev-packages]

[packages]
requests = {version="*", index="home"}
maya = {version="*", index="pypi"}
records = "*"

Very fancy.

☤ Specifying Basically Anything

If you’d like to specify that a specific package only be installed on certain systems, you can use PEP 508 specifiers to accomplish this.

Here’s an example Pipfile, which will only install pywinusb on Windows systems:

[[source]]
url = "https://pypi.python.org/simple"
verify_ssl = true
name = "pypi"

[packages]
requests = "*"
pywinusb = {version = "*", os_name = "== 'windows'"}

Voilà!

Here’s a more complex example:

[[source]]
url = "https://pypi.python.org/simple"
verify_ssl = true

[packages]
unittest2 = {version = ">=1.0,<3.0", markers="python_version < '2.7.9' or (python_version >= '3.0' and python_version < '3.4')"}

Magic. Pure, unadulterated magic.

☤ Deploying System Dependencies

You can tell Pipenv to install things into its parent system with the --system flag:

$ pipenv install --system

This is useful for Docker containers, and deployment infrastructure (e.g. Heroku does this).

Also useful for deployment is the --deploy flag:

$ pipenv install --system --deploy

This will fail a build if the Pipfile.lock is out–of–date, instead of generating a new one.

☤ Generating a requirements.txt

You can convert a Pipfile and Pipfile.lock into a requirements.txt file very easily, and get all the benefits of hashes, extras, and other goodies we have included.

Let’s take this Pipfile:

[[source]]
url = "https://pypi.python.org/simple"
verify_ssl = true

[packages]
requests = {version="*"}

And generate a requirements.txt out of it:

$ pipenv lock -r
chardet==3.0.4 --hash=sha256:fc323ffcaeaed0e0a02bf4d117757b98aed530d9ed4531e3e15460124c106691  --hash=sha256:84ab92ed1c4d4f16916e05906b6b75a6c0fb5db821cc65e70cbd64a3e2a5eaae
requests==2.18.4 --hash=sha256:6a1b267aa90cac58ac3a765d067950e7dbbf75b1da07e895d1f594193a40a38b  --hash=sha256:9c443e7324ba5b85070c4a818ade28bfabedf16ea10206da1132edaa6dda237e
certifi==2017.7.27.1 --hash=sha256:54a07c09c586b0e4c619f02a5e94e36619da8e2b053e20f594348c0611803704  --hash=sha256:40523d2efb60523e113b44602298f0960e900388cf3bb6043f645cf57ea9e3f5
idna==2.6 --hash=sha256:8c7309c718f94b3a625cb648ace320157ad16ff131ae0af362c9f21b80ef6ec4  --hash=sha256:2c6a5de3089009e3da7c5dde64a141dbc8551d5b7f6cf4ed7c2568d0cc520a8f
urllib3==1.22 --hash=sha256:06330f386d6e4b195fbfc736b297f58c5a892e4440e54d294d7004e3a9bbea1b  --hash=sha256:cc44da8e1145637334317feebd728bd869a35285b93cbb4cca2577da7e62db4f

Very fancy.

☤ Detection of Security Vulnerabilities

Pipenv includes the safety package, and will use it to scan your dependency graph for known security vulnerabilities!

Example:

$ cat Pipfile
[packages]
django = "==1.10.1"

$ pipenv check
Checking PEP 508 requirements…
Passed!
Checking installed package safety…

33075: django >=1.10,<1.10.3 resolved (1.10.1 installed)!
Django before 1.8.x before 1.8.16, 1.9.x before 1.9.11, and 1.10.x before 1.10.3, when settings.DEBUG is True, allow remote attackers to conduct DNS rebinding attacks by leveraging failure to validate the HTTP Host header against settings.ALLOWED_HOSTS.

33076: django >=1.10,<1.10.3 resolved (1.10.1 installed)!
Django 1.8.x before 1.8.16, 1.9.x before 1.9.11, and 1.10.x before 1.10.3 use a hardcoded password for a temporary database user created when running tests with an Oracle database, which makes it easier for remote attackers to obtain access to the database server by leveraging failure to manually specify a password in the database settings TEST dictionary.

33300: django >=1.10,<1.10.7 resolved (1.10.1 installed)!
CVE-2017-7233: Open redirect and possible XSS attack via user-supplied numeric redirect URLs
============================================================================================

Django relies on user input in some cases  (e.g.
:func:`django.contrib.auth.views.login` and :doc:`i18n </topics/i18n/index>`)
to redirect the user to an "on success" URL. The security check for these
redirects (namely ``django.utils.http.is_safe_url()``) considered some numeric
URLs (e.g. ``http:999999999``) "safe" when they shouldn't be.

Also, if a developer relies on ``is_safe_url()`` to provide safe redirect
targets and puts such a URL into a link, they could suffer from an XSS attack.

CVE-2017-7234: Open redirect vulnerability in ``django.views.static.serve()``
=============================================================================

A maliciously crafted URL to a Django site using the
:func:`~django.views.static.serve` view could redirect to any other domain. The
view no longer does any redirects as they don't provide any known, useful
functionality.

Note, however, that this view has always carried a warning that it is not
hardened for production use and should be used only as a development aid.

✨🍰✨

☤ Code Style Checking

Pipenv has Flake 8 built into it. You can check the style of your code like so, without installing anything:

$ cat t.py
import requests

$ pipenv check --style t.py
t.py:1:1: F401 'requests' imported but unused
t.py:1:16: W292 no newline at end of file

Super useful :)

☤ Open a Module in Your Editor

Pipenv allows you to open any Python module that is installed (including ones in your codebase), with the $ pipenv open command:

$ pipenv install -e git+https://github.com/kennethreitz/background.git#egg=background
Installing -e git+https://github.com/kennethreitz/background.git#egg=background…
...
Updated Pipfile.lock!

$ pipenv open background
Opening '/Users/kennethreitz/.local/share/virtualenvs/hmm-mGOawwm_/src/background/background.py' in your EDITOR.

This allows you to easily read the code you’re consuming, instead of looking it up on GitHub.

Note

The standard EDITOR environment variable is used for this. If you’re using Sublime Text, for example, you’ll want to export EDITOR=subl (once you’ve installed the command-line utility).

☤ Automatic Python Installation

If you have pyenv installed and configured, Pipenv will automatically ask you if you want to install a required version of Python if you don’t already have it available.

This is a very fancy feature, and we’re very proud of it:

$ cat Pipfile
[[source]]
url = "https://pypi.python.org/simple"
verify_ssl = true

[dev-packages]

[packages]
requests = "*"

[requires]
python_version = "3.6"

$ pipenv install
Warning: Python 3.6 was not found on your system…
Would you like us to install latest CPython 3.6 with pyenv? [Y/n]: y
Installing CPython 3.6.2 with pyenv (this may take a few minutes)…
...
Making Python installation global…
Creating a virtualenv for this project…
Using /Users/kennethreitz/.pyenv/shims/python3 to create virtualenv…
...
No package provided, installing all dependencies.
...
Installing dependencies from Pipfile.lock…
🐍   ❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒❒ 5/5 — 00:00:03
To activate this project's virtualenv, run the following:
 $ pipenv shell

Pipenv automatically honors both the python_full_version and python_version PEP 508 specifiers.

💫✨🍰✨💫

☤ Automatic Loading of .env

If a .env file is present in your project, $ pipenv shell and $ pipenv run will automatically load it, for you:

$ cat .env
HELLO=WORLD⏎

$ pipenv run python
Loading .env environment variables…
Python 2.7.13 (default, Jul 18 2017, 09:17:00)
[GCC 4.2.1 Compatible Apple LLVM 8.1.0 (clang-802.0.42)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.environ['HELLO']
'WORLD'

This is very useful for keeping production credentials out of your codebase. We do not recommend committing .env files into source control!

If your .env file is located in a different path or has a different name you may set the PIPENV_DOTENV_LOCATION environment variable:

$ PIPENV_DOTENV_LOCATION=/path/to/.env pipenv shell

☤ Configuration With Environment Variables

pipenv comes with a handful of options that can be enabled via shell environment variables. To activate them, simply create the variable in your shell and pipenv will detect it.

  • PIPENV_DEFAULT_PYTHON_VERSION — Use this version of Python when creating new virtual environments, by default (e.g. 3.6).
  • PIPENV_SHELL_FANCY — Always use fancy mode when invoking pipenv shell.
  • PIPENV_VENV_IN_PROJECT — If set, use .venv in your project directory instead of the global virtualenv manager pew.
  • PIPENV_COLORBLIND — Disable terminal colors, for some reason.
  • PIPENV_NOSPIN — Disable terminal spinner, for cleaner logs. Automatically set in CI environments.
  • PIPENV_MAX_DEPTH — Set to an integer for the maximum number of directories to resursively search for a Pipfile.
  • PIPENV_TIMEOUT — Set to an integer for the max number of seconds Pipenv will wait for virtualenv creation to complete. Defaults to 120 seconds.
  • PIPENV_IGNORE_VIRTUALENVS — Set to disable automatically using an activated virtualenv over the current project’s own virtual environment.

Also note that pip itself supports environment variables, if you need additional customization.

For example:

$ PIP_INSTALL_OPTION="-- -DCMAKE_BUILD_TYPE=Release" pipenv install -e .

☤ Custom Virtual Environment Location

Pipenv’s underlying pew dependency will automatically honor the WORKON_HOME environment variable, if you have it set — so you can tell pipenv to store your virtual environments wherever you want, e.g.:

export WORKON_HOME=~/.venvs

In addition, you can also have Pipenv stick the virtualenv in project/.venv by setting the PIPENV_VENV_IN_PROJECT environment variable.

☤ Testing Projects

Pipenv is being used in projects like Requests for declaring development dependencies and running the test suite.

We’ve currently tested deployments with both Travis-CI and tox with success.

Travis CI

An example Travis CI setup can be found in Requests. The project uses a Makefile to define common functions such as its init and tests commands. Here is a stripped down example .travis.yml:

language: python
python:
    - "2.6"
    - "2.7"
    - "3.3"
    - "3.4"
    - "3.5"
    - "3.6"
    - "3.7dev"

# command to install dependencies
install: "make"

# command to run tests
script:
    - make test

and the corresponding Makefile:

init:
    pip install pipenv
    pipenv install --dev

test:
    pipenv run py.test tests

Tox Automation Project

Alternatively, you can configure a tox.ini like the one below for both local and external testing:

[tox]
envlist = flake8-py3, py26, py27, py33, py34, py35, py36, pypy

[testenv]
passenv=HOME
deps = pipenv
commands=
    pipenv install --dev
    pipenv run py.test tests

[testenv:flake8-py3]
passenv=HOME
basepython = python3.4
commands=
    {[testenv]deps}
    pipenv install --dev
    pipenv run flake8 --version
    pipenv run flake8 setup.py docs project test

Note

With Pipenv’s default configuration, you’ll need to use tox’s passenv parameter to pass your shell’s HOME variable.

☤ Shell Completion

To enable completion in fish, add this to your config:

eval (pipenv --completion)

Magic shell completions are now enabled!

✨🍰✨

☤ Working with Platform-Provided Python Components

It’s reasonably common for platform specific Python bindings for operating system interfaces to only be available through the system package manager, and hence unavailable for installation into virtual environments with pip. In these cases, the virtual environment can be created with access to the system site-packages directory:

$ pipenv --three --site-packages

To ensure that all pip-installable components actually are installed into the virtual environment and system packages are only used for interfaces that don’t participate in Python-level dependency resolution at all, use the PIP_IGNORE_INSTALLED setting:

$ PIP_IGNORE_INSTALLED=1 pipenv install --dev