python-dotenv 0.13.0

Add .env support to your django/flask apps in development and deployments

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python-dotenv |

Reads the key-value pair from .env file and adds them to environment variable. It is great for managing app settings during development and in production using 12-factor principles.

Do one thing, do it well!

Usages

The easiest and most common usage consists on calling load_dotenv when the application starts, which will load environment variables from a file named .env in the current directory or any of its parents or from the path specificied; after that, you can just call the environment-related method you need as provided by os.getenv.

.env looks like this:

# a comment that will be ignored.
REDIS_ADDRESS=localhost:6379
MEANING_OF_LIFE=42
MULTILINE_VAR="hello\nworld"

You can optionally prefix each line with the word export, which is totally ignored by this library, but might allow you to source the file in bash.

export S3_BUCKET=YOURS3BUCKET
export SECRET_KEY=YOURSECRETKEYGOESHERE

Python-dotenv can interpolate variables using POSIX variable expansion.

The value of a variable is the first of the values defined in the following list:

• Value of that variable in the environment.
• Value of that variable in the .env file.
• Default value, if provided.
• Empty string.

Ensure that variables are surrounded with {} like ${HOME} as bare variables such as $HOME are not expanded.

CONFIG_PATH=${HOME}/.config/foo
DOMAIN=example.org
EMAIL=admin@${DOMAIN}
DEBUG=${DEBUG:-false}

Getting started

Install the latest version with:

pip install -U python-dotenv

Assuming you have created the .env file along-side your settings module.

.
├── .env
└── settings.py

Add the following code to your settings.py:

# settings.py
from dotenv import load_dotenv
load_dotenv()

# OR, the same with increased verbosity
load_dotenv(verbose=True)

# OR, explicitly providing path to '.env'
from pathlib import Path  # python3 only
env_path = Path('.') / '.env'
load_dotenv(dotenv_path=env_path)

At this point, parsed key/value from the .env file is now present as system environment variable and they can be conveniently accessed via os.getenv():

# settings.py
import os
SECRET_KEY = os.getenv("EMAIL")
DATABASE_PASSWORD = os.getenv("DATABASE_PASSWORD")

load_dotenv does not override existing System environment variables. To override, pass override=True to load_dotenv().

load_dotenv also accepts encoding parameter to open the .env file. The default encoding is platform dependent (whatever locale.getpreferredencoding() returns), but any encoding supported by Python can be used. See the codecs module for the list of supported encodings.

You can use find_dotenv() method that will try to find a .env file by (a) guessing where to start using __file__ or the working directory -- allowing this to work in non-file contexts such as IPython notebooks and the REPL, and then (b) walking up the directory tree looking for the specified file -- called .env by default.

from dotenv import load_dotenv, find_dotenv
load_dotenv(find_dotenv())

In-memory filelikes

It is possible to not rely on the filesystem to parse filelikes from other sources (e.g. from a network storage). load_dotenv and dotenv_values accepts a filelike stream. Just be sure to rewind it before passing.

>>> from io import StringIO     # Python2: from StringIO import StringIO
>>> from dotenv import dotenv_values
>>> filelike = StringIO('SPAM=EGGS\n')
>>> filelike.seek(0)
>>> parsed = dotenv_values(stream=filelike)
>>> parsed['SPAM']
'EGGS'

The returned value is dictionary with key-value pairs.

dotenv_values could be useful if you need to consume the envfile but not apply it directly into the system environment.

Django

If you are using Django, you should add the above loader script at the top of wsgi.py and manage.py.

IPython Support

You can use dotenv with IPython. You can either let the dotenv search for .env with %dotenv or provide the path to the .env file explicitly; see below for usages.

%load_ext dotenv

# Use find_dotenv to locate the file
%dotenv

# Specify a particular file
%dotenv relative/or/absolute/path/to/.env

# Use '-o' to indicate override of existing variables
%dotenv -o

# Use '-v' to turn verbose mode on
%dotenv -v

Command-line Interface

For command-line support, use the CLI option during installation:

pip install -U "python-dotenv[cli]"

A CLI interface dotenv is also included, which helps you manipulate the .env file without manually opening it. The same CLI installed on remote machine combined with fabric (discussed later) will enable you to update your settings on a remote server; handy, isn't it!

Usage: dotenv [OPTIONS] COMMAND [ARGS]...

  This script is used to set, get or unset values from a .env file.

Options:
  -f, --file PATH                 Location of the .env file, defaults to .env
                                  file in current working directory.
  -q, --quote [always|never|auto]
                                  Whether to quote or not the variable values.
                                  Default mode is always. This does not affect
                                  parsing.
  --help                          Show this message and exit.

Commands:
  get    Retrive the value for the given key.
  list   Display all the stored key/value.
  run    Run command with environment variables from .env file present
  set    Store the given key/value.
  unset  Removes the given key.

Setting config on Remote Servers

We make use of excellent Fabric to accomplish this. Add a config task to your local fabfile; dotenv_path is the location of the absolute path of .env file on the remote server.

# fabfile.py

import dotenv
from fabric.api import task, run, env

# absolute path to the location of .env on remote server.
env.dotenv_path = '/opt/myapp/.env'

@task
def config(action=None, key=None, value=None):
    '''Manage project configuration via .env

    e.g: fab config:set,<key>,<value>
         fab config:get,<key>
         fab config:unset,<key>
         fab config:list
    '''
    run('touch %(dotenv_path)s' % env)
    command = dotenv.get_cli_string(env.dotenv_path, action, key, value)
    run(command)

Usage is designed to mirror the Heroku config API very closely.

Get all your remote config info with fab config:

$ fab config
foo="bar"

Set remote config variables with fab config:set,<key>,<value>:

$ fab config:set,hello,world

Get a single remote config variables with fab config:get,<key>:

$ fab config:get,hello

Delete a remote config variables with fab config:unset,<key>:

$ fab config:unset,hello

Thanks entirely to fabric and not one bit to this project, you can chain commands like so: fab config:set,<key1>,<value1> config:set,<key2>,<value2>

$ fab config:set,hello,world config:set,foo,bar config:set,fizz=buzz

Related Projects

• Honcho - For managing Procfile-based applications.
• django-dotenv
• django-environ
• django-configuration
• dump-env
• environs
• dynaconf

Acknowledgements

This project is currently maintained by Saurabh Kumar and Bertrand Bonnefoy-Claudet and would not have been possible without the support of these awesome people.

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

Unreleased

No unreleased change at this time.

0.13.0 - 2020-04-16

Added

• Add support for a Bash-like default value in variable expansion (#248 by @bbc2).

0.12.0 - 2020-02-28

Changed

• Use current working directory to find .env when bundled by PyInstaller (#213 by @gergelyk).

Fixed

• Fix escaping of quoted values written by set_key (#236 by @bbc2).
• Fix dotenv run crashing on environment variables without values (#237 by @yannham).
• Remove warning when last line is empty (#238 by @bbc2).

0.11.0 - 2020-02-07

Added

• Add interpolate argument to load_dotenv and dotenv_values to disable interpolation (#232 by @ulyssessouza).

Changed

• Use logging instead of warnings (#231 by @bbc2).

Fixed

• Fix installation in non-UTF-8 environments (#225 by @altendky).
• Fix PyPI classifiers (#228 by @bbc2).

0.10.5 - 2020-01-19

Fixed

• Fix handling of malformed lines and lines without a value (#222 by @bbc2):
  • Don't print warning when key has no value.
  • Reject more malformed lines (e.g. "A: B", "a='b',c").
• Fix handling of lines with just a comment (#224 by @bbc2).

0.10.4 - 2020-01-17

Added

• Make typing optional (#179 by @techalchemy).
• Print a warning on malformed line (#211 by @bbc2).
• Support keys without a value (#220 by @ulyssessouza).

0.10.3

• Improve interactive mode detection (@andrewsmith)(#183).
• Refactor parser to fix parsing inconsistencies (@bbc2)(#170).
  • Interpret escapes as control characters only in double-quoted strings.
  • Interpret # as start of comment only if preceded by whitespace.

0.10.2

• Add type hints and expose them to users (@qnighy)(#172)
• load_dotenv and dotenv_values now accept an encoding parameter, defaults to None (@theskumar)(@earlbread)([#161])
• Fix str/unicode inconsistency in Python 2: values are always str now. (@bbc2)(#121)
• Fix Unicode error in Python 2, introduced in 0.10.0. (@bbc2)(#176)

0.10.1

• Fix parsing of variable without a value (@asyncee)(@bbc2)(#158)

0.10.0

• Add support for UTF-8 in unquoted values (@bbc2)(#148)
• Add support for trailing comments (@bbc2)(#148)
• Add backslashes support in values (@bbc2)(#148)
• Add support for newlines in values (@bbc2)(#148)
• Force environment variables to str with Python2 on Windows (@greyli)
• Drop Python 3.3 support (@greyli)
• Fix stderr/-out/-in redirection (@venthur)

0.9.0

• Add --version parameter to cli (@venthur)
• Enable loading from current directory (@cjauvin)
• Add 'dotenv run' command for calling arbitrary shell script with .env (@venthur)

0.8.1

• Add tests for docs (@Flimm)
• Make 'cli' support optional. Use pip install python-dotenv[cli]. (@theskumar)

0.8.0

• set_key and unset_key only modified the affected file instead of parsing and re-writing file, this causes comments and other file entact as it is.
• Add support for export prefix in the line.
• Internal refractoring (@theskumar)
• Allow load_dotenv and dotenv_values to work with StringIO()) (@alanjds)(@theskumar)(#78)

0.7.1

• Remove hard dependency on iPython (@theskumar)

0.7.0

• Add support to override system environment variable via .env. (@milonimrod) (#63)
• Disable ".env not found" warning by default (@maxkoryukov) (#57)

0.6.5

• Add support for special characters \. (@pjona) (#60)

0.6.4

• Fix issue with single quotes (@Flimm) (#52)

0.6.3

• Handle unicode exception in setup.py (#46)

0.6.2

• Fix dotenv list command (@ticosax)
• Add iPython Suport (@tillahoffmann)

0.6.0

• Drop support for Python 2.6
• Handle escaped charaters and newlines in quoted values. (Thanks @iameugenejo)
• Remove any spaces around unquoted key/value. (Thanks @paulochf)
• Added POSIX variable expansion. (Thanks @hugochinchilla)

0.5.1

• Fix find_dotenv - it now start search from the file where this function is called from.

0.5.0

• Add find_dotenv method that will try to find a .env file. (Thanks @isms)

0.4.0

• cli: Added -q/--quote option to control the behaviour of quotes around values in .env. (Thanks @hugochinchilla).
• Improved test coverage.