envr

Manipulate and transform .env files.

Use it

from envr import Envr

# load a file
e = Envr("/app/.env")

# load a stream
o = Envr(None, stream=sys.stdin)

# set keys, get values
e['NEW_KEY'] = e['OLD_KEY'] + e['OTHER_KEY']

# delete key
del e['OLD_KEY']

# save the changes
e.save()

Transforms

# returns an  OrderedDict
e_as_dict = e.dict()

# returns indented json
e_as_json = e.json()

# returns the in memory state, that is as close as possible to the
# original file format, perserving comments and incompatible lines
state = e.env()
state = str(e)

# returns an envr syntax-compatible, POSIX-compliant shell script as a
# string, containing only the variable assignments
e_as_strict_env = e.env(strict=True)

# turns off quoting of variable values
e_unquoted = e.env(quoted=False)
e_unquoted = e.env(strict=True, quoted=False)

# reads standard input, transforms it with Envr.env(strict=True), and writes
# the result to standard output
cat script.sh | python -m envr

`.env` envr syntax

.env syntax is a subset of POSIX shell scripts.

Each parseable line of the file contains a variable assignment of the form:

VARIABLE_NAME=VALUE COMMENT

NAME must match [a-zA-Z0-9_]+.

VALUE must match [^"'] if enclosed by one pair of any character in the set ["']; otherwise it must match [^\s"'].

COMMENT may be omitted, and if present must begin with a # after the space separating it from VALUE.

compatible with

.env envr syntax is compatible as a subset of .env files for

honcho
django-environ
python-dotenv (except for a bug with single quotes)

.env envr syntax generated by Envr(...).env(strict=True, quoted=False) is compatible as a subset of .env files for the above-listed projects as well as the following useful outlaying project, which does not parse quote pairs around values as of 2017-01-02.

docker-compose (This is a strange design choice for docker-compose because it parses assignments with a value beginning with space, i.e. NAME= FAIL, as if the space is the first byte of the value, which would not be compatible with POSIX-compliant shells, and all the things.)

known issue

If you do Envr(...).env(strict=True, quoted=False) and you have value that begins with a space, the outputted result, since it is not quoted, will not be compatible with POSIX-compliant shells. quoted=False was introduced in version 0.3.3 to support docker-compose, and should not be used unless necessary.