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@mihow
Last active September 16, 2024 17:00
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Load environment variables from dotenv / .env file in Bash
# The initial version
if [ ! -f .env ]
then
export $(cat .env | xargs)
fi
# My favorite from the comments. Thanks @richarddewit & others!
set -a && source .env && set +a
@ko1nksm
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ko1nksm commented Apr 12, 2021

Seeing that this thread has been going on for long years, I figured we need a dotenv tool for the shell.

And I wrote it.
https://github.com/ko1nksm/shdotenv

There is no formal specification for .env, and each is slightly different, but shdotenv supports them and correctly parses comments, whitespace, quotes, etc. It is a single file shell script that requires only awk and runs lightly.

There is no need to waste time on trial and error anymore.

@asheroto
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Seeing that this thread has been going on for long years, I figured we need a dotenv tool for the shell.

And I wrote it.
https://github.com/ko1nksm/shdotenv

There is no formal specification for .env, and each is slightly different, but shdotenv supports them and correctly parses comments, whitespace, quotes, etc. It is a single file shell script that requires only awk and runs lightly.

There is no need to waste time on trial and error anymore.

This is great!

@mihow
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Author

mihow commented Apr 13, 2021

Wow @ko1nksm! This looks incredibly thorough. I look forward to using it, thank you.

@GusGA
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GusGA commented Apr 17, 2021

FWIW - I found this helpful, but it didn't do what I had expected. Modified it slightly to result in the following.

if [ -f .env ]
then
  export $(cat .env | sed 's/#.*//g' | xargs)
fi

👍 * 100

@lionelkouame
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Thank you so much for your solution .

@muthugit
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muthugit commented May 4, 2021

source .env

works for me

@abhidp
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abhidp commented May 28, 2021

source .env

works for me

wont work if you have # in your .env

@muthugit
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@abhidp sorry, i didn't check that case...

@Bioblaze
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Bioblaze commented Jun 6, 2021

# Local .env
if [ -f .env ]; then
    # Load Environment Variables
    export $(cat .env | grep -v '#' | sed 's/\r$//' | awk '/=/ {print $1}' )
fi

is what I use.. <.< it allows me to comment inside of the .env file :X and handles /r proper.. hope that helps everyone <3

@Bashorun97
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Here is a modified version of this code that allows for variable expansion

if [ -f .env ]; then
  export $(echo $(cat .env | sed 's/#.*//g'| xargs) | envsubst)
fi

This worked for me. Thanks

@quilicicf
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Went for:

loadEnv() {
  local envFile="${1?Missing environment file}"
  local environmentAsArray variableDeclaration
  mapfile environmentAsArray < <(
    grep --invert-match '^#' "${envFile}" \
      | grep --invert-match '^\s*$'
  ) # Uses grep to remove commented and blank lines
  for variableDeclaration in "${environmentAsArray[@]}"; do
    export "${variableDeclaration//[$'\r\n']}" # The substitution removes the line breaks
  done
}

It does not glob or swallow quotes, tested with:

WITH_QUOTES=''

# Comment
WITNESS=whatever

WITH_GLOB=*.sh

In this folder (so the glob matches the shell file):

.
├── .env
└── loadEnvTest.sh

With command:

source ./loadEnvTest.sh; loadEnv .env; echo "$WITH_QUOTES $WITH_GLOB"

Outputs:

'' *.sh

@maxweber3
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darbe habercisi

@msmans
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msmans commented Jul 31, 2021

One I use (bash specific) which behaves correctly in presence of calling environment override:

. <(sed -n 's/^\([^#][^=]*\)=\(.*\)$/\1=${\1:-\2}/p' .env 2>/dev/null) || true

@shlomi-viz
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if [ ! -f .env ]
then
  export $(cat .env | xargs)
fi

I hate bash so much...... it took me 30 minutes to understand it should be if [ -f .env ] instead of if [ ! -f .env ] 😢

@chengxuncc
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chengxuncc commented Aug 26, 2021

[ ! -f .env ] || export $(sed 's/#.*//g' .env | xargs)

Update:
TEXT="abc#def" not work as expected, so just replace line begin with #.

[ ! -f .env ] || export $(grep -v '^#' .env | xargs)

@ShivKJ
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ShivKJ commented Aug 30, 2021

@chengxuncc

using export $(grep -v '^#' .env | xargs) could not export the following,

A=10
B=$A
C=${A}

now, echo $B produces $A while it should print 10

@chengxuncc
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@chengxuncc

using export $(grep -v '^#' .env | xargs) could not export the following,

A=10
B=$A
C=${A}

now, echo $B produces $A while it should print 10

@ShivKJ Of course, it will equal to export A=10 B=$A C=${A} and doesn't work like shell script. Another example is /etc/environment have same behavior and don't accept variable definition.

@kolypto
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kolypto commented Sep 12, 2021

If you're wondering how to load a .env file with direnv: direnv already supports that :)

dotenv "testing.env"

Docs: https://direnv.net/man/direnv-stdlib.1.html

@jhud
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jhud commented Sep 20, 2021

The Problem

The problem with .env files is that they're like bash, but not completely.
While in bash you'd sometimes put quotes around values:

name='value ! with > special & characters'

in .env files there are no special characters, and quotes are not supported: they're part of the value. As a result, such a string has to be escaped when imported into bash.

The Solution

This version withstands every special character in values:

set -a
source <(cat development.env | sed -e '/^#/d;/^\s*$/d' -e "s/'/'\\\''/g" -e "s/=\(.*\)/='\1'/g")
set +a

Explanation:

  • -a means that every bash variable would become an environment variable
  • /^#/d removes comments (strings that start with #)
  • /^\s*$/d removes empty strings, including whitespace
  • "s/'/'\\\''/g" replaces every single quote with '\'', which is a trick sequence in bash to produce a quote :)
  • "s/=\(.*\)/='\1'/g" converts every a=b into a='b'

As a result, you are able to use special characters :)

To debug this code, replace source with cat and you'll see what this command produces.

Thank you! I have some long and unusually formatted environment variables, and this was the only solution which didn't choke on them.

@jquick
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jquick commented Sep 21, 2021

~/bin/envs

set -a
source .env
set +a
exec $@

$> envs go run .

@lsotoj
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lsotoj commented Sep 21, 2021

export $(grep -v '^#' .env | xargs)

Thanks so much. I love it.

@aslamanver
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export $(grep -v '^#' .env | xargs)

Hats off man

@xmarkclx
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xmarkclx commented Oct 7, 2021

Doesn't work for me because of JWT in the .env with lots of newlines.
Had to manually vim copy paste the contents instead.

@nickbien
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this worked for me, from @rjchicago snippet
set -o allexport; source .env; set +o allexport

@geekwhocodes
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Here is a modified version of this code that allows for variable expansion

if [ -f .env ]; then
  export $(echo $(cat .env | sed 's/#.*//g'| xargs) | envsubst)
fi

worked like a charm. Thanks!

@NatoBoram
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FWIW If you need to just run a command with environment from an env file, this could help:

env $(cat .env|xargs) CMD

provided there are no other lines except env definitions in form of VAR=VALUE. Don't remember where I found it, but does the trick for me.

You can actually get away without xargs

env $(cat .env) <command>

@fzancan-SpazioCodice
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export $( grep -vE "^(#.*|\s*)$" .env )

@J5Dev
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J5Dev commented Nov 8, 2021

The cleanest solution I found for this was using allexport and source like this

set -o allexport
source .env set
+o allexport

This was by far the best solution here for me, removed all the complexity around certain chars, spaces comments etc. Just needed a tweak on formatting to prevent others being tripped up, should be:

set -o allexport
source .env
set +o allexport

@MrYutz
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MrYutz commented Nov 11, 2021

The above worked fine for me, but thought I'd share the solution I went with: https://stackoverflow.com/a/30969768/179329 set -o allexport; source .env; set +o allexport

I like this too.

@n1k0
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n1k0 commented Mar 1, 2022

oh-my-zsh users can also activate the dotenv plugin.

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