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@mihow
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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
@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.

@BinitaBharati
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source .env

works for me

wont work if you have # in your .env

Thanks for this.

@xswirelab
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@devzom
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devzom commented Mar 16, 2022

Great work ! :)

  • I have .env with [VAR1=xyz, VAR2=233, NPM_TOKEN=123]

  • Seems that this example from @valmayaki :

if [ -f .env ]; then
  export $(echo $(cat .env | sed 's/#.*//g'| xargs) | envsubst)
fi
# always response as one liner with all the variables
  • I switched to use this without xargs:
export "$(grep -vE "^(#.*|\s*)$" .env)"
# as it's responding with single value ex: 
echo $NPM_TOKEN # just print the single variable

thanks to all for great cooperation <3

@michchan
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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

This works!

@alphanetEX
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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

Many thanks for this solution reference

@theofanisv
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That 's great, thanks

@wffranco
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wffranco commented Jun 29, 2022

@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

this read line by line, allowing to use previous set variables

  while read -r LINE; do
    if [[ $LINE == *'='* ]] && [[ $LINE != '#'* ]]; then
      ENV_VAR="$(echo $LINE | envsubst)"
      eval "declare $ENV_VAR"
    fi
  done < .env

@Krong1997
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@wffranco

@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

this read line by line, allowing to use previous set variables

  while read -r LINE; do
    if [[ $LINE == *'='* ]] && [[ $LINE != '#'* ]]; then
      ENV_VAR="$(echo $LINE | envsubst)"
      eval "declare $ENV_VAR"
    fi
  done < .env

This solution is helpful!
Thanks a lot!

@bergkvist
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bergkvist commented Jul 26, 2022

You can also do:

eval "$(
  cat .env | awk '!/^\s*#/' | awk '!/^\s*$/' | while IFS='' read -r line; do
    key=$(echo "$line" | cut -d '=' -f 1)
    value=$(echo "$line" | cut -d '=' -f 2-)
    echo "export $key=\"$value\""
  done
)"

This ignores empty lines, and lines starting with # (comments). If you replace eval with echo - you can inspect the generated code.

@richarddewit
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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

From man set:

       -o option
             This  option  is  supported if the system supports the User Portability Utilities op‐
             tion. It shall set various options, many of which shall be equivalent to  the  single
             option letters. The following values of option shall be supported:

             allexport Equivalent to -a.

So this is the same as

set -a            
source .env
set +a

@jairajsahgal
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[ ! -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)

This one works for django .env

@SrEnrique
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this works for me

#!/usr/bin/env bash
. .env

@drjasonharrison
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For those using sed to rewrite their .env files before evaluation by bash, for example the solution suggested by @kolypto in https://gist.github.com/mihow/9c7f559807069a03e302605691f85572?permalink_comment_id=3625310#gistcomment-3625310

I ran into another case that hadn't been considered: Windows line endings "\r\n". I'm now using:

    set -o allexport # enable all variable definitions to be exported
    source <(sed -e "s/\r//" -e '/^#/d;/^\s*$/d' -e "s/'/'\\\''/g" -e "s/=\(.*\)/=\"\1\"/g" "${ENV_FILE}")
    set +o allexport

@bolorundurovj
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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

From man set:

       -o option
             This  option  is  supported if the system supports the User Portability Utilities op‐
             tion. It shall set various options, many of which shall be equivalent to  the  single
             option letters. The following values of option shall be supported:

             allexport Equivalent to -a.

So this is the same as

set -a            
source .env
set +a

Worked for me

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