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@mihow
Last active December 6, 2024 03:28
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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
@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

@rjchicago
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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

As @richarddewit pointed out above, -a/+a can be used in place of -o allexport to be more concise (thanks!).

I now use the following simple line to source .env files into my scripts...

set -a; source .env; set +a

@miedza
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miedza commented Sep 29, 2022

export $(awk -F= '{output=output" "$1"="$2} END {print output}' aaa.env)

@bergpb
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bergpb commented Dec 9, 2022

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

Sweet, works like a charm for me, thanks.

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

thank you this was better

@C-Duv
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C-Duv commented Jan 20, 2023

I had troubles with a (Docker) setup where environment variables had spaces in their value without quotes and I needed to get the container's env. vars. in a script called during the container execution/runtime.

I ended getting the variables in the entrypoint, exporting them to a file and them reading them when needed.

# In entrypoint
export -pn \
    | grep "=" \
    | grep -v -e PATH -e PWD -e OLDPWD \
    | cut -d ' ' -f 3- \
    > /docker-container.env

The export command fixes issues with missing quotes, avoiding errors where the shell interpreter tries to execute parts of the variable value as commands.

# In script
set -o allexport
. /docker-container.env
set +o allexport

(I had to use /bin/sh so not using source file but . file)

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

Fantastic! Thanks @n1k0!

@spazm
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spazm commented Mar 1, 2023

Posix compliant version built around set, [ ] and . Many thanks to the prior posters who brought up set -o a and set -a / set +a

This snippet will source a dotenv file, exporting the values into the environment. If allexport is already set, it leaves it set, otherwise it sets, reads, and unsets.

if [ -z "${-%%*a*}" ]; then
    set -a
    . ./.env
    set +a
else
    . ./.env
fi

double brackets [[, source, setopt are not available in posix. Nor is the test [[ -o a ]] to check for set options. And we need to quote our comparison strings to deal with empty vars.

The code to check if an option is set is a bit of a pain. It could be a case statement or a grep on set -o like set -o | grep allexport | grep -q yes, but blech. Instead I've used parameter expansion with pattern matching to remove a maximum match from the $- variable containing a single line of the set options.

${-%%*a*} uses %% parameter expansion to remove the longest suffix matching the pattern *a*. If $- contains a then this expansion produces and empty string which we can test with -z or -n.

subtle bug if no options are set, so the comparison "$-" = "${-%%a*}" will check that the expansion changed the string. allexport is set if the two strings differ. And even % will work as we don't need a maximal match and can remove the leading * from our pattern match.

if [ "$-" = "${-%a*}" ]; then
    # allexport is not set
    set -a
    . ./.env
    set +a
else
    . ./.env
fi

@guillermodlpa
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When the values have newline chars \n, spaces or quotes, it can get messy.

After a lot of trial and error, I ended up with a variation of what @bergkvist proposed in https://gist.github.com/mihow/9c7f559807069a03e302605691f85572?permalink_comment_id=4245050#gistcomment-4245050 (thank you very much!).

ENV_VARS="$(cat .env | awk '!/^\s*#/' | awk '!/^\s*$/')"

eval "$(
  printf '%s\n' "$ENV_VARS" | while IFS='' read -r line; do
    key=$(printf '%s\n' "$line"| sed 's/"/\\"/g' | cut -d '=' -f 1)
    value=$(printf '%s\n' "$line" | cut -d '=' -f 2- | sed 's/"/\\\"/g')
    printf '%s\n' "export $key=\"$value\""
  done
)"

@khoahuynhdev
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env $(cat .env)
this does not work for me but this one works

env $(cat .env|xargs) CMD

my .env has some special value such as FOO='VPTO&wH7$^3ZHZX$o$udY4&i'
@NatoBoram

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