Load environment variables from dotenv / .env file in Bash

load_dotenv.sh

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

[ ! -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

this works for me

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

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

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

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

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

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

Sweet, works like a charm for me, thanks.

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

thank you this was better

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)