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Created March 22, 2017 13:34
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Parse a .env (dotenv) file directly using BASH
# Pass the env-vars to MYCOMMAND
eval $(egrep -v '^#' .env | xargs) MYCOMMAND
# … or ...
# Export the vars in .env into your shell:
export $(egrep -v '^#' .env | xargs)
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lzkill commented May 5, 2021

Why not dotenv-cli?

$ dotenv <command with arguments> 
# or
$ dotenv -e .env.custom <command with arguments>

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loopmode commented May 5, 2021

Because not every system has nodejs on it. And it's good that way.

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geoffjukes commented May 11, 2021

One-liner that allows unquoted variables that contain spaces:

OLD_IFS=$IFS; IFS=$'\n'; for x in `grep -v '^#.*' .env`; do export $x; done; IFS=$OLD_IFS

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ead_var() {
VAR=$(grep $1 $2 | xargs)
IFS="=" read -ra VAR <<< "$VAR"
echo ${VAR[1]}

MY_VAR=$(read_var MY_VAR .env)

Perfect, thanks

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What about this

# save the existing environment variables

# if the .env file exists, source it
[ -f .env ] && . .env

# re-export all vars from the env so they override what ever was set in .env
for e in $prevEnv
    export $e

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wieczorek1990 commented Jan 21, 2022

I wrote my own because was using forbidden symbols in envs.

This basically adds apostrophes so that all variables will be treated as strings. This way you can use your Docker env files and source them with source

import sys

def main(input_path, postfix='.sh'):
    with open(input_path, 'r') as file_handle:
        lines = file_handle.readlines()
        envs = {}
        for line in lines:
                parts = line.split('=')
                name = parts[0]
                value = ''.join(parts[1:]).rstrip('\n')
            except ValueError:
                envs[name] = value

    output_path = f'{input_path}{postfix}'
    with open(output_path, 'w') as file_handle:
        lines = []
        for name, value in envs.items():
            line = f'{name}=\'{value}\'\n'

if __name__ == '__main__':
    # Passes first argument as input path.

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andylamp commented Mar 12, 2023

The solution proposed by @arizonaherbaltea will not work correctly when the file is not terminated with a newline. For example using this .env example,

# test.env

Will not work properly, whereas the following will,

# test.env

The only change is adding a newline at the end of the file. This is because read requires a newline to parse the line correctly. Thus, in order to ensure everything works properly we can add a check to see if the file ends with newline and if not append it before parsing it. Doing this will ensure all lines are parsed correctly.


function export_envs() {
  local env_file=${1:-.env}
  local is_comment='^[[:space:]]*#'
  local is_blank='^[[:space:]]*$'
  echo "trying env file: ${env_file}"

  # ensure it has a newline that the end, if it does not already
  tail_line=`tail -n 1 "${env_file}"`
  if [[ "${tail_line}" != "" ]]; then
      echo "No Newline at end of ${env_file}, appending!"
      echo "" >> "${env_file}"

  while IFS= read -r line; do
    echo "${line}"
    [[ $line =~ $is_comment ]] && continue
    [[ $line =~ $is_blank ]] && continue
    key=$(echo "$line" | cut -d '=' -f 1)
    # shellcheck disable=SC2034
    value=$(echo "$line" | cut -d '=' -f 2-)
    # shellcheck disable=SC2116,SC1083
    echo "The key: ${key} and value: ${value}"
    eval "export ${key}=\"$(echo \${value})\""
  done < <(cat "${env_file}")

export_envs ${1}

Then it results,

✗ ./ test.env
trying env file: test.env
The key: MY_VAR and value: a
The key: MY_VAR and value: b

Hope this helps someone out there :)

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I've been using shdotenv from @ko1nksm and it's been great.

You can do shdotenv my-command to parse and run a command.
If you want to export the variables to the shell session, use eval $(shdotenv).

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tgrushka commented Feb 6, 2024

What's wrong with:

if [ -f .env ]; then
    set -o allexport
    source .env

Works on macOS with my .env that works with docker compose and does not have quotes around every string.

Test with:

envsubst < "$secret_file" | cat

later in the same script.

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