Loading .env files with no dependencies

Guy Waldman

July 26, 2024 (1 month ago)

Time to read:

2 minutes

#Problem

You have environment variables that you want to use in your project, and don't want to manually export them (and expose them in your shell history).
So you create a local (git ignoreD!) .env file that you wish to load into your BASH or ZSH shell session, that looks like so:

1MY_SECRET="super-secret-value"
2MY_OTHER_SECRET="other-secret-value"
3

You want a simple script which will load these variables into your shell session, and you don't want to install any dependencies to do this (e.g., dotenv-cli.

#Solution

1# Loads environment variables from a file into the current shell.
2# Usage: dotenv <env_file_path>
3function dotenv {
4	env_file_path="$1"
5
6	# Bail out if the file doesn't exist.
7	if [ ! -f "$env_file_path" ]; then
8		echo "Error: File '$env_file_path' does not exist." >&2
9		return 1
10	fi
11
12	echo "Loading environment variables from '$env_file_path...'"
13	# `sllexport`: Each variable or function that is created or modified is given the export attribute and marked for export to the environment of subsequent commands.
14	set -o allexport
15	source <(sed -e "s/\r//" -e '/^#/d;/^\s*$/d' -e "s/'/'\\\''/g" -e "s/=\(.*\)/=\"\1\"/g" "${env_file_path}")
16	set +o allexport
17
18	# Display the environment variables that were loaded.
19	env_vars=$(cat "$env_file_path" | grep -E '^[A-Z0-9_]+\s*=' | cut -d = -f 1 | tr '\n' ' ')
20	env_vars=($(echo $env_vars))
21	echo "Environment variables loaded from '$env_file_path': $(join_by ', ' $env_vars)"
22}
23

#References

stackoverflow.com/questions/9293887/how-to-read-a-space-delimited-string-into-an-array-in-bash

How to read a space-delimited string into an array in Bash?

I have a variable which contains a space-delimited string: line="1 1.50 string" I want to split that string with space...

0 answers