`set_key` does not handle single quote `'` inside value properly
Author: YuryHrytsukCreated Dec 17, 2024Updated Aug 16, 2026
Problem
set_key function does not properly handle single quote ' inside value.
python-dotenv version: 1.0.1
Related PR
- https://github.com/theskumar/python-dotenv/pull/330 (https://github.com/theskumar/python-dotenv/pull/330#discussion_r669439596)
How to reproduce
- Run python script below
- Run
source .env
Python Script
from dotenv import set_key
def main():
var_value = "I'm a bug :("
set_key(".env", "VAR", var_value)
if __name__ == "__main__":
main()Error from source .env
bash: .env: line 1: syntax error near unexpected token `('
bash: .env: line 1: `VAR='I\'m a bug :(''Example of fix
:warning: this fix produces values that dotenv cannot parse (see this issue) :warning:
from dotenv import set_key
def fixed_set_key(file_path, key, value):
# properly escape ' if present
# https://stackoverflow.com/questions/8254120/how-can-i-escape-a-single-quote-in-a-single-quote-string-in-bash/26165123#26165123
value = value.replace("'", "'\"'\"'")
set_key(file_path, key, f"'{value}'", quote_mode="never")
def main():
var_value = "I'm a fixed :)"
fixed_set_key(".env", "VAR", var_value)
if __name__ == "__main__":
main()Source: theskumar/python-dotenv