2 unstable releases
0.2.0 | Jan 15, 2024 |
---|---|
0.1.0 | Mar 21, 2023 |
#557 in Configuration
41KB
1K
SLoC
potenv
A Rust implementation of the POSIX-compliant dotenv file format specification.
Usage
Load environment variables from a .env
file in the current working directory:
potenv::load([".env"]).expect("Failed to load .env file.");
For convenience, an iterator over the loaded variables is returned:
let vars = potenv::load([".env"]).unwrap();
for (name, value) in vars {
assert_eq!(value, std::env::var(name).unwrap());
}
If you just want to evaluate the dotenv files without loading them into the environment, use the following:
use potenv::Potenv;
let vars = Potenv::default()
.evaluate([".env"])
.unwrap();
By default, environment variables take precedence over variables defined in a dotenv file.
When this is not the desired behaviour, you can use the following:
use potenv::Potenv;
let vars = Potenv::default()
.override_env(true)
.load([".env"])
.unwrap();
If you don't want to read from and/or write to the process environment, you can implement the env::EnvProvider trait.
For example, this is how to frobnicate all variables:
use potenv::{Potenv, env::EnvProvider};
pub struct Frobnicator;
impl EnvProvider for Frobnicator {
fn var(&self, name: &str) -> Option<String> {
Some("frobnicated".into())
}
fn set_var(&mut self, name: &str, value: &str) {}
}
let vars = Potenv::new(Frobnicator, false)
.evaluate([".env"])
.unwrap();
for (name, value) in vars {
assert_eq!("frobnicated", value);
}
If you just want to mock the environment in unit-tests,
the env::EnvProvider trait is implemented for HashMap<String, String>
:
use std::collections::HashMap;
use potenv::Potenv;
let mut mock = HashMap::new();
mock.insert("name".into(), "value".into());
let vars = Potenv::new(mock, false)
.evaluate([".env"])
.unwrap();
Dependencies
~310–780KB
~18K SLoC