pub mod env_var {
use regex::Regex;
use serde::{Deserialize, Deserializer};
use std::net::SocketAddr;
use std::path::PathBuf;
#[derive(Deserialize, PartialEq)]
struct WrappedString(String);
pub fn str<'de, D>(deserializer: D) -> Result<String, D::Error>
where
D: Deserializer<'de>,
{
let value = String::deserialize(deserializer)?;
match is_env_var(&value) {
true => Ok(get_env_var(&value)),
false => Ok(value),
}
}
pub fn opt_str<'de, D>(deserializer: D) -> Result<Option<String>, D::Error>
where
D: Deserializer<'de>,
{
Option::<WrappedString>::deserialize(deserializer).map(|option: Option<WrappedString>| {
option.map(|wrapped: WrappedString| {
let value = wrapped.0;
match is_env_var(&value) {
true => get_env_var(&value),
false => value,
}
})
})
}
pub fn socket_addr<'de, D>(deserializer: D) -> Result<SocketAddr, D::Error>
where
D: Deserializer<'de>,
{
let value = String::deserialize(deserializer)?;
match is_env_var(&value) {
true => Ok(get_env_var(&value).parse().unwrap()),
false => Ok(value.parse().unwrap()),
}
}
pub fn path_buf<'de, D>(deserializer: D) -> Result<PathBuf, D::Error>
where
D: Deserializer<'de>,
{
let value = String::deserialize(deserializer)?;
match is_env_var(&value) {
true => Ok(PathBuf::from(get_env_var(&value))),
false => Ok(PathBuf::from(value)),
}
}
fn is_env_var(value: &str) -> bool {
Regex::new(r"^\$\{env\.\w+\}$")
.expect("env_var: regex is invalid")
.is_match(value)
}
fn get_env_var(wrapped_key: &str) -> String {
let key: String = String::from(wrapped_key)
.drain(6..(wrapped_key.len() - 1))
.collect();
std::env::var(&key).unwrap_or_else(|_| panic!("env_var: variable '{key}' is not set"))
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn it_checks_environment_variable_patterns() {
assert!(is_env_var("${env.XXX}"));
assert!(!is_env_var("${env.XXX"));
assert!(!is_env_var("${env.XXX}a"));
assert!(!is_env_var("a${env.XXX}"));
assert!(!is_env_var("{env.XXX}"));
assert!(!is_env_var("$env.XXX}"));
assert!(!is_env_var("${envXXX}"));
assert!(!is_env_var("${.XXX}"));
assert!(!is_env_var("${XXX}"));
}
#[test]
fn it_gets_environment_variable() {
unsafe { std::env::set_var("TEST", "test") };
assert_eq!(get_env_var("${env.TEST}"), "test");
unsafe { std::env::remove_var("TEST") };
}
}
}