BasicOIDC/src/utils/string_utils.rs

use lazy_regex::regex_find;
use rand::distr::{Alphanumeric, SampleString};

/// Generate a random string of a given size
pub fn rand_str(len: usize) -> String {
    Alphanumeric.sample_string(&mut rand::rng(), len)
}

/// Parse environment variables
pub fn apply_env_vars(val: &str) -> String {
    let mut val = val.to_string();

    if let Some(varname_with_wrapper) = regex_find!(r#"\$\{[a-zA-Z0-9_-]+\}"#, &val) {
        let varname = varname_with_wrapper
            .strip_prefix("${")
            .unwrap()
            .strip_suffix('}')
            .unwrap();
        let value = match std::env::var(varname) {
            Ok(v) => v,
            Err(e) => {
                log::error!("Failed to find environment variable {varname}!");
                eprintln!("Failed to find environment variable! {e:?}");
                std::process::exit(2);
            }
        };

        val = val.replace(varname_with_wrapper, &value);
    }

    val
}

/// Check out whether a given login is acceptable or not
pub fn is_acceptable_login(login: &str) -> bool {
    mailchecker::is_valid(login) || lazy_regex::regex!("^[a-zA-Z0-9-+]+$").is_match(login)
}

#[cfg(test)]
mod test {
    use crate::utils::string_utils::{apply_env_vars, is_acceptable_login};
    use std::env;

    const VAR_ONE: &str = "VAR_ONE";
    #[test]
    fn test_apply_env_var() {
        unsafe {
            env::set_var(VAR_ONE, "good");
        }
        let src = format!("This is ${{{}}}", VAR_ONE);
        assert_eq!("This is good", apply_env_vars(&src));
    }

    const VAR_INVALID: &str = "VAR_INV@LID";

    #[test]
    fn test_invalid_var_syntax() {
        let src = format!("This is ${{{}}}", VAR_INVALID);
        assert_eq!(src, apply_env_vars(&src));
    }

    #[test]
    fn test_is_acceptable_login() {
        assert!(is_acceptable_login("admin"));
        assert!(is_acceptable_login("someone@somewhere.fr"));
        assert!(!is_acceptable_login("someone@somewhere.#fr"));
        assert!(!is_acceptable_login("bad bad"));
    }
}