easy_utils/
random.rs

1use rand::{Rng};
2use rand::distributions::Alphanumeric;
3
4/// Generate random String with given charset of len length
5///
6/// # Example
7///
8/// ```
9/// const CHARSET: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ\
10///                     abcdefghijklmnopqrstuvwxyz\
11///                     0123456789)(*&^%$#@!~";
12/// const PASSWORD_LEN: usize = 30;
13/// let password = rust_utils::random::get_random_charset_string(PASSWORD_LEN, CHARSET);
14/// assert_eq!(password.len(), PASSWORD_LEN);
15/// for x in password.bytes() {
16///     assert!(CHARSET.contains(&x));
17/// }
18/// ```
19pub fn get_random_charset_string(len: usize, charset: &[u8]) -> String {
20    (0..len)
21        .map(|_| {
22            let idx = rand::thread_rng().gen_range(0..charset.len());
23            // It's safe, because `idx` is in `CHARSET`'s range.
24            char::from(unsafe { *charset.get_unchecked(idx) })
25        })
26        .collect()
27}
28
29/// Generate random String with alphanumeric(uppercase, lowercase & number) charset of len length
30///
31/// # Example
32///
33/// ```
34///const GEN_ASCII_STR_CHARSET: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ\
35///         abcdefghijklmnopqrstuvwxyz\
36///         0123456789";
37/// const PASSWORD_LEN: usize = 30;
38/// let password = rust_utils::random::get_random_alphanumeric_string(PASSWORD_LEN);
39/// assert_eq!(password.len(), PASSWORD_LEN);
40/// for x in password.bytes() {
41///     assert!(GEN_ASCII_STR_CHARSET.contains(&x));
42/// }
43/// ```
44pub fn get_random_alphanumeric_string(len: usize) -> String {
45    rand::thread_rng()
46        .sample_iter(&Alphanumeric)
47        .take(len)
48        .map(char::from)
49        .collect()
50}
51
52#[cfg(test)]
53mod tests {
54    use super::*;
55
56    #[test]
57    fn get_random_charset_string_test() {
58        const CHARSET: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ\
59                            abcdefghijklmnopqrstuvwxyz\
60                            0123456789)(*&^%$#@!~";
61        const PASSWORD_LEN: usize = 30;
62
63        let password = get_random_charset_string(PASSWORD_LEN, CHARSET);
64
65        assert_eq!(password.len(), PASSWORD_LEN);
66        for x in password.bytes() {
67            assert!(CHARSET.contains(&x));
68        }
69    }
70
71    #[test]
72    fn get_random_alphanumeric_string_test() {
73        const GEN_ASCII_STR_CHARSET: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ\
74                abcdefghijklmnopqrstuvwxyz\
75                0123456789";
76        const PASSWORD_LEN: usize = 30;
77
78        let password = get_random_alphanumeric_string(PASSWORD_LEN);
79        assert_eq!(password.len(), PASSWORD_LEN);
80        for x in password.bytes() {
81            assert!(GEN_ASCII_STR_CHARSET.contains(&x));
82        }
83    }
84}
easy_utils/random.rs

easy_utils/
random.rs
