envious 0.3.0

Deserialize (potentially nested) environment variables into your custom structs
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75

#![allow(dead_code)]
use serde::Deserialize;

#[derive(Deserialize, Debug, PartialEq, Eq)]
enum Material {
    Wood,
    Plastic,
    Glass,
}

#[derive(Deserialize, Debug, PartialEq, Eq)]
struct Door {
    material: Material,
}

#[derive(Deserialize, Debug, PartialEq, Eq)]
struct UpstairsConfig {
    doors: Vec<Door>,
}

#[derive(Deserialize, Debug, PartialEq, Eq)]
struct Config {
    upstairs: UpstairsConfig,
}

#[test]
fn parse_from_env() {
    let vars = [
        ("ENVIOUS_upstairs__doors__0__material", ("Wood")),
        ("ENVIOUS_upstairs__doors__2__material", ("Glass")),
        ("ENVIOUS_upstairs__doors__1__material", ("Plastic")),
    ];

    let config: Config = envious::Config::new()
        .with_prefix("ENVIOUS_")
        .build_from_iter(vars)
        .unwrap();

    assert_eq!(
        config,
        Config {
            upstairs: UpstairsConfig {
                doors: vec![
                    Door {
                        material: Material::Wood
                    },
                    Door {
                        material: Material::Plastic
                    },
                    Door {
                        material: Material::Glass
                    }
                ]
            }
        }
    );

    // When case insensitive, the same test should succeed with a lowercase prefix.
    let config: Config = envious::Config::new()
        .case_sensitive(false)
        .with_prefix("envious_")
        .build_from_iter(vars)
        .unwrap();

    println!("{:#?}", config);

    // However when case sensitive, it will fail.
    let result: Result<Config, _> = envious::Config::new()
        .case_sensitive(true)
        .with_prefix("envious_")
        .build_from_iter(vars);
    let err = result.unwrap_err();

    println!("{:#?}", err);
}