twelf 0.15.0

Twelf is a configuration solution for Rust including 12-Factor support. It is designed with layers in order to configure different sources and formats to build your configuration. The main goal is to be very simple using a proc macro.
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
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134

#![cfg(feature = "json")]

use std::collections::HashMap;
use config_derive::config;
use twelf::Layer;

fn default_array() -> Vec<String> {
    vec!["first".to_owned(), "second".to_owned()]
}

const JSON_TEST_FILE: &str = "./tests/fixtures/test.json";

#[test]
fn json_simple_types() {
    #[config]
    #[derive(Debug, Default)]
    struct TestCfg {
        test: String,
        another: usize,
    }
    std::env::set_var("ANOTHER", "5");
    let prio = vec![Layer::Json(JSON_TEST_FILE.into()), Layer::Env(None)];
    let config = TestCfg::with_layers(&prio).unwrap();
    assert_eq!(config.test, String::from("from file"));
    assert_eq!(config.another, 5usize);

    let prio = vec![Layer::Env(None), Layer::Json(JSON_TEST_FILE.into())];
    let config = TestCfg::with_layers(&prio).unwrap();
    assert_eq!(config.test, String::from("from file"));
    assert_eq!(config.another, 25usize);
}

#[test]
fn json_simple_with_prefix() {
    #[config]
    #[derive(Debug, Default)]
    struct Conf {
        elements_def: HashMap<String, String>,
        #[serde(default = "default_array")]
        array_def: Vec<String>,
    }

    std::env::set_var("APP_ELEMENTS_DEF", "coucou=toi,hello=you");
    let prio = vec![
        Layer::Json(JSON_TEST_FILE.into()),
        Layer::Env(Some("APP_".to_string())),
    ];
    let config = Conf::with_layers(&prio).unwrap();
    let mut map = HashMap::new();
    map.insert("coucou".to_string(), "toi".to_string());
    map.insert("hello".to_string(), "you".to_string());

    assert_eq!(config.elements_def, map);
    let array = vec![String::from("first"), String::from("second")];
    assert_eq!(config.array_def, array);
}

#[test]
fn json_simple_with_option() {
    #[config]
    #[derive(Debug, Default)]
    struct Conf {
        elements_def: Option<HashMap<String, String>>,
        array_def: Option<Vec<String>>,
    }

    std::env::set_var("APPBIS_ELEMENTS_DEF", "coucou=toi,hello=you");
    let prio = vec![
        Layer::Json(JSON_TEST_FILE.into()),
        Layer::Env(Some("APPBIS_".to_string())),
    ];
    let config = Conf::with_layers(&prio).unwrap();
    let mut map = HashMap::new();
    map.insert("coucou".to_string(), "toi".to_string());
    map.insert("hello".to_string(), "you".to_string());

    assert_eq!(config.elements_def, Some(map));
    assert_eq!(config.array_def, None);
}

#[test]
fn json_with_array_and_hashmap_string() {
    #[config]
    #[derive(Debug, Default)]
    struct Conf {
        elements: HashMap<String, String>,
        #[serde(default = "default_array")]
        array: Vec<String>,
    }

    std::env::set_var("ARRAY", "test,test2");
    std::env::set_var("ELEMENTS", "coucou=toi,hello=you");
    let prio = vec![Layer::Json(JSON_TEST_FILE.into()), Layer::Env(None)];
    let config = Conf::with_layers(&prio).unwrap();
    let mut map = HashMap::new();
    map.insert("coucou".to_string(), "toi".to_string());
    map.insert("hello".to_string(), "you".to_string());

    assert_eq!(config.elements, map);
    let array = vec![String::from("test"), String::from("test2")];
    assert_eq!(config.array, array);

    let mut map = HashMap::new();
    map.insert("key".to_string(), "value".to_string());
    map.insert("key2".to_string(), "value2".to_string());

    let prio = vec![Layer::Env(None), Layer::Json(JSON_TEST_FILE.into())];
    let config = Conf::with_layers(&prio).unwrap();
    assert_eq!(config.elements, map);
    let array = vec![String::from("test"), String::from("test2")];
    assert_eq!(config.array, array);
}

#[test]
fn json_with_array_and_hashmap_with_default() {
    #[config]
    #[derive(Debug, Default)]
    struct Conf {
        elements_def: HashMap<String, String>,
        #[serde(default = "default_array")]
        array_def: Vec<String>,
    }

    std::env::set_var("ELEMENTS_DEF", "coucou=toi,hello=you");
    let prio = vec![Layer::Json(JSON_TEST_FILE.into()), Layer::Env(None)];
    let config = Conf::with_layers(&prio).unwrap();
    let mut map = HashMap::new();
    map.insert("coucou".to_string(), "toi".to_string());
    map.insert("hello".to_string(), "you".to_string());

    assert_eq!(config.elements_def, map);
    let array = vec![String::from("first"), String::from("second")];
    assert_eq!(config.array_def, array);
}