prometheus_wire/parser/
label.rs

1use std::collections::HashMap;
2use std::str::FromStr;
3
4/// List of labels for a [SampleData](super::SampleData). See examples at [try_read_sample](super::try_read_sample) for more details.
5#[derive(Debug, PartialEq)]
6pub struct LabelList(HashMap<String, String>);
7
8impl LabelList {
9    pub fn new() -> Self {
10        LabelList(HashMap::new())
11    }
12
13    pub fn from_map(h: HashMap<String, String>) -> Self {
14        LabelList(h)
15    }
16
17    /// tries to read a label as string.
18    pub fn get_string(&self, key: &str) -> Option<&String> {
19        self.0.get(key)
20    }
21
22    /// tries to read a label as a [`f64`], returning [`None`] if the label doesn't exist or cannot be represented as a [`f64`]
23    pub fn get_number(&self, key: &str) -> Option<f64> {
24        self.0.get(key).and_then(|s| match s.as_str() {
25            "+Inf" => Some(f64::INFINITY),
26            "-Inf" => Some(f64::NEG_INFINITY),
27            s => f64::from_str(&s).ok(),
28        })
29    }
30}
31
32impl Default for LabelList {
33    fn default() -> Self {
34        Self::new()
35    }
36}
37impl From<Vec<(&str, String)>> for LabelList {
38    fn from(input: Vec<(&str, String)>) -> Self {
39        let mut map = HashMap::with_capacity(input.len());
40
41        for (key, value) in input {
42            map.insert(key.to_string(), value);
43        }
44
45        LabelList(map)
46    }
47}
48
49#[cfg(test)]
50mod tests {
51    use crate::parser::label::LabelList;
52    use std::collections::HashMap;
53
54    #[test]
55    fn test_get_float() {
56        let mut m = HashMap::new();
57        m.insert("test1".into(), "1.5e-03".into());
58        m.insert("test2".into(), "-1.7560473e+07".into());
59        m.insert("test3".into(), "+Inf".into());
60        m.insert("test4".into(), "-Inf".into());
61        m.insert("test5".into(), "alfa".into());
62        m.insert("test6".into(), "".into());
63
64        let l = LabelList::from_map(m);
65
66        assert_eq!(l.get_number("test1"), Some(0.0015));
67        assert_eq!(l.get_number("test2"), Some(-17560473.0));
68        assert_eq!(l.get_number("test3"), Some(f64::INFINITY));
69        assert_eq!(l.get_number("test4"), Some(f64::NEG_INFINITY));
70        assert_eq!(l.get_number("test5"), None);
71        assert_eq!(l.get_number("test6"), None);
72    }
73}
prometheus_wire/parser/label.rs

prometheus_wire/parser/
label.rs
