Function try_read_sample 

pub fn try_read_sample(line: &str) -> Option<SampleData>

Tries to parse a &str line as a sample and returns SampleData containg the metric name, labels and value if it succeeds.

Examples:

use prometheus_wire::parser::{SampleData, LabelList, try_read_sample};
use std::collections::HashMap;

let line = r#"http_requests_total{method="post",code="200"} 1.5e3 1395066363000"#;
let opt_metric = try_read_sample(line);

let mut map = HashMap::new();
map.insert(String::from("method"), String::from("post"));
map.insert(String::from("code"), String::from("200"));

assert_eq!(
    opt_metric,
    Some(SampleData::new(
        String::from("http_requests_total"),
        LabelList::from_map(map),
        1500.0,
        Some(1395066363000))
    ));

let metric = opt_metric.unwrap();

assert_eq!(metric.labels.get_string("method"), Some(&String::from("post")));
assert_eq!(metric.labels.get_number("code"), Some(200.0));

assert_eq!(try_read_sample("# test"), None);