Function prometheus_http_query::functions::label_replace

pub fn label_replace(
    vector: InstantVector, 
    dst_label: &str, 
    replacement: &str, 
    src_label: &str, 
    regex: &str
) -> Result<InstantVector, Error>

Apply the PromQL label_replace function.

use prometheus_http_query::{Selector, InstantVector};
use prometheus_http_query::functions::label_replace;
use std::convert::TryInto;

fn main() -> Result<(), prometheus_http_query::Error> {
    let vector: InstantVector = Selector::new()
        .metric("some_metric")?
        .with("some_label", "some_value")
        .try_into()?;

    let result = label_replace(vector, "new_label", "$1", "some_label", "(.*):.*")?;

    let promql = r#"label_replace(some_metric{some_label="some_value"}, "new_label", "$1", "some_label", "(.*):.*")"#;

    assert_eq!(&result.to_string(), promql);

    Ok(())
}