Function new 

pub fn new<F>(function: F) -> impl MetricValueProvider
where
    F: Fn(&MetricConfig, i64) -> MetricValue + Send + Sync,

A MetricValueProvider that calls function, standing in for a Java lambda implementing MetricValueProvider: function is value. A method Java adds later as an overload of value gets its own factory, with_<parameter>.

Arguments

• function - computes the value from the config and the time in milliseconds

Returns

The provider calling function.

use confluent_kafka::common::MetricValue;
use confluent_kafka::common::metrics::{metric_value_provider, Metrics};

let metrics = Metrics::new();
let name = metrics.metric_name("uptime-ms", "example");
let provider = metric_value_provider::new(|_config, now| MetricValue::Double(now as f64));
metrics.add_metric_with_metric_value_provider(name, Box::new(provider)).unwrap();