Helper libary to export prometheus metrics using hyper. It's intended to help writing prometheus exporters without the need to setup and maintain a http webserver. If the program also uses a http server for other purposes this package is probably not the best way and rust-prometheus should be used directly.
It uses rust-prometheus for collecting and rendering the prometheus metrics and hyper for exposing the metrics through http.
NOTICE: You have to use the same prometheus crate version that is used by
this crate to make sure that the global registrar use by the prometheus macros
works as expected. This crate re-exports the prometheuse crate to make it easier
to keep versions in sync (see examples). Currently this crate uses prometheus
version 0.9.
Add this to your Cargo.toml:
toml
[dependencies]
prometheus_exporter = "0.5"
There are three ways on how to use the exporter:
PrometheusExporter::run: Just starts the hyper http server and exports
metrics from the global prometheus register under the path /metrics.
Allows the most freedom on how and when to update/generate metrics.
PrometheusExporter::run_and_notify: Starts the http server and opens
channels to allow notification of when a request is made. This is usefull
for cases where metrics should be updated everytime somebody calls the
/metrics path.
PrometheusExporter::run_and_repeat: Starts the http server and opens
channels that will send a message to the original caller when a duration
inteval is reached. This will be repeated forever. This is usefull for cases
where metrics should be gathered in a set interval. For example if the
metric collection is expensive it makes more sense to not collect the
metrics all the time.
For examples on how to use prometheus_exporter see the examples folder.
A very simple example looks like this (from examples/simple/src/main.rs):
```rust // Will create an exporter with a single metric that does not change
use envlogger::{ Builder, Env, }; use prometheusexporter::{ PrometheusExporter, prometheus::register_gauge, }; use std::net::SocketAddr;
fn main() { // Setup logger with default level info so we can see the messages from // prometheusexporter. Builder::fromenv(Env::default().defaultfilteror("info")).init();
// Parse address used to bind exporter to.
let addr_raw = "0.0.0.0:9184";
let addr: SocketAddr = addr_raw.parse().expect("can not parse listen addr");
// Create metric
let metric =
register_gauge!("the_answer", "to everything").expect("can not create gauge the_answer");
metric.set(42.0);
// Start exporter and makes metrics available under http://0.0.0.0:9184/metrics
PrometheusExporter::run(&addr).expect("can not run exporter");
} ```