prometheus-macros offers advanced macros for defining prometheus metrics.
This crate extends prometheus by introducing declarative macros that minimize
boilerplate during the declaration and initialization of metrics. Multiple metrics
are often needed, as seen for example in contexts like HTTP request
where one needs to declare distinct metrics for request count and request latency.
Although prometheus already offers
declarative macros for initializing individual metrics, it can still lead to significant
boilerplate when declaring multiple metrics.
```rust use prometheus::{IntGauge, HistogramVec}; use prometheusmacros::compositemetric;
compositemetric! { struct CompositeMetric { #[name = "customgauge"] #[desc = "Example gauge metric"] customgauge: IntGauge, #[name = "customhistvec"] #[desc = "Example histogram vec"] #[labels = ["foo", "bar"]] #[buckets = [0.01, 0.1, 0.2]] customhist_vec: HistogramVec, } }
fn main() { let metric = CompositeMetric::register(prometheus::defaultregistry()) .expect("failed to register metrics to default registry"); // access the metrics metric.customgauge().set(420); metric.customhistvec().withlabelvalues(&["a", "b"]).observe(0.5); } ```