polkadot_node_metrics/
lib.rs

1// Copyright (C) Parity Technologies (UK) Ltd.
2// This file is part of Polkadot.
3
4// Polkadot is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8
9// Polkadot is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12// GNU General Public License for more details.
13
14// You should have received a copy of the GNU General Public License
15// along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
16
17//! Metrics helpers
18//!
19//! Collects a bunch of metrics providers and related features such as
20//! `Metronome` for usage with metrics collections.
21//!
22//! This crate also reexports Prometheus metric types which are expected to be implemented by
23//! subsystems.
24
25#![deny(missing_docs)]
26#![deny(unused_imports)]
27
28pub use metered;
29
30/// Cyclic metric collection support.
31pub mod metronome;
32pub use self::metronome::Metronome;
33
34#[cfg(feature = "runtime-metrics")]
35pub mod runtime;
36#[cfg(feature = "runtime-metrics")]
37pub use self::runtime::logger_hook;
38
39/// Export a dummy logger hook when the `runtime-metrics` feature is not enabled.
40#[cfg(not(feature = "runtime-metrics"))]
41pub fn logger_hook() -> impl FnOnce(&mut sc_cli::LoggerBuilder, &sc_service::Configuration) {
42	|_logger_builder, _config| {}
43}
44
45/// This module reexports Prometheus types and defines the [`Metrics`](metrics::Metrics) trait.
46pub mod metrics {
47	/// Reexport Substrate Prometheus types.
48	pub use prometheus_endpoint as prometheus;
49
50	/// Subsystem- or job-specific Prometheus metrics.
51	///
52	/// Usually implemented as a wrapper for `Option<ActualMetrics>`
53	/// to ensure `Default` bounds or as a dummy type ().
54	/// Prometheus metrics internally hold an `Arc` reference, so cloning them is fine.
55	pub trait Metrics: Default + Clone {
56		/// Try to register metrics in the Prometheus registry.
57		fn try_register(
58			registry: &prometheus::Registry,
59		) -> Result<Self, prometheus::PrometheusError>;
60
61		/// Convenience method to register metrics in the optional Prometheus registry.
62		///
63		/// If no registry is provided, returns `Default::default()`. Otherwise, returns the same
64		/// thing that `try_register` does.
65		fn register(
66			registry: Option<&prometheus::Registry>,
67		) -> Result<Self, prometheus::PrometheusError> {
68			match registry {
69				None => Ok(Self::default()),
70				Some(registry) => Self::try_register(registry),
71			}
72		}
73	}
74
75	// dummy impl
76	impl Metrics for () {
77		fn try_register(
78			_registry: &prometheus::Registry,
79		) -> Result<(), prometheus::PrometheusError> {
80			Ok(())
81		}
82	}
83}
84
85#[cfg(all(feature = "runtime-metrics", not(feature = "runtime-benchmarks"), test))]
86mod tests;
polkadot_node_metrics/lib.rs

polkadot_node_metrics/
lib.rs
