src/storage/fxfs/src/metrics.rs

// Copyright 2022 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

//!
//! The [`metrics`] module implements a non-intrusive way of recording filesystem-specific metrics.
//! Example usage:
//!
//!     use crate::metrics::IntMetric;
//!     let my_metric = IntMetric::new("metric_name", /*initial_value*/ 0);
//!     my_metric.set(5);
//!
//! Any metrics created will be available under the "fxfs/fs.detail" inspect node, which can be
//! queried by running `ffx inspect show bootstrap/fshost:root/fxfs`.
//!
//! The metric will remain available in the inspect tree until the metric object is dropped.
//!
//! Similar names to the property types from [`fuchsia_inspect`] are provided, but with `Property`
//! replaced with `Metric` to prevent any confusion. For example, [`metrics::IntMetric`] acts as a
//! drop-in replacement for [`fuchsia_inspect::IntProperty`]. The types provided in this module also
//! extend the functionality provided by [`fuchsia_inspect`].
//!
//! Metric collection on host builds is not supported, but a functionally equivalent stub
//! implementation is provided to allow the library to work cross-platform.
//!

pub mod traits;

//----------------------------------------------------------------------
// Platform-Specific Modules/Exports
//----------------------------------------------------------------------

// Export the stub implementations for non-Fuchsia builds.
#[cfg(not(target_os = "fuchsia"))]
mod stubs;
#[cfg(not(target_os = "fuchsia"))]
pub use stubs::*;

// Export the `fuchsia_inspect`-backed implementation on Fuchsia.
#[cfg(target_os = "fuchsia")]
pub use crate::platform::metrics::*;