Crate near_metrics

A fork of the lighthouse_metrics crate used to implement prometheus

A wrapper around the prometheus crate that provides a global, lazy_static metrics registry and functions to add and use the following components (more info at Prometheus docs):

• Histogram: used with start_timer(..) and stop_timer(..) to record durations (e.g., block processing time).
• IncCounter: used to represent an ideally ever-growing, never-shrinking integer (e.g., number of block processing requests).
• IntGauge: used to represent an varying integer (e.g., number of attestations per block).

Important

Metrics will fail if two items have the same name. All metrics must have a unique name. Because we use a global registry there is no namespace per crate, it’s one big global space.

See the Prometheus naming best practices when choosing metric names.

Example

#[macro_use]
extern crate lazy_static;
use near_metrics::*;

// These metrics are "magically" linked to the global registry defined in `lighthouse_metrics`.
lazy_static! {
    pub static ref RUN_COUNT: Result<IntCounter> = try_create_int_counter(
        "runs_total",
        "Total number of runs"
    );
    pub static ref CURRENT_VALUE: Result<IntGauge> = try_create_int_gauge(
        "current_value",
        "The current value"
    );
    pub static ref RUN_TIME: Result<Histogram> =
        try_create_histogram("run_seconds", "Time taken (measured to high precision)");
}


fn main() {
    for i in 0..100 {
        inc_counter(&RUN_COUNT);
        let timer = start_timer(&RUN_TIME);

        for j in 0..10 {
            set_gauge(&CURRENT_VALUE, j);
            println!("Howdy partner");
        }

        stop_timer(timer);
    }
}

Structs

Histogram	A Metric counts individual observations from an event or sample stream in configurable buckets. Similar to a Summary, it also provides a sum of observations and an observation count.
TextEncoder	An implementation of an Encoder that converts a MetricFamily proto message into text format.

Traits

Encoder

An interface for encoding metric families into an underlying wire protocol.

Functions

dec_gauge
gather	Collect all the metrics for reporting.
get_counter
inc_counter
inc_counter_by
inc_counter_by_opt
inc_counter_opt
inc_counter_vec
inc_gauge
observe	Sets the value of a Histogram manually.
set_gauge
start_timer	Starts a timer for the given Histogram, stopping when it gets dropped or given to stop_timer(..).
start_timer_vec	Starts a timer for the given HistogramVec and labels, stopping when it gets dropped or given to stop_timer(..).
stop_timer	Stops a timer created with start_timer(..).
try_create_histogram	Attempts to crate a Histogram, returning Err if the registry does not accept the counter (potentially due to naming conflict).
try_create_histogram_vec	Attempts to create a HistogramVector, returning Err if the registry does not accept the counter (potentially due to naming conflict).
try_create_int_counter	Attempts to crate an IntCounter, returning Err if the registry does not accept the counter (potentially due to naming conflict).
try_create_int_counter_vec	Attempts to crate an IntCounterVec, returning Err if the registry does not accept the counter (potentially due to naming conflict).
try_create_int_gauge	Attempts to crate an IntGauge, returning Err if the registry does not accept the counter (potentially due to naming conflict).

Type Definitions

HistogramVec	A Collector that bundles a set of Histograms that all share the same Desc, but have different values for their variable labels. This is used if you want to count the same thing partitioned by various dimensions (e.g. HTTP request latencies, partitioned by status code and method).
IntCounter	The integer version of Counter. Provides better performance if metric values are all positive integers (natural numbers).
IntCounterVec	The integer version of CounterVec. Provides better performance if metric are all positive integers (natural numbers).
IntGauge	The integer version of Gauge. Provides better performance if metric values are all integers.
Result	A specialized Result type for prometheus.