INSTALLATION

[dependencies]
granular-metrics = "0.2.1"

Or with optional actix-web HTTP endpoint

[dependencies]
granular-metrics = { version = "0.2.1", features = ["http"] }

HOW TO USE

ONE: Define

#[derive(serde::Serialize)] is only needed for the http feature
#[derive(Debug, Clone, PartialEq, Eq, Hash)] is mandatory

#[derive(Debug, Clone, PartialEq, Eq, Hash, serde::Serialize)]
enum Keys {
    Login,
    Download,
    Ping,
    Verify,
}

• Choose any name for the enum type
• Each variant corresponds to a key and may be named however you like
• There’s no limit on how many keys (variants) you define

TWO: Initialize

#[tokio::main]
async fn main() {
    granular_metrics::init::<Keys>();
}

Or with the actix-web HTTP feature

#[tokio::main]
async fn main() {
    granular_metrics::init::<Keys>("127.0.0.1", "8080", "metrics", "all");
}

pub fn init<K>(address: &str, port: &str, path: &str, workers: &str)
http://127.0.0.1:8080/metrics

• address: The IP address on which the HTTP server will listen
• port: The port number to listen on
• path: The URL segment (without leading slash) that is exposed
• workers: How many actix-web worker threads to spawn
  • A value of "all" or "" will spawn the default amount (matches the number of CPU cores)
  • Or give it a specific number, such as "2"

THREE: INCREMENT

Call the increment(Keys::Variant) function to increase that key’s counter by one

use crate::Keys::*;
use granular_metrics::increment;

async fn login_handler() -> impl Responder {
    increment(Login);
}

async fn download_handler() -> impl Responder {
    increment(Download);
}

FOUR: Retrieve

fn main() {
    let server_metrics = granular_metrics::fetch::<Keys>();
}

Or with the actix-web HTTP feature

curl http://127.0.0.1:8080/metrics

// Make a custom implementation to retrieve and store your data

What you are retrieving:

pub struct MetricsSnapshot<K> {
    pub per_key: HashMap<K, (u64, u64)>,
    pub total: (u64, u64),
}

MetricsSnapshot { per_key: {Login: (8, 500), Download: (0, 10), Ping: (1, 100), Verify: (16, 1000)}, total: (26, 1610) }

Or the JSON version when using the HTTP feature

{"per_key":{"Login":[1,95],"Download":[0,3],"Ping":[2,179],"Verify":[0,20]},"total":[4,297]}

This translates to

{ per_key: {Login: (requests per second, requests per minute), Download: (RPS, RPM), Ping: (RPS, RPM), Verify: (RPS, RPM)}, total: (aggregate RPS: total requests last minute ÷ 60, aggregate RPM: total requests last minute) }

INFORMATION

• Both the per second and per minute calculations are computed every second
  • "Real time" metrics are possible