enhancement: add a new DogStatsD-specific exporter (#548)

Cargo.toml

@@ -1,7 +1,9 @@
 [workspace]
+resolver = "2"
 members = [
   "metrics",
   "metrics-benchmark",
+  "metrics-exporter-dogstatsd",
   "metrics-exporter-prometheus",
   "metrics-exporter-tcp",
   "metrics-observer",
@@ -24,7 +26,6 @@ crossbeam-utils = { version = "0.8", default-features = false }
 getopts = { version = "0.2", default-features = false }
 hashbrown = { version = "0.15", default-features = false, features = ["default-hasher", "raw-entry"] }
 hdrhistogram = { version = "7.2", default-features = false }
-home = { version = "0.5", default-features = false }
 http-body-util = { version = "0.1", default-features = false }
 hyper = { version = "1.1", default-features = false, features = ["server", "client"] }
 hyper-rustls = { version = "0.27", default-features = false, features = ["aws-lc-rs", "http1", "rustls-native-certs"] }

clippy.toml

@@ -1,2 +1,3 @@
 too-many-lines-threshold = 150
 ignore-interior-mutability = ["metrics::key::Key"]
+doc-valid-idents = ["DogStatsD", ".."]

metrics-exporter-dogstatsd/CHANGELOG.md

@@ -0,0 +1,13 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+<!-- next-header -->
+
+## [Unreleased] - ReleaseDate
+
+### Added
+
+- Genesis.

metrics-exporter-dogstatsd/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "metrics-exporter-dogstatsd"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+bytes = { version = "1", default-features = false }
+ryu = { version = "1", default-features = false }
+itoa = { version = "1", default-features = false }
+metrics = { version = "^0.24", path = "../metrics" }
+metrics-util = { version = "^0.18", path = "../metrics-util" }
+thiserror = { workspace = true }
+tracing = { workspace = true }
+
+[dev-dependencies]
+proptest = { workspace = true }
+rand = { workspace = true }
+rand_xoshiro = { version = "0.6", default-features = false }
+tracing = { workspace = true }
+tracing-subscriber = { workspace = true, features = ["fmt"] }

metrics-exporter-dogstatsd/examples/dogstatsd_idle_counter.rs

@@ -0,0 +1,28 @@
+use std::time::{Duration, Instant};
+
+use metrics::counter;
+use metrics_exporter_dogstatsd::DogStatsDBuilder;
+
+fn main() {
+    tracing_subscriber::fmt::init();
+
+    DogStatsDBuilder::default()
+        .with_remote_address("localhost:9125")
+        .expect("failed to parse remote address")
+        .with_telemetry(false)
+        .install()
+        .expect("failed to install DogStatsD recorder");
+
+    counter!("idle_metric").increment(1);
+
+    // Loop over and over, incrementing our counter every 10 seconds or so.
+    let mut last_update = Instant::now();
+    loop {
+        if last_update.elapsed() > Duration::from_secs(10) {
+            counter!("idle_metric").increment(1);
+            last_update = Instant::now();
+        }
+
+        std::thread::sleep(Duration::from_secs(1));
+    }
+}

metrics-exporter-dogstatsd/examples/dogstatsd_synchronous.rs

@@ -0,0 +1,36 @@
+use metrics::{counter, gauge, histogram};
+use metrics_exporter_dogstatsd::DogStatsDBuilder;
+use rand::{thread_rng, Rng, SeedableRng as _};
+use rand_xoshiro::Xoshiro256StarStar;
+
+fn main() {
+    tracing_subscriber::fmt::init();
+
+    DogStatsDBuilder::default()
+        .with_remote_address("localhost:9125")
+        .expect("failed to parse remote address")
+        .install()
+        .expect("failed to install DogStatsD recorder");
+
+    counter!("idle_metric").increment(1);
+    gauge!("testing").set(42.0);
+
+    let server_loops = counter!("tcp_server_loops", "system" => "foo");
+    let server_loops_delta_secs = histogram!("tcp_server_loop_delta_secs", "system" => "foo");
+
+    let mut rng = Xoshiro256StarStar::from_rng(thread_rng()).unwrap();
+
+    // Loop over and over, pretending to do some work.
+    loop {
+        server_loops.increment(1);
+        server_loops_delta_secs.record(rng.gen_range(0.0..1.0));
+
+        let increment_gauge = thread_rng().gen_bool(0.75);
+        let gauge = gauge!("lucky_iterations");
+        if increment_gauge {
+            gauge.increment(1.0);
+        } else {
+            gauge.decrement(1.0);
+        }
+    }
+}

metrics-exporter-dogstatsd/proptest-regressions/forwarder/writer.txt

@@ -0,0 +1,7 @@
+# Seeds for failure cases proptest has generated in the past. It is
+# automatically read and these particular cases re-run before any
+# novel cases are generated.
+#
+# It is recommended to check this file in to source control so that
+# everyone who runs the test benefits from these saved cases.
+cc 996294ee8ec0a637930c95346f0165bbaba2cbf701d321de8d713d7f723f0ff0 # shrinks to payload_limit = 43, inputs = [Histogram(Key { name: KeyName("A0AA0A0A"), labels: [], hashed: true, hash: 18423047812237334005 }, [-0.0, 3.1748022040256364e164], 10000000)]