ref(iroh-metrics, iroh-relay): Remove the UsageStatsReporter (#2952)

## Description

This was unused and a rather scary footgun that could easily lead to
way to many http requests being made.

## Breaking Changes

<!-- Optional, if there are any breaking changes document them,
including how to migrate older code. -->

## Notes & open questions

<!-- Any notes, remarks or open questions you have to make about the PR.
-->

## Change checklist

- [x] Self-review.
- [x] Documentation updates following the [style
guide](https://rust-lang.github.io/rfcs/1574-more-api-documentation-conventions.html#appendix-a-full-conventions-text),
if relevant.
- [x] Tests if relevant.
- [x] All breaking changes documented.

iroh-metrics/src/core.rs

@@ -1,26 +1,21 @@
-use anyhow::Error;
 use erased_set::ErasedSyncSet;
 use once_cell::sync::OnceCell;
 #[cfg(feature = "metrics")]
 use prometheus_client::{encoding::text::encode, registry::Registry};
-use serde::{Deserialize, Serialize};
-use time::OffsetDateTime;
-use tracing::trace;
 #[cfg(not(feature = "metrics"))]
 type Registry = ();
 
 static CORE: OnceCell<Core> = OnceCell::new();
 
 /// Core is the base metrics struct.
+///
 /// It manages the mapping between the metrics name and the actual metrics.
 /// It also carries a single prometheus registry to be used by all metrics.
 #[derive(Debug, Default)]
 pub struct Core {
     #[cfg(feature = "metrics")]
     registry: Registry,
     metrics_map: ErasedSyncSet,
-    #[cfg(feature = "metrics")]
-    usage_reporter: UsageReporter,
 }
 /// Open Metrics [`Counter`] to measure discrete events.
 ///
@@ -154,15 +149,10 @@ impl Core {
         let mut metrics_map = ErasedSyncSet::new();
         f(&mut registry, &mut metrics_map);
 
-        #[cfg(feature = "metrics")]
-        let usage_reporter = UsageReporter::new();
-
         CORE.set(Core {
             metrics_map,
             #[cfg(feature = "metrics")]
             registry,
-            #[cfg(feature = "metrics")]
-            usage_reporter,
         })
         .map_err(|_| std::io::Error::new(std::io::ErrorKind::Other, "already set"))
     }
@@ -191,11 +181,6 @@ impl Core {
         encode(&mut buf, &self.registry)?;
         Ok(buf)
     }
-
-    #[cfg(feature = "metrics")]
-    pub(crate) fn usage_reporter(&self) -> &UsageReporter {
-        &self.usage_reporter
-    }
 }
 
 /// Interface for all single value based metrics.
@@ -209,83 +194,3 @@ pub trait HistogramType {
     /// Returns the name of the metric
     fn name(&self) -> &'static str;
 }
-
-/// Exposes a simple API to report usage statistics.
-#[derive(Debug, Default)]
-pub struct UsageReporter {
-    pub(crate) report_endpoint: Option<String>,
-    pub(crate) report_token: Option<String>,
-}
-
-impl UsageReporter {
-    /// Creates a new usage reporter.
-    pub fn new() -> Self {
-        let report_endpoint = std::env::var("IROH_METRICS_USAGE_STATS_ENDPOINT").ok();
-        let report_token = std::env::var("IROH_METRICS_USAGE_STATS_TOKEN").ok();
-        UsageReporter {
-            report_endpoint,
-            report_token,
-        }
-    }
-
-    /// Reports usage statistics to the configured endpoint.
-    pub async fn report_usage_stats(&self, report: &UsageStatsReport) -> Result<(), Error> {
-        if let Some(report_endpoint) = &self.report_endpoint {
-            trace!("reporting usage stats to {}", report_endpoint);
-            let mut client = reqwest::Client::new().post(report_endpoint);
-
-            if let Some(report_token) = &self.report_token {
-                let mut headers = reqwest::header::HeaderMap::new();
-                headers.insert(
-                    reqwest::header::COOKIE,
-                    format!("token={}", report_token).parse().unwrap(),
-                );
-                client = client.headers(headers);
-            }
-            let _ = client.json(report).send().await?;
-        }
-        Ok(())
-    }
-}
-
-/// Usage statistics report.
-#[derive(Clone, Debug, Serialize, Deserialize)]
-pub struct UsageStatsReport {
-    /// The timestamp of the report.
-    #[serde(with = "time::serde::rfc3339")]
-    pub timestamp: OffsetDateTime,
-    /// The resource being consumed.
-    pub resource: String,
-    /// Reference to the resource reporter.
-    pub resource_ref: String,
-    /// The value of the resource being consumed.
-    pub value: i64,
-    /// Identifier of the user consuming the resource.
-    pub attribution_id: Option<String>,
-    /// Public key of the user consuming the resource.
-    pub attribution_key: Option<String>,
-}
-
-/// Type alias for a metered resource.
-pub type UsageResource = String;
-
-impl UsageStatsReport {
-    /// Creates a new usage stats report.
-    pub fn new(
-        resource: UsageResource,
-        resource_ref: String,
-        value: i64,
-        attribution_id: Option<String>,
-        attribution_key: Option<String>,
-    ) -> Self {
-        let timestamp = OffsetDateTime::now_utc();
-        UsageStatsReport {
-            timestamp,
-            resource,
-            resource_ref,
-            value,
-            attribution_id,
-            attribution_key,
-        }
-    }
-}

iroh-metrics/src/lib.rs

@@ -10,7 +10,6 @@ pub mod core;
 #[cfg(feature = "metrics")]
 mod service;
 
-use core::UsageStatsReport;
 use std::collections::HashMap;
 
 /// Reexport to make matching versions easier.
@@ -40,22 +39,6 @@ macro_rules! set {
     };
 }
 
-/// Report usage statistics to the configured endpoint.
-#[allow(unused_variables)]
-pub async fn report_usage_stats(report: &UsageStatsReport) {
-    #[cfg(feature = "metrics")]
-    {
-        if let Some(core) = core::Core::get() {
-            core.usage_reporter()
-                .report_usage_stats(report)
-                .await
-                .unwrap_or_else(|e| {
-                    tracing::error!("Failed to report usage stats: {}", e);
-                });
-        }
-    }
-}
-
 /// Parse Prometheus metrics from a string.
 pub fn parse_prometheus_metrics(data: &str) -> anyhow::Result<HashMap<String, f64>> {
     let mut metrics = HashMap::new();

iroh-relay/src/server/actor.rs

@@ -7,9 +7,9 @@ use std::{collections::HashMap, time::Duration};
 use anyhow::{bail, Result};
 use bytes::Bytes;
 use iroh_base::key::NodeId;
-use iroh_metrics::{core::UsageStatsReport, inc, inc_by, report_usage_stats};
+use iroh_metrics::{inc, inc_by};
 use time::{Date, OffsetDateTime};
-use tokio::{sync::mpsc, task::JoinSet};
+use tokio::sync::mpsc;
 use tokio_util::{sync::CancellationToken, task::AbortOnDropHandle};
 use tracing::{info, info_span, trace, warn, Instrument};
 
@@ -114,7 +114,6 @@ impl Actor {
     }
 
     async fn run(mut self, done: CancellationToken) -> Result<()> {
-        let mut tasks = JoinSet::new();
         loop {
             tokio::select! {
                 biased;
@@ -126,16 +125,9 @@ impl Actor {
                     self.clients.shutdown().await;
                     return Ok(());
                 }
-                Some(res) = tasks.join_next(), if !tasks.is_empty() => {
-                    if let Err(err) = res {
-                        if err.is_panic() {
-                            panic!("Task panicked: {err:?}");
-                        }
-                    }
-                }
                 msg = self.receiver.recv() => match msg {
                     Some(msg) => {
-                        self.handle_message(msg, &mut tasks).await;
+                        self.handle_message(msg).await;
                     }
                     None => {
                         warn!("unexpected actor error: receiver gone, shutting down actor loop");
@@ -147,7 +139,7 @@ impl Actor {
         }
     }
 
-    async fn handle_message(&mut self, msg: Message, tasks: &mut JoinSet<()>) {
+    async fn handle_message(&mut self, msg: Message) {
         match msg {
             Message::SendPacket { dst, data, src } => {
                 trace!(?src, ?dst, len = data.len(), "send packet");
@@ -198,18 +190,9 @@ impl Actor {
                 );
                 let node_id = client_builder.node_id;
 
-                // build and register client, starting up read & write loops for the client connection
+                // build and register client, starting up read & write loops for the client
+                // connection
                 self.clients.register(client_builder).await;
-                tasks.spawn(async move {
-                    report_usage_stats(&UsageStatsReport::new(
-                        "relay_accepts".to_string(),
-                        "relay_server".to_string(), // TODO: other id?
-                        1,
-                        None, // TODO(arqu): attribute to user id; possibly with the re-introduction of request tokens or other auth
-                        Some(node_id.to_string()),
-                    ))
-                    .await;
-                });
                 let nc = self.client_counter.update(node_id);
                 inc_by!(Metrics, unique_client_keys, nc);
             }