From 5609feb3b3de876c5cc8ec4cbb904c6b460e59bc Mon Sep 17 00:00:00 2001
From: Morgan Mccauley <morgan@mccauley.co.nz>
Date: Fri, 23 Feb 2024 14:29:28 +1300
Subject: [PATCH] feat: Expose `LOGS_COUNT` metric

---
 block-streamer/src/main.rs    |  1 +
 block-streamer/src/metrics.rs | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/block-streamer/src/main.rs b/block-streamer/src/main.rs
index 04097df9e..1ca9beca8 100644
--- a/block-streamer/src/main.rs
+++ b/block-streamer/src/main.rs
@@ -16,6 +16,7 @@ mod test_utils;
 async fn main() -> anyhow::Result<()> {
     tracing_subscriber::registry()
         .with(tracing_subscriber::fmt::layer())
+        .with(metrics::LogCounter)
         .with(tracing_subscriber::EnvFilter::from_default_env())
         .init();
 
diff --git a/block-streamer/src/metrics.rs b/block-streamer/src/metrics.rs
index 9ce3729fa..0c691f17e 100644
--- a/block-streamer/src/metrics.rs
+++ b/block-streamer/src/metrics.rs
@@ -3,6 +3,8 @@ use lazy_static::lazy_static;
 use prometheus::{
     register_int_counter_vec, register_int_gauge_vec, Encoder, IntCounterVec, IntGaugeVec,
 };
+use tracing_subscriber::layer::Context;
+use tracing_subscriber::Layer;
 
 lazy_static! {
     pub static ref LAST_PROCESSED_BLOCK: IntGaugeVec = register_int_gauge_vec!(
@@ -23,6 +25,25 @@ lazy_static! {
         &["indexer"]
     )
     .unwrap();
+    pub static ref LOGS_COUNT: IntCounterVec = register_int_counter_vec!(
+        "queryapi_block_streamer_logs_count",
+        "Number of messages logged",
+        &["level"]
+    )
+    .unwrap();
+}
+
+pub struct LogCounter;
+
+impl<S> Layer<S> for LogCounter
+where
+    S: tracing::Subscriber,
+{
+    fn on_event(&self, event: &tracing::Event, _ctx: Context<S>) {
+        LOGS_COUNT
+            .with_label_values(&[event.metadata().level().as_str()])
+            .inc();
+    }
 }
 
 #[get("/metrics")]