feat: add state transition counter metrics

crates/blockchain/state_transition/Cargo.toml

@@ -13,6 +13,7 @@ version.workspace = true
 ethlambda-types.workspace = true
 
 thiserror.workspace = true
+prometheus.workspace = true
 
 [dev-dependencies]
 serde.workspace = true

crates/blockchain/state_transition/src/lib.rs

@@ -7,6 +7,7 @@ use ethlambda_types::{
 };
 
 mod justified_slots_ops;
+pub mod metrics;
 
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
@@ -65,7 +66,9 @@ pub fn process_slots(state: &mut State, target_slot: u64) -> Result<(), Error> {
         // Special case: cache the state root if not already set.
         state.latest_block_header.state_root = state.tree_hash_root();
     }
+    let slots_processed = target_slot - state.slot;
     state.slot = target_slot;
+    metrics::inc_slots_processed(slots_processed);
     Ok(())
 }
 
@@ -182,6 +185,7 @@ fn process_attestations(
     attestations: &AggregatedAttestations,
 ) -> Result<(), Error> {
     let validator_count = state.validators.len();
+    let mut attestations_processed: u64 = 0;
     let mut justifications: HashMap<H256, Vec<bool>> = state
         .justifications_roots
         .iter()
@@ -259,6 +263,7 @@ fn process_attestations(
         }
 
         // Record the vote
+        attestations_processed += 1;
         let votes = justifications
             .entry(target.root)
             .or_insert_with(|| std::iter::repeat_n(false, validator_count).collect());
@@ -292,6 +297,7 @@ fn process_attestations(
             {
                 let old_finalized_slot = state.latest_finalized.slot;
                 state.latest_finalized = source;
+                metrics::inc_finalizations("success");
 
                 // Shift window to drop finalized slots from the front
                 let delta = (state.latest_finalized.slot - old_finalized_slot) as usize;
@@ -331,6 +337,7 @@ fn process_attestations(
         .try_into()
         .expect("justifications_roots limit exceeded");
     state.justifications_validators = justifications_validators;
+    metrics::inc_attestations_processed(attestations_processed);
     Ok(())
 }
 

crates/blockchain/state_transition/src/metrics.rs

@@ -0,0 +1,46 @@
+//! Prometheus metrics for state transition.
+
+use std::sync::LazyLock;
+
+use prometheus::{IntCounter, IntCounterVec, register_int_counter, register_int_counter_vec};
+
+static LEAN_STATE_TRANSITION_SLOTS_PROCESSED_TOTAL: LazyLock<IntCounter> = LazyLock::new(|| {
+    register_int_counter!(
+        "lean_state_transition_slots_processed_total",
+        "Count of processed slots"
+    )
+    .unwrap()
+});
+
+static LEAN_STATE_TRANSITION_ATTESTATIONS_PROCESSED_TOTAL: LazyLock<IntCounter> =
+    LazyLock::new(|| {
+        register_int_counter!(
+            "lean_state_transition_attestations_processed_total",
+            "Count of processed attestations"
+        )
+        .unwrap()
+    });
+
+static LEAN_FINALIZATIONS_TOTAL: LazyLock<IntCounterVec> = LazyLock::new(|| {
+    register_int_counter_vec!(
+        "lean_finalizations_total",
+        "Total number of finalization attempts",
+        &["result"]
+    )
+    .unwrap()
+});
+
+/// Increment the slots processed counter by the given amount.
+pub fn inc_slots_processed(count: u64) {
+    LEAN_STATE_TRANSITION_SLOTS_PROCESSED_TOTAL.inc_by(count);
+}
+
+/// Increment the attestations processed counter by the given amount.
+pub fn inc_attestations_processed(count: u64) {
+    LEAN_STATE_TRANSITION_ATTESTATIONS_PROCESSED_TOTAL.inc_by(count);
+}
+
+/// Increment the finalization counter with the given result.
+pub fn inc_finalizations(result: &str) {
+    LEAN_FINALIZATIONS_TOTAL.with_label_values(&[result]).inc();
+}

docs/metrics.md

@@ -47,12 +47,12 @@ The exposed metrics follow [the leanMetrics specification](https://github.com/le
 |--------|-------|-------|-------------------------|--------|---------|-----------|
 | `lean_latest_justified_slot` | Gauge | Latest justified slot | On state transition | | | ✅ |
 | `lean_latest_finalized_slot` | Gauge | Latest finalized slot | On state transition | | | ✅ |
-| `lean_finalizations_total` | Counter | Total number of finalization attempts | On finalization attempt | result=success,error | | □ |
+| `lean_finalizations_total` | Counter | Total number of finalization attempts | On finalization attempt | result=success,error | | ✅ |
 |`lean_state_transition_time_seconds`| Histogram | Time to process state transition | On state transition | | 0.25, 0.5, 0.75, 1, 1.25, 1.5, 2, 2.5, 3, 4 | □ |
-|`lean_state_transition_slots_processed_total`| Counter | Total number of processed slots | On state transition process slots | | | □ |
+|`lean_state_transition_slots_processed_total`| Counter | Total number of processed slots | On state transition process slots | | | ✅ |
 |`lean_state_transition_slots_processing_time_seconds`| Histogram | Time taken to process slots | On state transition process slots | | 0.005, 0.01, 0.025, 0.05, 0.1, 1 | □ |
 |`lean_state_transition_block_processing_time_seconds`| Histogram | Time taken to process block | On state transition process block | | 0.005, 0.01, 0.025, 0.05, 0.1, 1 | □ |
-|`lean_state_transition_attestations_processed_total`| Counter | Total number of processed attestations | On state transition process attestations | | | □ |
+|`lean_state_transition_attestations_processed_total`| Counter | Total number of processed attestations | On state transition process attestations | | | ✅ |
 |`lean_state_transition_attestations_processing_time_seconds`| Histogram | Time taken to process attestations | On state transition process attestations | | 0.005, 0.01, 0.025, 0.05, 0.1, 1 | □ |
 
 ## Validator Metrics