address feedback: emit event per block instead of per epoch

crates/core/component/distributions/src/component.rs

@@ -41,11 +41,36 @@ impl Component for Distributions {
     ) {
     }
 
-    #[instrument(name = "distributions", skip(_state, _end_block))]
+    #[instrument(name = "distributions", skip(state))]
     async fn end_block<S: StateWrite + 'static>(
-        _state: &mut Arc<S>,
-        _end_block: &abci::request::EndBlock,
+        state: &mut Arc<S>,
+        end_block: &abci::request::EndBlock,
     ) {
+        let state = Arc::get_mut(state).expect("the state should not be shared");
+
+        let current_epoch = state.get_current_epoch().await.expect("msg");
+        let current_block_height = end_block
+            .height
+            .try_into()
+            .expect("block height should not be negative");
+
+        let new_issuance = state
+            .get_distributions_params()
+            .await
+            .expect("distribution parameters should be available")
+            .staking_issuance_per_block as u128;
+
+        let total_new_issuance = state
+            .compute_lqt_issuance_from_blocks(current_epoch, current_block_height)
+            .await
+            .expect("should be able to compute LQT issuance from block");
+
+        // Emit an event for LQT pool size increase at the end of the block.
+        state.record_proto(event::event_lqt_pool_size_increase(
+            current_epoch.index,
+            new_issuance.into(),
+            total_new_issuance,
+        ))
     }
 
     #[instrument(name = "distributions", skip(state))]
@@ -109,9 +134,12 @@ trait DistributionManager: StateWriteExt {
         Ok(self.set_staking_token_issuance_for_epoch(new_issuance))
     }
 
-    /// Computes total LQT reward issuance for the epoch.
-    async fn compute_new_lqt_issuance(&self, current_epoch: Epoch) -> Result<Amount> {
-        let current_block_height = self.get_block_height().await?;
+    /// Helper function that computes the LQT issuance for the current block height in the epoch.
+    async fn compute_lqt_issuance_from_blocks(
+        &self,
+        current_epoch: Epoch,
+        current_block_height: u64,
+    ) -> Result<Amount> {
         let epoch_length = current_block_height
             .checked_sub(current_epoch.start_height)
             .unwrap_or_else(|| panic!("epoch start height is greater than current block height (epoch_start={}, current_height={}", current_epoch.start_height, current_block_height));
@@ -139,6 +167,15 @@ trait DistributionManager: StateWriteExt {
         Ok(Amount::from(total_pool_size_for_epoch))
     }
 
+    /// Computes total LQT reward issuance for the epoch.
+    async fn compute_new_lqt_issuance(&self, current_epoch: Epoch) -> Result<Amount> {
+        let current_block_height = self.get_block_height().await?;
+
+        Ok(self
+            .compute_lqt_issuance_from_blocks(current_epoch, current_block_height)
+            .await?)
+    }
+
     /// Update the nonverifiable storage with the newly issued LQT rewards for the current epoch.
     async fn define_lqt_budget(&mut self) -> Result<()> {
         // Grab the ambient epoch index.
@@ -152,31 +189,7 @@ trait DistributionManager: StateWriteExt {
             current_epoch.index
         );
 
-        // Retrieve the previous cumulative LQT issuance total from NV storage.
-        let previous_issuance = self
-            .get_cummulative_lqt_reward_issuance(current_epoch.index - 1)
-            .await
-            .ok_or_else(|| {
-                tonic::Status::not_found(format!(
-                    "failed to retrieve cumulative LQT issuance for epoch {} from non-verifiable storage",
-                    current_epoch.index,
-                ))
-            })?;
-
-        // Compute cumulative LQT issuance up until current epoch.
-        let cumulative_issuance = previous_issuance + new_issuance;
-
-        // Emit an event for LQT pool size increase.
-        self.record_proto(event::event_lqt_pool_size_increase(
-            current_epoch.index,
-            new_issuance,
-            cumulative_issuance,
-        ));
-
-        self.set_lqt_reward_issuance_for_epoch(current_epoch.index, new_issuance);
-        self.set_cumulative_lqt_reward_issuance(current_epoch.index, cumulative_issuance);
-
-        Ok(())
+        Ok(self.set_lqt_reward_issuance_for_epoch(current_epoch.index, new_issuance))
     }
 }
 

crates/core/component/distributions/src/component/state_key.rs

@@ -17,14 +17,6 @@ pub mod lqt {
                 key[0..48].copy_from_slice(prefix_bytes.as_bytes());
                 key
             }
-
-            /// The amount of LQT rewards issued up until this epoch.
-            pub fn cumulative(epoch_index: u64) -> [u8; 59] {
-                let key_str = format!("distributions/lqt/v1/budget/cumulative/{epoch_index:020}");
-                let mut key = [0u8; 59];
-                key.copy_from_slice(key_str.as_bytes());
-                key
-            }
         }
     }
 }

crates/core/component/distributions/src/component/view.rs

@@ -29,16 +29,6 @@ pub trait StateReadExt: StateRead {
             None
         })
     }
-
-    // Get the cumulative amount of LQT rewards issued up until this epoch.
-    async fn get_cummulative_lqt_reward_issuance(&self, epoch_index: u64) -> Option<Amount> {
-        let key = state_key::lqt::v1::budget::cumulative(epoch_index);
-
-        self.nonverifiable_get(&key).await.unwrap_or_else(|_| {
-            tracing::error!("cumulative LQT issuance does not exist for epoch");
-            None
-        })
-    }
 }
 
 impl<T: StateRead + ?Sized> StateReadExt for T {}
@@ -62,13 +52,5 @@ pub trait StateWriteExt: StateWrite + StateReadExt {
             issuance,
         );
     }
-
-    /// Set the cumulative amount of LQT rewards issued up until this epoch.
-    fn set_cumulative_lqt_reward_issuance(&mut self, epoch_index: u64, issuance: Amount) {
-        self.nonverifiable_put(
-            state_key::lqt::v1::budget::cumulative(epoch_index).into(),
-            issuance,
-        );
-    }
 }
 impl<T: StateWrite + ?Sized> StateWriteExt for T {}