feat: add logging for RPC subscription notifications

[pedro-pelicioni-cw]

User description

Add detailed tracing logs for RPC subscription events, including:

• Pending transaction notifications
• New block header notifications
• Log event notifications

The logs now include relevant context such as transaction hash, block number, and the number of subscribers being notified.

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PR Type

Enhancement

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Description

• Add detailed tracing logs for RPC subscription events

• Log pending transactions, new block headers, log events

• Include context: transaction hash, block number, subscribers count

• Improve visibility and debugging for subscription notifications

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Changes walkthrough 📝

	Relevant files
Enhancement	rpc_subscriptions.rs Add tracing logs for RPC subscription events                          src/eth/rpc/rpc_subscriptions.rs Add tracing::info! logs for pending transactions Implement logging for new block header notifications Include logging for log event notifications Log relevant context: tx hash, block number, subscribers count +22/-0

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[github-actions]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Logging Consistency Ensure that the logging format and level are consistent across all three notification types (pending transactions, new blocks, and logs). Consider standardizing the field names and log levels for better consistency and easier log parsing. tracing::info!( tx_hash = ?tx_hash, subscribers_count = interested_subs.len(), "notifying subscribers about new pending transaction" ); Self::notify(interested_subs, tx_hash.to_string()); } warn_task_rx_closed(TASK_NAME); Ok(()) }) } /// Spawns a new task that notifies subscribers about new created blocks. fn spawn_new_heads_notifier(subs: Arc<RpcSubscriptionsConnected>, mut rx_block: broadcast::Receiver<BlockHeader>) -> JoinHandle<anyhow::Result<()>> { const TASK_NAME: &str = "rpc::sub::newHeads"; spawn_named(TASK_NAME, async move { loop { if GlobalState::is_shutdown_warn(TASK_NAME) { return Ok(()); } let block_header = match timeout(NOTIFIER_SHUTDOWN_CHECK_INTERVAL, rx_block.recv()).await { Ok(Ok(block)) => block, Ok(Err(_channel_closed)) => break, Err(_timed_out) => continue, }; let interested_subs = subs.new_heads.read().await; let interested_subs = interested_subs.values().collect_vec(); tracing::info!( block_number = ?block_header.number, block_hash = ?block_header.hash, subscribers_count = interested_subs.len(), "notifying subscribers about new block" ); Self::notify(interested_subs, block_header); } warn_task_rx_closed(TASK_NAME); Ok(()) }) } /// Spawns a new task that notifies subscribers about new transactions logs. fn spawn_logs_notifier(subs: Arc<RpcSubscriptionsConnected>, mut rx_log_mined: broadcast::Receiver<LogMined>) -> JoinHandle<anyhow::Result<()>> { const TASK_NAME: &str = "rpc::sub::logs"; spawn_named(TASK_NAME, async move { loop { if GlobalState::is_shutdown_warn(TASK_NAME) { return Ok(()); } let log = match timeout(NOTIFIER_SHUTDOWN_CHECK_INTERVAL, rx_log_mined.recv()).await { Ok(Ok(log)) => log, Ok(Err(_channel_closed)) => break, Err(_timed_out) => continue, }; let interested_subs = subs.logs.read().await; let interested_subs = interested_subs .values() .flat_map(HashMap::values) .filter_map(|s| if_else!(s.filter.matches(&log), Some(&s.inner), None)) .collect_vec(); tracing::info!( log_block_number = ?log.block_number, log_tx_hash = ?log.transaction_hash, subscribers_count = interested_subs.len(), "notifying subscribers about new logs" );

[github-actions]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
General	Adjust log level for frequent events Consider using a more appropriate log level, such as 'debug', for high-frequency events like transaction notifications. This will prevent log spam in production environments while still providing valuable information for debugging. src/eth/rpc/rpc_subscriptions.rs [176-180] -tracing::info!( +tracing::debug!( tx_hash = ?tx_hash, subscribers_count = interested_subs.len(), "notifying subscribers about new pending transaction" ); Suggestion importance[1-10]: 7 __ Why: Changing the log level from 'info' to 'debug' for high-frequency events is a good practice. It helps prevent log spam in production while maintaining valuable debugging information, improving overall system observability.	Medium
	Optimize logging frequency for performance To improve performance, consider moving the logging statement outside the loop if the log message doesn't change frequently. This will reduce the number of log writes, especially when there are many subscribers. src/eth/rpc/rpc_subscriptions.rs [207-212] +let mut last_logged_block = None; loop { // ... existing code ... - tracing::info!( - block_number = ?block_header.number, - block_hash = ?block_header.hash, - subscribers_count = interested_subs.len(), - "notifying subscribers about new block" - ); + if last_logged_block != Some(block_header.number) { + tracing::info!( + block_number = ?block_header.number, + block_hash = ?block_header.hash, + subscribers_count = interested_subs.len(), + "notifying subscribers about new block" + ); + last_logged_block = Some(block_header.number); + } Self::notify(interested_subs, block_header); } Suggestion importance[1-10]: 5 __ Why: The suggestion to reduce logging frequency could improve performance, especially with many subscribers. However, it may slightly complicate the code and potentially miss logging some block information, which might be important for certain use cases.	Low

[gabriel-aranha-cw]

Final benchmark:
Run ID: bench-3084069339

Git Info:

• Branch: main
• Commit: 4511bde
• PR: feat: add logging for RPC subscription notifications #2021

Configuration:

• Target Account Strategy: Default

Leader Stats:
RPS Stats: Max: 2142.00, Min: 1409.00, Avg: 1988.91, StdDev: 83.08
TPS Stats: Max: 2156.00, Min: 1719.00, Avg: 1930.44, StdDev: 97.00

Follower Stats:
Imported Blocks/s: Max: 2.00, Min: 1.00, Avg: 1.34, StdDev: 0.47
Imported Transactions/s: Max: 4258.00, Min: 14.00, Avg: 2650.18, StdDev: 954.91

Plots:

• View Leader Plot
• View Follower Plot