warn if no max_head_block_age

config/development_polygon.toml

@@ -23,6 +23,8 @@ min_sum_soft_limit = 1_000
 # only mark a block as the head block if the number of servers with it is great than or equal to min_synced_rpcs
 min_synced_rpcs = 1
 
+max_head_block_age = 30
+
 # redis is optional. it is used for rate limits set by `hard_limit`
 # TODO: how do we find the optimal redis_max_connections? too high actually ends up being slower
 volatile_redis_max_connections = 20

config/example.toml

@@ -28,6 +28,9 @@ min_sum_soft_limit = 2_000
 # only mark a block as the head block if the number of servers with it is great than or equal to min_synced_rpcs
 min_synced_rpcs = 2
 
+# don't serve requests if the best known block is >60 seconds old
+max_head_block_age = 60
+
 # redis is optional. it is used for rate limits set by `hard_limit`
 # TODO: how do we find the optimal redis_max_connections? too high actually ends up being slower
 volatile_redis_max_connections = 300

web3_proxy/src/app/mod.rs

@@ -196,6 +196,10 @@ impl Web3ProxyApp {
             );
         }
 
+        if top_config.app.max_head_block_age.is_none() {
+            warn!("no max_head_block_age. stale data could be served!");
+        }
+
         if !top_config.extra.is_empty() {
             warn!(
                 "unknown TopConfig fields!: {:?}",
@@ -501,7 +505,7 @@ impl Web3ProxyApp {
 
         let (balanced_rpcs, balanced_handle, consensus_connections_watcher) = Web3Rpcs::spawn(
             db_conn.clone(),
-            top_config.app.max_block_age,
+            top_config.app.max_head_block_age,
             top_config.app.max_block_lag,
             top_config.app.min_synced_rpcs,
             top_config.app.min_sum_soft_limit,
@@ -526,7 +530,7 @@ impl Web3ProxyApp {
             // let (private_rpcs, private_rpcs_handle) = Web3Rpcs::spawn(
             let (private_rpcs, private_handle, _) = Web3Rpcs::spawn(
                 db_conn.clone(),
-                // private rpcs don't get subscriptions, so no need for max_block_age or max_block_lag
+                // private rpcs don't get subscriptions, so no need for max_head_block_age or max_block_lag
                 None,
                 None,
                 0,
@@ -558,7 +562,7 @@ impl Web3ProxyApp {
             // TODO: do something with the spawn handle
             let (bundler_4337_rpcs, bundler_4337_rpcs_handle, _) = Web3Rpcs::spawn(
                 db_conn.clone(),
-                // bundler_4337_rpcs don't get subscriptions, so no need for max_block_age or max_block_lag
+                // bundler_4337_rpcs don't get subscriptions, so no need for max_head_block_age or max_block_lag
                 None,
                 None,
                 0,

web3_proxy/src/config.rs

@@ -121,7 +121,7 @@ pub struct AppConfig {
     pub login_domain: Option<String>,
 
     /// do not serve any requests if the best known block is older than this many seconds.
-    pub max_block_age: Option<u64>,
+    pub max_head_block_age: Option<u64>,
 
     /// do not serve any requests if the best known block is behind the best known block by more than this many blocks.
     pub max_block_lag: Option<U64>,

web3_proxy/src/rpcs/blockchain.rs

@@ -401,7 +401,8 @@ impl Web3Rpcs {
         // Geth's subscriptions have the same potential for skipping blocks.
         pending_tx_sender: Option<broadcast::Sender<TxStatus>>,
     ) -> Web3ProxyResult<()> {
-        let mut connection_heads = ConsensusFinder::new(self.max_block_age, self.max_block_lag);
+        let mut connection_heads =
+            ConsensusFinder::new(self.max_head_block_age, self.max_block_lag);
 
         loop {
             match block_receiver.recv_async().await {

web3_proxy/src/rpcs/consensus.rs

@@ -339,7 +339,7 @@ type FirstSeenCache = Cache<H256, Instant>;
 pub struct ConsensusFinder {
     rpc_heads: HashMap<Arc<Web3Rpc>, Web3ProxyBlock>,
     /// never serve blocks that are too old
-    max_block_age: Option<u64>,
+    max_head_block_age: Option<u64>,
     /// tier 0 will be prefered as long as the distance between it and the other tiers is <= max_tier_lag
     max_block_lag: Option<U64>,
     /// Block Hash -> First Seen Instant. used to track rpc.head_latency. The same cache should be shared between all ConnectionsGroups
@@ -347,7 +347,7 @@ pub struct ConsensusFinder {
 }
 
 impl ConsensusFinder {
-    pub fn new(max_block_age: Option<u64>, max_block_lag: Option<U64>) -> Self {
+    pub fn new(max_head_block_age: Option<u64>, max_block_lag: Option<U64>) -> Self {
         // TODO: what's a good capacity for this? it shouldn't need to be very large
         let first_seen = Cache::new(16);
 
@@ -355,7 +355,7 @@ impl ConsensusFinder {
 
         Self {
             rpc_heads,
-            max_block_age,
+            max_head_block_age,
             max_block_lag,
             first_seen,
         }
@@ -406,7 +406,7 @@ impl ConsensusFinder {
                     .await
                     .web3_context("failed caching block")?;
 
-                if let Some(max_age) = self.max_block_age {
+                if let Some(max_age) = self.max_head_block_age {
                     if rpc_head_block.age() > max_age {
                         trace!("rpc_head_block from {} is too old! {}", rpc, rpc_head_block);
                         return Ok(self.remove(&rpc).is_some());
@@ -536,6 +536,7 @@ impl ConsensusFinder {
 
         trace!("lowest_block_number: {}", lowest_block.number());
 
+        // TODO: move this default. should be in config, not here
         let max_lag_block_number =
             highest_block_number.saturating_sub(self.max_block_lag.unwrap_or_else(|| U64::from(5)));
 

web3_proxy/src/rpcs/many.rs

@@ -68,7 +68,7 @@ pub struct Web3Rpcs {
     /// how far behind the highest known block height we can be before we stop serving requests
     pub(super) max_block_lag: Option<U64>,
     /// how old our consensus head block we can be before we stop serving requests
-    pub(super) max_block_age: Option<u64>,
+    pub(super) max_head_block_age: Option<u64>,
 }
 
 impl Web3Rpcs {
@@ -76,7 +76,7 @@ impl Web3Rpcs {
     #[allow(clippy::too_many_arguments)]
     pub async fn spawn(
         db_conn: Option<DatabaseConnection>,
-        max_block_age: Option<u64>,
+        max_head_block_age: Option<u64>,
         max_block_lag: Option<U64>,
         min_head_rpcs: usize,
         min_sum_soft_limit: u32,
@@ -120,7 +120,7 @@ impl Web3Rpcs {
             blocks_by_hash,
             blocks_by_number,
             by_name,
-            max_block_age,
+            max_head_block_age,
             max_block_lag,
             min_synced_rpcs: min_head_rpcs,
             min_sum_soft_limit,
@@ -1526,8 +1526,8 @@ mod tests {
             blocks_by_number: CacheBuilder::new(100)
                 .time_to_live(Duration::from_secs(60))
                 .build(),
-            // TODO: test max_block_age?
+            // TODO: test max_head_block_age?
-            max_block_age: None,
+            max_head_block_age: None,
             // TODO: test max_block_lag?
             max_block_lag: None,
             min_synced_rpcs: 1,
@@ -1808,7 +1808,7 @@ mod tests {
                 .build(),
             min_synced_rpcs: 1,
             min_sum_soft_limit: 4_000,
-            max_block_age: None,
+            max_head_block_age: None,
             max_block_lag: None,
         };
 
@@ -1988,7 +1988,7 @@ mod tests {
             blocks_by_number: Cache::new(10_000),
             min_synced_rpcs: 1,
             min_sum_soft_limit: 1_000,
-            max_block_age: None,
+            max_head_block_age: None,
             max_block_lag: None,
         };