From e8977d203be1f2789b67ae0dcbf2b90e865b0c9d Mon Sep 17 00:00:00 2001
From: Bryan Stitt <bryan@satoshiandkin.com>
Date: Tue, 6 Sep 2022 03:26:23 +0000
Subject: [PATCH] use None more

---
 web3_proxy/src/rpcs/connection.rs | 35 ++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/web3_proxy/src/rpcs/connection.rs b/web3_proxy/src/rpcs/connection.rs
index f33741dc..24c2e724 100644
--- a/web3_proxy/src/rpcs/connection.rs
+++ b/web3_proxy/src/rpcs/connection.rs
@@ -40,7 +40,7 @@ pub struct Web3Connection {
     /// Lower weight are higher priority when sending requests
     pub(super) weight: u32,
     // TODO: async lock?
-    pub(super) head_block_id: RwLock<BlockId>,
+    pub(super) head_block_id: RwLock<Option<BlockId>>,
 }
 
 impl Web3Connection {
@@ -162,23 +162,27 @@ impl Web3Connection {
         let mut limit = None;
 
         for block_data_limit in [u64::MAX, 90_000, 128, 64, 32] {
-            let mut head_block_num = self.head_block_id.read().num;
+            let mut head_block_id = self.head_block_id.read().clone();
 
             // TODO: wait until head block is set outside the loop? if we disconnect while starting we could actually get 0 though
-            while head_block_num == U64::zero() {
+            while head_block_id.is_none() {
                 warn!(rpc=%self, "no head block yet. retrying");
 
                 // TODO: subscribe to a channel instead of polling? subscribe to http_interval_sender?
                 sleep(Duration::from_secs(1)).await;
 
-                head_block_num = self.head_block_id.read().num;
+                head_block_id = self.head_block_id.read().clone();
             }
+            let head_block_num = head_block_id.expect("is_none was checked above").num;
+
+            debug_assert_ne!(head_block_num, U64::zero());
 
             // TODO: subtract 1 from block_data_limit for safety?
             let maybe_archive_block = head_block_num
                 .saturating_sub((block_data_limit).into())
                 .max(U64::one());
 
+            // TODO: wait for the handle BEFORE we check the current block number. it might be delayed too!
             let archive_result: Result<Bytes, _> = self
                 .wait_for_request_handle()
                 .await?
@@ -216,7 +220,12 @@ impl Web3Connection {
     pub fn has_block_data(&self, needed_block_num: &U64) -> bool {
         let block_data_limit: U64 = self.block_data_limit();
 
-        let newest_block_num = self.head_block_id.read().num;
+        let head_block_id = self.head_block_id.read().clone();
+
+        let newest_block_num = match head_block_id {
+            None => return false,
+            Some(x) => x.num,
+        };
 
         let oldest_block_num = newest_block_num
             .saturating_sub(block_data_limit)
@@ -322,10 +331,20 @@ impl Web3Connection {
                 // save the block so we don't send the same one multiple times
                 // also save so that archive checks can know how far back to query
                 {
-                    let mut head_block = self.head_block_id.write();
+                    let mut head_block_id = self.head_block_id.write();
 
-                    head_block.hash = new_hash;
-                    head_block.num = new_num;
+                    if head_block_id.is_none() {
+                        *head_block_id = Some(BlockId {
+                            hash: new_hash,
+                            num: new_num,
+                        });
+                    } else {
+                        head_block_id.as_mut().map(|x| {
+                            x.hash = new_hash;
+                            x.num = new_num;
+                            x
+                        });
+                    }
                 }
 
                 block_sender