From c57d1b44ef1b8cb903891e9783702c6682a18932 Mon Sep 17 00:00:00 2001
From: Tyera Eulberg <teulberg@gmail.com>
Date: Tue, 15 Jun 2021 17:34:07 -0600
Subject: [PATCH] Properly handle block_height in Bigtable bincode
 deserialization (#17990)

* Default block_height on eof

* Add comment to prevent future errors
---
 storage-bigtable/src/lib.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/storage-bigtable/src/lib.rs b/storage-bigtable/src/lib.rs
index 767d34684d..b78b145a2a 100644
--- a/storage-bigtable/src/lib.rs
+++ b/storage-bigtable/src/lib.rs
@@ -3,6 +3,7 @@ use log::*;
 use serde::{Deserialize, Serialize};
 use solana_sdk::{
     clock::{Slot, UnixTimestamp},
+    deserialize_utils::default_on_eof,
     pubkey::Pubkey,
     signature::Signature,
     sysvar::is_sysvar_id,
@@ -81,6 +82,9 @@ fn key_to_slot(key: &str) -> Option<Slot> {
 // StoredConfirmedBlock holds the same contents as ConfirmedBlock, but is slightly compressed and avoids
 // some serde JSON directives that cause issues with bincode
 //
+// Note: in order to continue to support old bincode-serialized bigtable entries, if new fields are
+// added to ConfirmedBlock, they must either be excluded or set to `default_on_eof` here
+//
 #[derive(Serialize, Deserialize)]
 struct StoredConfirmedBlock {
     previous_blockhash: String,
@@ -89,6 +93,7 @@ struct StoredConfirmedBlock {
     transactions: Vec<StoredConfirmedBlockTransaction>,
     rewards: StoredConfirmedBlockRewards,
     block_time: Option<UnixTimestamp>,
+    #[serde(deserialize_with = "default_on_eof")]
     block_height: Option<u64>,
 }