From 9b9a86a506d1522d818e9cf520b2bb49c4347453 Mon Sep 17 00:00:00 2001
From: smypmsa <antonsauchyk@gmail.com>
Date: Fri, 4 Apr 2025 21:31:00 +0000
Subject: [PATCH 1/2] feat: add blockhash caching

---
 src/core/client.py | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/src/core/client.py b/src/core/client.py
index b1b74b4..ac64487 100644
--- a/src/core/client.py
+++ b/src/core/client.py
@@ -34,6 +34,28 @@ class SolanaClient:
         """
         self.rpc_endpoint = rpc_endpoint
         self._client = None
+        self._cached_blockhash: Hash | None = None
+        self._blockhash_lock = asyncio.Lock()
+
+        asyncio.create_task(self.start_blockhash_updater())
+
+    async def start_blockhash_updater(self, interval: float = 5.0):
+        """Start background task to update recent blockhash."""
+        while True:
+            try:
+                blockhash = await self.get_latest_blockhash()
+                async with self._blockhash_lock:
+                    self._cached_blockhash = blockhash
+            except Exception as e:
+                logger.warning(f"Blockhash fetch failed: {e!s}")
+            await asyncio.sleep(interval)
+
+    async def get_cached_blockhash(self) -> Hash:
+        """Return the most recently cached blockhash."""
+        async with self._blockhash_lock:
+            if self._cached_blockhash is None:
+                raise RuntimeError("No cached blockhash available yet")
+            return self._cached_blockhash
 
     async def get_client(self) -> AsyncClient:
         """Get or create the AsyncClient instance.
@@ -128,7 +150,7 @@ class SolanaClient:
             ]
             instructions = fee_instructions + instructions
 
-        recent_blockhash = await self.get_latest_blockhash()
+        recent_blockhash = await self.get_cached_blockhash()
         message = Message(instructions, signer_keypair.pubkey())
         transaction = Transaction([signer_keypair], message, recent_blockhash)
 

From 7cfd89d1ae60371340b31a754b50e4572f852035 Mon Sep 17 00:00:00 2001
From: smypmsa <antonsauchyk@gmail.com>
Date: Fri, 4 Apr 2025 21:38:36 +0000
Subject: [PATCH 2/2] fix: gracefully cancel blockhash updater task

---
 src/core/client.py | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/core/client.py b/src/core/client.py
index ac64487..a39140b 100644
--- a/src/core/client.py
+++ b/src/core/client.py
@@ -36,8 +36,7 @@ class SolanaClient:
         self._client = None
         self._cached_blockhash: Hash | None = None
         self._blockhash_lock = asyncio.Lock()
-
-        asyncio.create_task(self.start_blockhash_updater())
+        self._blockhash_updater_task = asyncio.create_task(self.start_blockhash_updater())
 
     async def start_blockhash_updater(self, interval: float = 5.0):
         """Start background task to update recent blockhash."""
@@ -68,7 +67,14 @@ class SolanaClient:
         return self._client
 
     async def close(self):
-        """Close the client connection if open."""
+        """Close the client connection and stop the blockhash updater."""
+        if self._blockhash_updater_task:
+            self._blockhash_updater_task.cancel()
+            try:
+                await self._blockhash_updater_task
+            except asyncio.CancelledError:
+                pass
+
         if self._client:
             await self._client.close()
             self._client = None