Fix non-0x-prefixed raw tx for signing middleware due to hexbytes cha…

…nge.

newsfragments/3471.bugfix.rst

@@ -0,0 +1 @@
+Fix a bug with newer ``hexbytes`` versions that yield non-0x-prefixed hex for ``HexBytes``: ``raw_transaction.hex()`` -> ``raw_transaction.to_0x_hex()``.

web3/_utils/module_testing/eth_module.py

@@ -88,6 +88,7 @@
 )
 from web3.middleware import (
     ExtraDataToPOAMiddleware,
+    SignAndSendRawMiddlewareBuilder,
 )
 from web3.types import (
     ENS,
@@ -725,6 +726,26 @@ async def test_async_eth_send_raw_transaction(
         txn_hash = await async_w3.eth.send_raw_transaction(signed.raw_transaction)
         assert txn_hash == HexBytes(signed.hash)
 
+    @pytest.mark.asyncio
+    async def test_async_sign_and_send_raw_middleware(
+        self, async_w3: "AsyncWeb3", keyfile_account_pkey: HexStr
+    ) -> None:
+        keyfile_account = async_w3.eth.account.from_key(keyfile_account_pkey)
+        txn: TxParams = {
+            "from": keyfile_account.address,
+            "to": keyfile_account.address,
+            "value": Wei(0),
+            "gas": 21000,
+        }
+        async_w3.middleware_onion.add(
+            SignAndSendRawMiddlewareBuilder.build(keyfile_account), "signing"
+        )
+        txn_hash = await async_w3.eth.send_transaction(txn)
+        assert isinstance(txn_hash, HexBytes)
+
+        # clean up
+        async_w3.middleware_onion.remove("signing")
+
     @pytest.mark.asyncio
     async def test_GasPriceStrategyMiddleware(
         self,
@@ -3716,6 +3737,25 @@ def test_eth_send_raw_transaction(
         txn_hash = w3.eth.send_raw_transaction(signed.raw_transaction)
         assert txn_hash == HexBytes(signed.hash)
 
+    def test_sign_and_send_raw_middleware(
+        self, w3: "Web3", keyfile_account_pkey: HexStr
+    ) -> None:
+        keyfile_account = w3.eth.account.from_key(keyfile_account_pkey)
+        txn: TxParams = {
+            "from": keyfile_account.address,
+            "to": keyfile_account.address,
+            "value": Wei(0),
+            "gas": 21000,
+        }
+        w3.middleware_onion.add(
+            SignAndSendRawMiddlewareBuilder.build(keyfile_account), "signing"
+        )
+        txn_hash = w3.eth.send_transaction(txn)
+        assert isinstance(txn_hash, HexBytes)
+
+        # cleanup
+        w3.middleware_onion.remove("signing")
+
     def test_eth_call(self, w3: "Web3", math_contract: "Contract") -> None:
         txn_params = math_contract._prepare_transaction(
             abi_element_identifier="add",

web3/middleware/signing.py

@@ -189,7 +189,7 @@ def request_processor(self, method: "RPCEndpoint", params: Any) -> Any:
 
                 return (
                     RPCEndpoint("eth_sendRawTransaction"),
-                    [raw_tx.hex()],
+                    [raw_tx.to_0x_hex()],
                 )
 
     # -- async -- #
@@ -220,5 +220,5 @@ async def async_request_processor(self, method: "RPCEndpoint", params: Any) -> A
 
                 return (
                     RPCEndpoint("eth_sendRawTransaction"),
-                    [raw_tx.hex()],
+                    [raw_tx.to_0x_hex()],
                 )