Fix reference scripts fetched from ogmios (#254)

* Test transaction chaining

* Fix reference scripts fetched from ogmios

* Add tests

* Remove unused import

---------

Co-authored-by: Jerry <jerrycgh@gmail.com>

Author: nielstron

integration-test/test/test_plutus.py

@@ -311,3 +311,63 @@ def test_plutus_v2_ref_script(self):
         self.chain_context.submit_tx(signed_tx)
 
         self.assert_output(taker_address, take_output)
+
+    @retry(tries=TEST_RETRIES, backoff=1.5, delay=6, jitter=(0, 4))
+    @pytest.mark.post_alonzo
+    def test_transaction_chaining(self):
+        giver_address = Address(self.payment_vkey.hash(), network=self.NETWORK)
+        builder = TransactionBuilder(self.chain_context)
+        builder.add_input_address(giver_address)
+        builder.add_output(TransactionOutput(giver_address, 50000000))
+        tx1 = builder.build_and_sign([self.payment_skey], giver_address)
+
+        utxo_to_spend = UTxO(
+            TransactionInput(tx1.id, 0), tx1.transaction_body.outputs[0]
+        )
+
+        builder = TransactionBuilder(self.chain_context)
+        builder.add_input(utxo_to_spend)
+        builder.add_output(TransactionOutput(giver_address, 25000000))
+        tx2 = builder.build_and_sign([self.payment_skey], giver_address)
+
+        self.chain_context.submit_tx(tx1)
+        self.chain_context.submit_tx(tx2)
+
+    @retry(tries=TEST_RETRIES, backoff=1.5, delay=6, jitter=(0, 4))
+    @pytest.mark.post_alonzo
+    def test_get_plutus_script(self):
+        # ----------- Giver give ---------------
+        with open("./plutus_scripts/fortytwoV2.plutus", "r") as f:
+            script_hex = f.read()
+            forty_two_script = PlutusV2Script(cbor2.loads(bytes.fromhex(script_hex)))
+
+        script_hash = plutus_script_hash(forty_two_script)
+
+        script_address = Address(script_hash, network=self.NETWORK)
+
+        giver_address = Address(self.payment_vkey.hash(), network=self.NETWORK)
+
+        builder = TransactionBuilder(self.chain_context)
+        builder.add_input_address(giver_address)
+        builder.add_output(
+            TransactionOutput(script_address, 50000000, script=forty_two_script)
+        )
+
+        signed_tx = builder.build_and_sign([self.payment_skey], giver_address)
+
+        print("############### Transaction created ###############")
+        print(signed_tx)
+        print(signed_tx.to_cbor_hex())
+        print("############### Submitting transaction ###############")
+        self.chain_context.submit_tx(signed_tx)
+        time.sleep(3)
+
+        utxos = self.chain_context.utxos(script_address)
+
+        assert utxos[0].output.script == forty_two_script
+
+
+class TestPlutusOgmiosOnly(TestPlutus):
+    @classmethod
+    def setup_class(cls):
+        cls.chain_context._kupo_url = None

pycardano/backend/ogmios.py

@@ -4,7 +4,6 @@
 from enum import Enum
 from typing import Any, Dict, List, Optional, Tuple, Union
 
-import cbor2
 import requests
 import websocket
 from cachetools import Cache, LRUCache, TTLCache, func
@@ -466,9 +465,9 @@ def _utxo_from_ogmios_result(self, result) -> UTxO:
         script = output.get("script", None)
         if script:
             if "plutus:v2" in script:
-                script = PlutusV2Script(cbor2.loads(bytes.fromhex(script["plutus:v2"])))
+                script = PlutusV2Script(bytes.fromhex(script["plutus:v2"]))
             elif "plutus:v1" in script:
-                script = PlutusV1Script(cbor2.loads(bytes.fromhex(script["plutus:v1"])))
+                script = PlutusV1Script(bytes.fromhex(script["plutus:v1"]))
             else:
                 raise ValueError("Unknown plutus script type")
         datum_hash = (