JSON value of type string is not of expected type array on `testmempoolaccept'

[MPins]

---

JSONRPCException Traceback (most recent call last)
Cell In[15], line 3
1 # Do not brodcast, try changing it first
2 node.sendrawtransaction(signed_tx.hex())
----> 3 node.testmempoolaccept(signed_tx.hex())

File ~/bitcoin/test/functional/test_framework/coverage.py:49, in AuthServiceProxyWrapper.call(self, *args, **kwargs)
43 def call(self, *args, **kwargs):
44 """
45 Delegates to AuthServiceProxy, then writes the particular RPC method
46 called to a file.
47
48 """
---> 49 return_val = self.auth_service_proxy_instance.call(*args, **kwargs)
50 self._log_call()
51 return return_val

File ~/bitcoin/test/functional/test_framework/authproxy.py:144, in AuthServiceProxy.call(self, *args, **argsn)
142 response, status = self._request('POST', self.__url.path, postdata.encode('utf-8'))
143 if response['error'] is not None:
--> 144 raise JSONRPCException(response['error'], status)
145 elif 'result' not in response:
146 raise JSONRPCException({
147 'code': -343, 'message': 'missing JSON-RPC result'}, status)

JSONRPCException: Wrong type passed:
{
"Position 1 (rawtxs)": "JSON value of type string is not of expected type array"
} (-3)

[MPins]

I can investigate further if you think it is worth it.

[DariusParvin]

hey @MPins thanks for posting this. Could you provide some more context around how to reproduce this issue? I think you're the first so it's unclear if it's something to do with your setup or a bug in the code. This kind of bug seems unexpected. Could you also include what version of bitcoin core you're running in case that's the issue too.

[MPins]

I 'm just following the Chapter1-legacy -> Maleability of ECDSA and before broadcast the transaction (on regtest mode) I tried the testmempoolaccept where I got the error.

I'm running Bitcoin Core Version: 240001 (/Satoshi:24.0.1(testnode0)/).

[DariusParvin]

thanks a lot @MPins , that context helps. And yes i see the issue now. That command is using testmempoolaccept incorrectly:

node.testmempoolaccept(signed_tx.hex()) , passing in the tx hex as just a raw string, when it should be in an array e.g.:

node.testmempoolaccept(rawtxs=[signed_tx.hex()]).

If you have the chance can you try that command instead and confirm it works? If so, feel free to open a PR to fix it, or otherwise i can get round to testing it this weekend

[MPins]

It works perfectly!