Extrinsic hash is None for unsigned extrinsic

[hemz10]

I am trying to decode extrinsic for a block using get_block method from py-substrate interface. For an extrinsic with no signer, extrinsic hash is none. How do we get extrinsic hash when there is no signer.

Extrinsic hash is assigned to None here when there is no signer

Here is my code example:

from substrateinterface import SubstrateInterface
def polkadot_decodeExtrinsic(self):
    substrate = SubstrateInterface(url="https://rpc.polkadot.io")
    block = substrate.get_block(
        block_hash='0xa25f3b3840989455423acd6626ceb9dc91b9d2044ee8430f234f8c0c46ed728c')
        for i, extrinsic in enumerate(block['extrinsics']):
                assert (extrinsic.value["extrinsic_hash"]) is None
               # This should not be none

Expected Behaviour:
The Hash should not be None and there should be some value as seen in polkascan explorer for the first and as well as second extrinsic.

Reference:
The same issue was reported. Issue link fyr here

[arjanz]

Thanks for pointing this out, the previous fix dud generate but still didn't include the extrinsic hash when decoding unsigned extrinsics.

Original rationale was that uniqueness cannot be guaranteed for unsigned extrinsics, but in practice collisions don't happen that often.

[arjanz]

Included in release: https://github.com/polkascan/py-scale-codec/releases/tag/v1.2.7

[hemz10]

Thank you, It's working now !!