How to use filters with web3py to get event logs for a smart contract?

Question

I'm looking to get event logs for a smart contract and I'm using Infura nodes for this. According to the documentation provided here , I tried running

new_block_filter = web3.eth.filter('latest')

I think this should have been

new_block_filter = w3.eth.filter('latest')

where w3 should be something like

w3 = Web3(HTTPProvider("https://mainnet.infura.io/v3/infura-project-id"))

but there's an error in the documentation. Anyways I tried this which I believe is the simplest way to create a filter as well the methods mentioned here .

Both of these result in an error that looks like

Traceback (most recent call last): File "", line 1, in File "/home/username/.local/lib/python3.6/site-packages/web3/eth.py", line 333, in filter [filter_params], File "/home/username/.local/lib/python3.6/site-packages/web3/manager.py", line 112, in request_blocking raise ValueError(response["error"])

ValueError: {'code': -32601, 'message': 'The method eth_newFilter does not exist/is not available'}

Any ideas on how to create and use these filters and further how to get event logs for a smart contract when the topic parameter is known.

Answer 1

The error message means what it says. Infura doesn't support the RPC method eth_newFilter over HTTPS, which is what your code ends up calling.

I believe the same code should work if you connect via WebSocket instead.