Web3.py: Add support for Goerli

[fubuloubu]

https://github.com/goerli/testnet

Motivation

Goerli is the dapp testnet of the future. All PoA testnet chains will bow before it's power (and eventually move their ETH?) Support should be added for the modifications to the consensus data required to support it so that I can interact with the new chain!

[veox]

AFAIK it uses Rinkeby's Clique consensus engine; have you tried using a Goerli node with Rinkeby instructions (the one-line middleware addition)?

[fubuloubu]

I've had problems getting Rinkeby to work before as well. I can try that though. What's the name of the middleware for that?

[veox]

geth_poa_middleware, detailed in this Middleware sub-section.

---

To think of it, might need a rename; with Goerli, it's no longer just geth. Provided it works, that is.

[fubuloubu]

Yeah, I'm not sure what the difference is but I'm pretty sure there is a difference

[pipermerriam]

cc @carver who may know. I think geth_poa_middleware just needs to be renamed to clique_poa_middleware

[fubuloubu]

p.s. Added #1234 after realizing I forgot the middleware for Infura when I did that change.

[veox]

have you tried using a Goerli node

Tried it locally myself, with git master version of go-ethereum, which added support for geth --goerli a day ago.

I've ran a simple block filter script with that as the back-end, and it worked just fine. Simply symlinked the Goerli socket location to ~/.ethereum/geth.ipc.

I think the changes that'll be required in web3.py are:

• look for the IPC socket in ~/.ethereum/goerli/geth.ipc, too, when using web3.auto; similar for parity-ethereum and any other supported node impln-s;
• add the middleware when using Goerli, just as PR #1234 does for Rinkeby;
• aforementioned rename to clique_poa_middleware would be nice ^_^ - don't forget the docs if so.

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For those curious, a topic @fubuloubu started on Infura's forum for when they add support.

[carver]

• look for the IPC socket in ~/.ethereum/goerli/geth.ipc, too, when using web3.auto; similar for parity-ethereum and any other supported node impln-s;

Yup! Although if I remember correctly we are moving away from dynamically/automatically switching between testnet and mainnet depending on which is available. (Seems like a bad idea to implicitly switch between testnet and mainnet) So maybe it's time for something like:

from web3.auto.geth.goerli import w3
# plus an alias, since I think we should encourage goerli as the "default" testnet:
from web3.auto.geth.testnet import w3

... and maybe we could make one that looks for the goerli endpoint for any known node software, with something like:

from web3.auto.goerli import w3
# plus an alias, since I think we should encourage goerli as the "default" testnet:
from web3.auto.testnet import w3

So that would look for: geth, parity, trinity, etc

• add the middleware when using Goerli, just as PR #1234 does for Rinkeby;

:+1:

• aforementioned rename to clique_poa_middleware would be nice ^_^ - don't forget the docs if so.

:+1: