opengsn/workshop2

A sample project to how how to add GSN to a simple Web3 project. See the PRs to see the needed changes.

workshop2's Issues

trustedForwarder init broken in workshop-with-gsn branch

In CaptureTheFlag.sol, the implementation for setting the trustedForwarder on L15 is no longer correct. Suggest using:

_setTrustedForwarder(forwarder);

Originally posted by @Tranquil-Flow in opengsn/workshop#1 (review)

Feedback from presentation

As requested, thought on sharing some feedback on the great presentation! After watching the entire workshop, here are some recommendations:

• 7:12 Ideally it would be great to show early the diff for the changes when implementing GSN. You mention that afterward, but in case someone wanted to skip the manual changes, that would have been great.
• 14:19 There are too many moving parts IMHO to be sharing there, and maybe some visual aid would have been welcomed. Do I require the paymaster in my contract? Update the provider? Redeploy the relayer? Some time ago I put together a diagram for showcasing GSN, happy to chip in here and try to visualize all the moving parts so devs know how to change what where.
• 16:47 Woah, what was that 1 ETH for? Is that needed as a “deposit” for the relayer?

In general, I really enjoyed the walkthrough, but I do see as a challenge how the average developer will go and overhaul their app into implementing the entire stack. From reading this, I see there are 3 challenges needed for OpenGSN adoption:

• Reusing existing forwarder. Requiring only updating msg.sender to _msgSender() is great, but having to redeploy the contract with a forwarder as a constructor is a bit of a turn-off, because a Forwarder needs to be deployed. What would it take for any contract just to take an existing Forwarder? Does it have to be something the contract owner manages?
• Automating boilerplate. My guess is that for 80% of the use cases people will just want a WhitelistPaymaster that they can offline manage via some API they can validate off-chain. How hard would it be to have a script deploy one ready to use?
• Paymaster management. It seems that for the UI to work we need to have a wrapped Paymaster and the RelayProvider, the former having set up the RelayHub and trusted Forwarder address. Is there a roadmap or feature request to allow the creation of tooling to manage these Paymaster contracts? For the average UI guy they just want to update their Metamask modal and go to some dashboard to fund calls for whitelisted addresses. If none exists, are there any existing grants on Gitcoin or similar to be able to contribute to?

Very excited about the project! Take the feedback as a grain of salt and don't hesitate to ping me in Twitter if I can help somehow.

Workshop with paymaster: Error: Rejected relayTransaction call with reason: Cannot read properties of undefined (reading 'contract')

Facing an issue with the whitelist paymaster, the program throws an exception Uncaught (in promise) Error: Rejected relayTransaction call with reason: Cannot read properties of undefined (reading 'contract').

Initially, I was following the youtube tutorial but cloned the paymaster pull request upon encountering this issue. However, the error persists.

For reference, this was the console output prior to the error:

CaptureTheFlag contract 0x0E696947A06550DEf604e82C26fd9E493e576337

identified network: {"chainId":1337,"name":"unknown"}

calling sendAsync{"method":"eth_sendTransaction","params":
[{"gas":"0xb0a4","from":"0xffcf8fdee72ac11b5c542428b35eef5769c409f0","to":"0x0e696947a06550def604e82c26fd9e493e576337","data":"0x239e26f2"}],"id":11,"jsonrpc":"2.0"}

Rejected relayTransaction call with reason: Cannot read properties of undefined (reading 'contract')