ERC721 (non-fungible tokens), ERC165 (introspection) and CryptoKitties

[raulk]

Motivation

EthQL can currently decode ERC20 transactions, and can support any ABI through its decoder service. We now want to extend the breadth the transaction decoding in EthQL by adding support for ERC721 (NFT) and ERC165 (supportsInterface). The latter is a fundamental step towards supporting more contract types in the near-future.

We also want to introduce the notion of application-specific queries with CryptoKitties as an example.

Requirements

• Create erc165 plugin that adds a supportsInterface field in account to query whether that contract supports the interface provided as an argument.

  • Additionally, this plugin should add a service to make it possible for other plugins to query if a contract supports an interface.

• Create erc721 plugin, adding a decoder configuration for the ERC721 log events and transactions.

  • Add a top-level query nftContract(address: "0x...") that exposes the ABI's view operations and public fields, including any relevant field edges (e.g. accounts mainly).
  • ERC721* transaction/log types (in the same spirit as ERC20* transaction/log types) so they can be used from decoded fields.
  • This plugin should use the service exposed by the erc165 plugin to query if a contract is an NFT.

• Create a cryptokitties plugin.

  • Analyse and propose which operations from the CryptoKitties contract should be exposed as EthQL queries.
  • Decide together with the EthQL team the query/field design.
  • Implement all agreed fields according to the definition of done below.

Definition of done

• Test cases with full coverage.
• PR accepted and merged, introducing a new top-level directory for each of the plugins generating an NPM module each (Lerna build #107).
• Code commented, documented and linted.
• README and wiki updated listing and showcasing this functionality.

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

---

This issue now has a funding of 600.0 DAI (600.0 USD @ $1.0/DAI) attached to it.

• If you would like to work on this issue you can 'start work' on the Gitcoin Issue Details page.
• Want to chip in? Add your own contribution here.
• Questions? Checkout Gitcoin Help or the Gitcoin Slack
• $40,714.62 more funded OSS Work available on the Gitcoin Issue Explorer

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

---

Work has been started.

These users each claimed they can complete the work by 3 months, 4 weeks ago.
Please review their action plans below:

1) leonprou has been approved to start work.

Hey,
I'm a Dapp and Fullstack developer, excited to be part of developing the Ethereum ecosystem :)

Plan of work:
First I'd like to implement the ERC165 plugin and present it to the team. Then based on their review I'll make the RC721 plugin and the cryptokitties plugin after it.
Of course I'll make my work with the same structure like the current ERC20 plugin.

Learn more on the Gitcoin Issue Details page.

[gitcoinbot]

💰 A crowdfund contribution worth 55.00000 DAI (55.0 USD @ $1.0/DAI) has been attached to this funded issue from @.💰

Want to chip in also? Add your own contribution here.

[leonprou]

@raulk Hello, any update 👀?

I've got over the codebase and graphql docs, so I think I can handle this.

[spm32]

Hey @leonprou you're good to go! Sorry for the delay on this.

[raulk]

@leonprou 🎉 let me know if you have any questions!

[leonprou]

@ceresstation @raulk thanks guys.

Started working, you can view my progress here. For now I've implemented the ERC165 plugin (though I've done this using a simple resolver).

Also I added a Bytes4 scalar type to the core module, I reckon if it's a part of the Ethereum bytecode it should be there.

Update
Implementing ERC721 I'm noticing strange relationship between it and ERC20. Not sure if one should be depend on the other or some token plugin can be extracted from ERC20.

[elie222]

Erc20 and 721 are very similar. But for example, you don't transfer 100 tokens in Erc721. You transfer kitty with id 123

[elie222]

Erc20 and 721 are very similar. But for example, you don't transfer 100 tokens in Erc721. You transfer kitty with id 123

[gitcoinbot]

@leonprou Hello from Gitcoin Core - are you still working on this issue? Please submit a WIP PR or comment back within the next 3 days or you will be removed from this ticket and it will be returned to an ‘Open’ status. Please let us know if you have questions!

• warning (3 days)
• escalation to mods (6 days)

Funders only: Snooze warnings for 1 day | 3 days | 5 days | 10 days | 100 days

[gitcoinbot]

@leonprou Hello from Gitcoin Core - are you still working on this issue? Please submit a WIP PR or comment back within the next 3 days or you will be removed from this ticket and it will be returned to an ‘Open’ status. Please let us know if you have questions!

• warning (3 days)
• escalation to mods (6 days)

Funders only: Snooze warnings for 1 day | 3 days | 5 days | 10 days | 100 days

[leonprou]

@gitcoinbot sure :)

@elie222 Yes I understand the ERC's. My question was more about code structuring.

[gitcoinbot]

@leonprou Hello from Gitcoin Core - are you still working on this issue? Please submit a WIP PR or comment back within the next 3 days or you will be removed from this ticket and it will be returned to an ‘Open’ status. Please let us know if you have questions!

• warning (3 days)
• escalation to mods (6 days)

Funders only: Snooze warnings for 1 day | 3 days | 5 days | 10 days | 100 days