Rental Tenant Space Protocol using ERC4907-based Rentable NFT

Overview

• This is a smart contract protocol that allow tenant owners to rent users who want to use tenant spaces in shopping malls by using ERC4907-based rentable NFT.

• Tenant space NFTs is tokenized-tenant spaces that represent tenant spaces.
  • That makes renting tenant spaces more efficient.

• ERC4907 (Rentable NFT Standard) is used for tenant space NFTs in this protocol.
  • By utilzing ERC4907 in this protocol, owners can rent users tenant spaces by giving "user rights" instead of transferring its tenant space NFTs into users.
  • This workflow makes procesure of renting tenant spaces more transparent who has rights of tenant spaces. (NOTE: In this protocol, owners store their tenant space NFTs into the ShoppingMall contract. Then, the ShoppingMall contract rent users tenant space NFTs on behalf of owners)

Use cases

• This protocol assume use cases such as:
  • The gaming space: Build shopping malls and rent its tenant space. Decentraland like gaming protocol and dApp are potencially able to integrate with this protocol.
  • The real world: Ultimetory, physical shopping malls might be able to be integrated with this protocol for renting its tenant spaces in the future.

Demo Video

• https://youtu.be/S9VmTiBmRb0

Workflow

• This is a diagram that entire workflow is written.
  

Specifications (Integrations)

• ERC4907 (Rentable NFT Standard) is used for a tenant space NFT.
• Chainlink Price Feed is used as the PriceConsumerV3.sol in the ShoppingMall.sol for retrieving ETH/USD price. This price retrieved is used for payment when a tenant space NFT is rent.
  • When a user rent a tenant space NFT

Test (Rinkeby testnet-forking test)

• Unit test of the ShoppingMall.sol (NOTE: This test is the main test that includes entire workflow of this protocol)

yarn test-unit:ShoppingMall

• Unit test of the TenantSpaceNFT.sol

yarn test-unit:TenantSpaceNFT

• Unit test of the TenantSpaceNFTFactory.sol

yarn test-unit:TenantSpaceNFTFactory

• Unit test of the PriceConsumerV3.sol

yarn test-unit:PriceConsumerV3

• Unit test (ERC4907 Demo)

yarn test-unit:ERC4907Demo

Resources

• Chainlink
  • Price Feed on Rinkeby (such as ETH/USD): https://docs.chain.link/docs/ethereum-addresses/#Rinkeby%20Testnet%20(Deprecated)

• ERC-4907：Rentable NFT standard
  • Features：https://twitter.com/zetablockchain/status/1554863652104245253?s=21&t=_sJhuiNQkth5jP4QRu4oTA
  • Workflow：https://ethereum-magicians.org/t/eip4907-erc-721-user-and-expires-extension/8572/2
  • Demo SC & Test：https://eips.ethereum.org/EIPS/eip-4907
  • Code / EIP-4907 Demo：https://github.com/emojidao/EIP4907
  • double-contract： https://github.com/emojidao/double-contract