On-chain IPFS Metadata Registry

Just like it sounds! Use your deployment keys to link metadata stored on IPFS to your contracts. Add categories to allow dapps to publish data about your own address or contracts you've deployed.

v0.0.2 Rinkeby: 0x9E9461B6a1A18df1eCe033d66E615d1eF7222113

v0.0.1 Mainnet: 0xa23E8B119A26D36099ee97F0c7dFb8DB20B50D7D (⚠️ use at your own risk)

Overview

This registry allows deployment keys to submit an IPFS multihash containing metadata (in any format the author wishes) that will be associated with their given contract. After the first successful submission, the msg.sender assumes the delegate role. A delegate can update a multihash for a particular contract, as well as remove any given entry from the registry associated with their particular account.

Delegates can replace themselves with any other ethereum address using the setDelegate method. Once this transaction is mined, they revoke all publishing ability for that given category (including the deployment key) for that particular entry. However, deployers and EOA retain the right to remove entries from the registry regardless of delegate status.

Deployers can add categories, stored as the keccak256 hash of a string representing the categoryID. Once permission is granted other ethereum accounts can submit data on behalf of the deployer. This is useful for dapps that want to have their own hash associated with an address. Next steps for dapp developers would be to create a proxy contract that leverages meta transactions to add a category and submit some initial data in a single transaction using the updateEntry method.

Implementation

IPFS hash is often represented using 46 character long Base58 encoding(e.g. QmahqCsAUAw7zMv6P6Ae8PjCTck7taQA6FgGQLnWdKG7U8). We use the approach layed out here to make storing hashes less expensive. Furthermore, we have two main methods, createEntry which is only used for initialization; requiring the nonce of the deployment key or a user can provide the salt and init_code if the contract uses the create2 opcode. All updates to the registry can rely on the other method signature: updateEntry(address,bytes32,uint8,uint8,bytes32) that does not require the nonce. Once an initial entry is set the msg.sender becomes the delegate. Anyone can commit metadata about their own address making them the default delegate for the deployer category.

Deployers can use addCategory(address,bytes32,address) to permission new entries allowing accounts to publish an entry at a particular categoryID on their behalf and specify an initalDelegate. Also, both deployers and EOA retain the right to revoke publishing priviliges by deleteing a particular category from their approved list by using the deleteCategory(address,bytes32) method which also removes that corresponding entry from the registry.

Usage Notes

• Use null address 0x0000000000000000000000000000000000000000 for the initial delegate when calling addCategory to give msg.sender permissions for a particular categoryID
• The delegate 0xffffffffffffffffffffffffffffffffffffffff allows all ethereum addresses to update the IPFS hash for a given entry
• For createEntry a boolean represents which opcode was used to deploy the contract: create2 === true && create === false

Gas Estimates

Gas price @ 2000000000 gwei

Method	gas (wei)	gas (ether)
createEntry (nonce)	234592000000000	0.000234592
updateEntry	113896000000000	0.000113896
setDelegate	64582000000000	0.000064582
clearEntry	172312000000000	0.000172312
addCategory	96508000000000	0.000096508
deleteCategory	220250000000000	0.00022025

Install

yarn install

Testing

yarn run test