I wanted to store the metadata of my ERC721 tokens on IPFS. Currently, I am inheriting from OpenZeppelin ERC721.sol contract, and I saw there is a tokenURI function which returns the URI of the metadata. This token URI function build its URI based on the baseURI concatenated with the tokenID. The thing is if I would like to store on IPFS, the URI will be the hash of the content stored, and it will be nowhere close to the URI built by the tokenURI function. Thus I am unsure of how to build the tokenURI in my case? (of course I could build it manually, but is there a way to write a function to automate this?)
1 Answer
Set your _baseURI
as "ipfs://" and put the content hash into _tokenURI
.
The relevant code is at https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC721/ERC721.sol#L141-L144
The result is your tokenURI(tokenID)
will be the full IPFS URI.