Migrate metadata to new ERC721 contract

[abcoathup]

Hi Rogers (@allurco),

Welcome to the community

If you have a predetermined number of tokens, then you could use a scheme where you store all the metadata in a directory in IPFS in advance.
For example:
baseURI: https://ipfs.io/ipfs/QmUm25XMSnUvxvi7XE9Xr8XwRdkNosmTDyKDDyxMajjytv/

Making the tokenURI be the baseURI concatenated with the tokenID as a string.
For example:
https://ipfs.io/ipfs/QmUm25XMSnUvxvi7XE9Xr8XwRdkNosmTDyKDDyxMajjytv/0
https://ipfs.io/ipfs/QmUm25XMSnUvxvi7XE9Xr8XwRdkNosmTDyKDDyxMajjytv/1

This would reduce the cost of minting as you aren't having to store a tokenURI per tokenID.

Alternatively, you could use the extension ERC721URIStorage to store an IPFS hash per tokenID. Though this would have higher minting costs.

There is also a third option, of using centralized metadata. Your metadata could even use an image in IPFS.
For example:
baseURI: https://example.com/token/

@allurco

If we create a new contract, would it be possible to update the storage of the original contract?

Unless you setup your original token (preERC721) contract to do that, then I assume not.

@allurco

If we submit to opensea or other platform should we submit the new contract with the metadata or all the contracts?

You would just submit your ERC721 contract to OpenSea and other marketplaces.

Are you allowing existing token holders to convert to an ERC721? Either by wrapping their existing token as an ERC721 or swapping it.

@allurco

Can we use your ERC721URIStorage contract and probably IERC721Metadata.sol?

Yes! Please see the Contracts 4.0 Timeline.