ERC-1155 Metadata URI

The OpenZeppelin ERC-1155 Metadata URI extension is needed to manage and store URIs for individual tokens. This extension allows each token to have its own unique URI, which points to a JSON file that conforms to the ERC-1155 Metadata URI JSON Schema. This is particularly useful for non-fungible tokens (NFTs) where each token is unique and may have different metadata.

Usage

In order to make an ERC-1155 token with Metadata URI flavour, you need to add the following code to your contract:

use openzeppelin_stylus::{
    token::{
        erc1155,
        erc1155::{
            extensions::{Erc1155MetadataUri, IErc1155MetadataUri},
            Erc1155, IErc1155,
        },
    },
    utils::introspection::erc165::IErc165,
};

#[entrypoint]
#[storage]
struct Erc1155MetadataUriExample {
    erc1155: Erc1155,
    metadata_uri: Erc1155MetadataUri,
}

#[public]
#[implements(IErc1155<Error = erc1155::Error>, IErc1155MetadataUri, IErc165)]
impl Erc1155MetadataUriExample {
    #[constructor]
    fn constructor(&mut self, uri: String) {
        self.metadata_uri.constructor(uri);
    }
}

#[public]
impl IErc1155 for Erc1155MetadataUriExample {
    type Error = erc1155::Error;

    fn balance_of(&self, account: Address, id: U256) -> U256 {
        self.erc1155.balance_of(account, id)
    }

    fn balance_of_batch(
        &self,
        accounts: Vec<Address>,
        ids: Vec<U256>,
    ) -> Result<Vec<U256>, Self::Error> {
        self.erc1155.balance_of_batch(accounts, ids)
    }

    fn set_approval_for_all(
        &mut self,
        operator: Address,
        approved: bool,
    ) -> Result<(), Self::Error> {
        self.erc1155.set_approval_for_all(operator, approved)
    }

    fn is_approved_for_all(&self, account: Address, operator: Address) -> bool {
        self.erc1155.is_approved_for_all(account, operator)
    }

    fn safe_transfer_from(
        &mut self,
        from: Address,
        to: Address,
        id: U256,
        value: U256,
        data: Bytes,
    ) -> Result<(), Self::Error> {
        self.erc1155.safe_transfer_from(from, to, id, value, data)
    }

    fn safe_batch_transfer_from(
        &mut self,
        from: Address,
        to: Address,
        ids: Vec<U256>,
        values: Vec<U256>,
        data: Bytes,
    ) -> Result<(), Self::Error> {
        self.erc1155.safe_batch_transfer_from(from, to, ids, values, data)
    }
}

#[public]
impl IErc1155MetadataUri for Erc1155MetadataUriExample {
    fn uri(&self, token_id: U256) -> String {
        self.metadata_uri.uri(token_id)
    }
}

#[public]
impl IErc165 for Erc1155MetadataUriExample {
    fn supports_interface(&self, interface_id: FixedBytes<4>) -> bool {
        self.erc1155.supports_interface(interface_id)
            || self.metadata_uri.supports_interface(interface_id)
    }
}