Merge pull request #213 from nevermined-io/feature/nft_metadata

Adding support to NFTs metadata (ERC-721 & 1155)

contracts/registry/DIDRegistry.sol

@@ -47,7 +47,7 @@ contract DIDRegistry is DIDFactory {
     }
 
     /**
-     * @notice Register a Mintable DID.
+     * @notice Register a Mintable DID using NFTs based in the ERC-1155 standard.
      *
      * @dev The first attribute of a DID registered sets the DID owner.
      *      Subsequent updates record _checksum and update info.
@@ -60,7 +60,7 @@ contract DIDRegistry is DIDFactory {
      * @param _royalties refers to the royalties to reward to the DID creator in the secondary market
      * @param _mint if true it mints the ERC-1155 NFTs attached to the asset
      * @param _activityId refers to activity
-     * @param _attributes refers to the provenance attributes     
+     * @param _nftMetadata refers to the url providing the NFT Metadata     
      * @return size refers to the size of the registry after the register action.
      */
     function registerMintableDID(
@@ -72,22 +72,65 @@ contract DIDRegistry is DIDFactory {
         uint8 _royalties,
         bool _mint,
         bytes32 _activityId,
-        string memory _attributes
+        string memory _nftMetadata
     )
     public
-    onlyValidAttributes(_attributes)
+    onlyValidAttributes(_nftMetadata)
     returns (uint size)
     {
-        uint result = registerDID(_didSeed, _checksum, _providers, _url, _activityId, _attributes);
+        uint result = registerDID(_didSeed, _checksum, _providers, _url, _activityId, '');
         enableAndMintDidNft(
             hashDID(_didSeed, msg.sender),
             _cap,
             _royalties,
-            _mint
+            _mint,
+            _nftMetadata
         );
         return result;
-    }    
-
+    }
+
+    /**
+     * @notice Register a Mintable DID using NFTs based in the ERC-721 standard.
+     *
+     * @dev The first attribute of a DID registered sets the DID owner.
+     *      Subsequent updates record _checksum and update info.
+     *
+     * @param _didSeed refers to decentralized identifier seed (a bytes32 length ID).
+     * @param _checksum includes a one-way HASH calculated using the DDO content.
+     * @param _providers list of addresses that can act as an asset provider     
+     * @param _url refers to the url resolving the DID into a DID Document (DDO), limited to 2048 bytes.
+     * @param _royalties refers to the royalties to reward to the DID creator in the secondary market
+     * @param _mint if true it mints the ERC-1155 NFTs attached to the asset
+     * @param _activityId refers to activity
+     * @param _nftMetadata refers to the url providing the NFT Metadata     
+     * @return size refers to the size of the registry after the register action.
+     */
+    function registerMintableDID721(
+        bytes32 _didSeed,
+        bytes32 _checksum,
+        address[] memory _providers,
+        string memory _url,
+        uint8 _royalties,
+        bool _mint,
+        bytes32 _activityId,
+        string memory _nftMetadata
+    )
+    public
+    onlyValidAttributes(_nftMetadata)
+    returns (uint size)
+    {
+        uint result = registerDID(_didSeed, _checksum, _providers, _url, _activityId, '');
+        enableAndMintDidNft721(
+            hashDID(_didSeed, msg.sender),
+            _royalties,
+            _mint,
+            _nftMetadata
+        );
+        return result;
+    }
+
+
+
     /**
      * @notice Register a Mintable DID.
      *
@@ -101,7 +144,7 @@ contract DIDRegistry is DIDFactory {
      * @param _cap refers to the mint cap
      * @param _royalties refers to the royalties to reward to the DID creator in the secondary market
      * @param _activityId refers to activity
-     * @param _attributes refers to the provenance attributes     
+     * @param _nftMetadata refers to the url providing the NFT Metadata     
      * @return size refers to the size of the registry after the register action.
      */
     function registerMintableDID(
@@ -112,19 +155,19 @@ contract DIDRegistry is DIDFactory {
         uint256 _cap,
         uint8 _royalties,
         bytes32 _activityId,
-        string memory _attributes
+        string memory _nftMetadata
     )
     public
-    onlyValidAttributes(_attributes)
+    onlyValidAttributes(_nftMetadata)
     returns (uint size)
     {
         return registerMintableDID(
-            _didSeed, _checksum, _providers, _url, _cap, _royalties, false, _activityId, _attributes);
+            _didSeed, _checksum, _providers, _url, _cap, _royalties, false, _activityId, _nftMetadata);
     }
 
 
     /**
-     * @notice enableDidNft creates the initial setup of NFTs minting and royalties distribution.
+     * @notice enableDidNft creates the initial setup of NFTs minting and royalties distribution for ERC-1155 NFTs.
      * After this initial setup, this data can't be changed anymore for the DID given, even for the owner of the DID.
      * The reason of this is to avoid minting additional NFTs after the initial agreement, what could affect the 
      * valuation of NFTs of a DID already created.
@@ -134,42 +177,67 @@ contract DIDRegistry is DIDFactory {
      * @param _cap refers to the mint cap
      * @param _royalties refers to the royalties to reward to the DID creator in the secondary market
      * @param _mint if is true mint directly the amount capped tokens and lock in the _lockAddress
+     * @param _nftMetadata refers to the url providing the NFT Metadata          
      */
     function enableAndMintDidNft(
         bytes32 _did,
         uint256 _cap,
         uint8 _royalties,
-        bool _mint
+        bool _mint,
+        string memory _nftMetadata
     )
     public
     onlyDIDOwner(_did)
     returns (bool success)
     {
         didRegisterList.initializeNftConfig(_did, _cap, _royalties);
-
-        if (_mint)    {
+
+        if (bytes(_nftMetadata).length > 0)
+            erc1155.setNFTMetadata(uint256(_did), _nftMetadata);
+
+        if (_royalties > 0)
+            erc1155.setTokenRoyalty(uint256(_did), msg.sender, _royalties);
+
+        if (_mint)
             mint(_did, _cap);
-        }
 
         return super.used(
             keccak256(abi.encode(_did, _cap, _royalties, msg.sender)),
             _did, msg.sender, keccak256('enableNft'), '', 'nft initialization');
     }
-
+
+    /**
+     * @notice enableAndMintDidNft721 creates the initial setup of NFTs minting and royalties distribution for ERC-721 NFTs.
+     * After this initial setup, this data can't be changed anymore for the DID given, even for the owner of the DID.
+     * The reason of this is to avoid minting additional NFTs after the initial agreement, what could affect the 
+     * valuation of NFTs of a DID already created.
+      
+     * @dev update the DID registry providers list by adding the mintCap and royalties configuration
+     * @param _did refers to decentralized identifier (a byte32 length ID)
+     * @param _royalties refers to the royalties to reward to the DID creator in the secondary market
+     * @param _mint if is true mint directly the amount capped tokens and lock in the _lockAddress
+     * @param _nftMetadata refers to the url providing the NFT Metadata          
+     */    
     function enableAndMintDidNft721(
         bytes32 _did,
         uint8 _royalties,
-        bool _mint
+        bool _mint,
+        string memory _nftMetadata
     )
     public
     onlyDIDOwner(_did)
     returns (bool success)
     {
         didRegisterList.initializeNft721Config(_did, _royalties);
 
-        if (_mint)    {
+        if (bytes(_nftMetadata).length > 0)
+            erc721.setNFTMetadata(uint256(_did), _nftMetadata);
+
+        if (_royalties > 0)
+            erc721.setTokenRoyalty(uint256(_did), msg.sender, _royalties);
+
+        if (_mint)
             mint721(_did);
-        }
 
         return super.used(
             keccak256(abi.encode(_did, 1, _royalties, msg.sender)),

contracts/registry/DIDRegistryLibrary.sol

@@ -120,7 +120,7 @@ library DIDRegistryLibrary {
 
         require(!_self.didRegisters[_did].nftInitialized, 'NFT already initialized');
 
-        require(_royalties < 100, 'Invalid royalties number');
+        require(_royalties <= 100, 'Invalid royalties number');
         require(_royalties >= _self.didRegisters[_did].royalties, 'Cannot decrease royalties');
 
         _self.didRegisters[_did].mintCap = _cap;

contracts/token/NFTBase.sol

@@ -0,0 +1,92 @@
+pragma solidity ^0.8.0;
+// Copyright 2020 Keyko GmbH.
+// SPDX-License-Identifier: (Apache-2.0 AND CC-BY-4.0)
+// Code is Apache-2.0 and docs are CC-BY-4.0
+
+import '@openzeppelin/contracts-upgradeable/interfaces/IERC2981Upgradeable.sol';
+import '@openzeppelin/contracts-upgradeable/access/AccessControlUpgradeable.sol';
+import '@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol';
+import '@openzeppelin/contracts-upgradeable/token/ERC1155/ERC1155Upgradeable.sol';
+
+/**
+ *
+ * @dev Implementation of the Royalties EIP-2981 base contract
+ * See https://eips.ethereum.org/EIPS/eip-2981
+ */
+abstract contract NFTBase is IERC2981Upgradeable, OwnableUpgradeable, AccessControlUpgradeable {
+
+    // Mapping from account to proxy approvals
+    mapping (address => bool) internal _proxyApprovals;
+
+    bytes32 public constant MINTER_ROLE = keccak256('MINTER_ROLE');    
+
+    struct RoyaltyInfo {
+        address receiver;
+        uint256 royaltyAmount;
+    }
+
+    struct NFTMetadata {
+        string nftURI;
+    }
+
+    // Mapping of Royalties per tokenId (DID)
+    mapping(uint256 => RoyaltyInfo) internal _royalties;
+
+    mapping(uint256 => NFTMetadata) internal _metadata;
+
+    /** 
+     * Event for recording proxy approvals.
+     */
+    event ProxyApproval(address sender, address operator, bool approved);
+
+
+    function setProxyApproval(
+        address operator, 
+        bool approved
+    ) 
+    public 
+    onlyOwner 
+    virtual 
+    {
+        _proxyApprovals[operator] = approved;
+        emit ProxyApproval(_msgSender(), operator, approved);
+    }
+
+    function _setNFTMetadata(
+        uint256 tokenId,
+        string memory tokenURI
+    )
+    internal
+    {
+        _metadata[tokenId] = NFTMetadata(tokenURI);
+    }
+
+    function _setTokenRoyalty(
+        uint256 tokenId,
+        address receiver,
+        uint256 royaltyAmount
+    )
+    internal
+    {
+        require(royaltyAmount <= 100, 'ERC2981Royalties: Too high');
+        _royalties[tokenId] = RoyaltyInfo(receiver, royaltyAmount);
+    }    
+
+    /**
+     * @inheritdoc	IERC2981Upgradeable
+     */
+    function royaltyInfo(
+        uint256 tokenId,
+        uint256 value
+    )
+    external
+    view
+    override
+    returns (address receiver, uint256 royaltyAmount)
+    {
+        RoyaltyInfo memory royalties = _royalties[tokenId];
+        receiver = royalties.receiver;
+        royaltyAmount = (value * royalties.royaltyAmount) / 100;
+    }
+
+}