nazt · January 23, 2022 21:43 · Sep 3, 2021 · Sep 1, 2021 · Sep 1, 2021 · Aug 1, 2021
diff --git a/BaseOpenSea.sol b/BaseOpenSea.sol
@@ -3,34 +3,52 @@ pragma solidity ^0.8.0;
 
 /// @title OpenSea contract helper that defines a few things
 /// @author Simon Fremaux (@dievardump)
-/// @dev This is a contract used to add OpenSea's support for gas-less trading
-///      by checking if operator is owner's proxy
+/// @dev This is a contract used to add OpenSea's
+///      gas-less trading and contractURI support
 contract BaseOpenSea {
     string private _contractURI;
-    ProxyRegistry private _proxyRegistry;
+    address private _proxyRegistry;
 
     /// @notice Returns the contract URI function. Used on OpenSea to get details
-    ///         about a contract (owner, royalties etc...)
-    ///         See documentation: https://docs.opensea.io/docs/contract-level-metadata
+    //          about a contract (owner, royalties etc...)
     function contractURI() public view returns (string memory) {
         return _contractURI;
     }
 
-    /// @notice Helper for OpenSea gas-less trading
-    /// @dev Allows to check if `operator` is owner's OpenSea proxy
+    /// @notice Returns the current OS proxyRegistry address registered
+    function proxyRegistry() public view returns (address) {
+        return _proxyRegistry;
+    }
+
+    /// @notice Helper allowing OpenSea gas-less trading by verifying who's operator
+    ///         for owner
+    /// @dev Allows to check if `operator` is owner's OpenSea proxy on eth mainnet / rinkeby
+    ///      or to check if operator is OpenSea's proxy contract on Polygon and Mumbai
     /// @param owner the owner we check for
     /// @param operator the operator (proxy) we check for
     function isOwnersOpenSeaProxy(address owner, address operator)
         public
         view
         returns (bool)
     {
-        ProxyRegistry proxyRegistry = _proxyRegistry;
-        return
-            // we have a proxy registry address
-            address(proxyRegistry) != address(0) &&
-            // current operator is owner's proxy address
-            address(proxyRegistry.proxies(owner)) == operator;
+        address proxyRegistry_ = _proxyRegistry;
+
+        // if we have a proxy registry
+        if (proxyRegistry_ != address(0)) {
+            // on ethereum mainnet or rinkeby use "ProxyRegistry" to
+            // get owner's proxy
+            if (block.chainid == 1 || block.chainid == 4) {
+                return
+                    address(ProxyRegistry(proxyRegistry_).proxies(owner)) ==
+                    operator;
+            } else if (block.chainid == 137 || block.chainid == 80001) {
+                // on Polygon and Mumbai just try with OpenSea's proxy contract
+                // https://docs.opensea.io/docs/polygon-basic-integration
+                return proxyRegistry_ == operator;
+            }
+        }
+
+        return false;
     }
 
     /// @dev Internal function to set the _contractURI
@@ -42,7 +60,7 @@ contract BaseOpenSea {
     /// @dev Internal function to set the _proxyRegistry
     /// @param proxyRegistryAddress the new proxy registry address
     function _setOpenSeaRegistry(address proxyRegistryAddress) internal {
-        _proxyRegistry = ProxyRegistry(proxyRegistryAddress);
+        _proxyRegistry = proxyRegistryAddress;
     }
 }
 

diff --git a/My1155.sol → MyERC1155.sol b/My1155.sol → MyERC1155.sol
@@ -9,7 +9,7 @@ import "./OpenSea/BaseOpenSea.sol";
 /// @title Example of usage of BaseOpenSea
 /// @author Simon Fremaux (@dievardump)
 /// @notice This contract is only an example of how I implement BaseOpenSea
-contract My1155 is
+contract MyERC1155 is
     Ownable,
     ERC1155,
     BaseOpenSea
@@ -18,7 +18,7 @@ contract My1155 is
     /// @param uri_ - the contract base uri
     /// @param openSeaProxyRegistry - the address of OpenSea Proxy Registry
     /// @param contractURI_ - the contract metadata URI (https://docs.opensea.io/docs/contract-level-metadata)
-    constructor(string memory uri_, address openSeaProxyRegistry, string memory contractURI_) ERC155(uri_) {
+    constructor(string memory uri_, address openSeaProxyRegistry, string memory contractURI_) ERC1155(uri_) {
         if (openSeaProxyRegistry != address(0)) {
             _setOpenSeaRegistry(openSeaProxyRegistry);
         }

diff --git a/My1155.sol b/My1155.sol
@@ -0,0 +1,50 @@
+//SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import "@openzeppelin/contracts/access/Ownable.sol";
+import "@openzeppelin/contracts/token/ERC1155/ERC1155.sol";
+
+import "./OpenSea/BaseOpenSea.sol";
+
+/// @title Example of usage of BaseOpenSea
+/// @author Simon Fremaux (@dievardump)
+/// @notice This contract is only an example of how I implement BaseOpenSea
+contract My1155 is
+    Ownable,
+    ERC1155,
+    BaseOpenSea
+{
+    /// @notice constructor
+    /// @param uri_ - the contract base uri
+    /// @param openSeaProxyRegistry - the address of OpenSea Proxy Registry
+    /// @param contractURI_ - the contract metadata URI (https://docs.opensea.io/docs/contract-level-metadata)
+    constructor(string memory uri_, address openSeaProxyRegistry, string memory contractURI_) ERC155(uri_) {
+        if (openSeaProxyRegistry != address(0)) {
+            _setOpenSeaRegistry(openSeaProxyRegistry);
+        }
+
+        if (bytes(contractURI_).length > 0) {
+            _setContractURI(contractURI_);
+        }
+    }
+
+    /// @notice Allows gas-less trading on OpenSea by safelisting the ProxyRegistry of the user
+    /// @dev Override isApprovedForAll to check first if current operator is owner's OpenSea proxy
+    /// @inheritdoc	ERC1155
+    function isApprovedForAll(address owner, address operator)
+        public
+        view
+        override
+        returns (bool)
+    {
+        // allows gas less trading on OpenSea
+        return super.isApprovedForAll(owner, operator) || isOwnersOpenSeaProxy(owner, operator);
+    }
+
+    /// @notice Helper for the owner of the contract to set the new contract URI
+    /// @dev caller needs to be owner
+    /// @param contractURI_ new contract URI
+    function setContractURI(string memory contractURI_) external onlyOwner {
+        _setContractURI(contractURI_);
+    }
+}
diff --git a/MyNFT.sol → MyERC721.sol b/MyNFT.sol → MyERC721.sol
@@ -9,7 +9,7 @@ import "./OpenSea/BaseOpenSea.sol";
 /// @title Example of usage of BaseOpenSea
 /// @author Simon Fremaux (@dievardump)
 /// @notice This contract is only an example of how I implement BaseOpenSea
-contract MyNFT is
+contract MyERC721 is
     Ownable,
     ERC721,
     BaseOpenSea

diff --git a/BaseOpenSea.sol b/BaseOpenSea.sol
@@ -10,7 +10,8 @@ contract BaseOpenSea {
     ProxyRegistry private _proxyRegistry;
 
     /// @notice Returns the contract URI function. Used on OpenSea to get details
-    //          about a contract (owner, royalties etc...)
+    ///         about a contract (owner, royalties etc...)
+    ///         See documentation: https://docs.opensea.io/docs/contract-level-metadata
     function contractURI() public view returns (string memory) {
         return _contractURI;
     }

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -16,7 +16,7 @@ contract MyNFT is
 {
     /// @notice constructor
     /// @param openSeaProxyRegistry - the address of OpenSea Proxy Registry
-    /// @param contractURI_ - the contract metadata URI
+    /// @param contractURI_ - the contract metadata URI (https://docs.opensea.io/docs/contract-level-metadata)
     constructor(address openSeaProxyRegistry, string memory contractURI_) ERC721('MyNFT', 'NFT') {
         if (openSeaProxyRegistry != address(0)) {
             _setOpenSeaRegistry(openSeaProxyRegistry);

diff --git a/README.md b/README.md
@@ -2,11 +2,14 @@
 
 Those two files allow to have easy gas-less trading on OpenSea 
 
-
 # Registries
 
 OpenSea Proxyregistry addresses:
 
 Mainnet: 0xa5409ec958c83c3f309868babaca7c86dcb077c1
 
-Rinkeby: 0xf57b2c51ded3a29e6891aba85459d600256cf317
+Rinkeby: 0xf57b2c51ded3a29e6891aba85459d600256cf317
+
+# Contract level metadata with `contractURI()`
+
+https://docs.opensea.io/docs/contract-level-metadata
diff --git a/README.md b/README.md
@@ -1,7 +1,12 @@
+# Gas-Less trading
+
 Those two files allow to have easy gas-less trading on OpenSea 
 
 
+# Registries
+
 OpenSea Proxyregistry addresses:
 
 Mainnet: 0xa5409ec958c83c3f309868babaca7c86dcb077c1
+
 Rinkeby: 0xf57b2c51ded3a29e6891aba85459d600256cf317
diff --git a/README.md b/README.md
@@ -1,6 +1,7 @@
+Those two files allow to have easy gas-less trading on OpenSea 
+
 
 OpenSea Proxyregistry addresses:
 
 Mainnet: 0xa5409ec958c83c3f309868babaca7c86dcb077c1
-
 Rinkeby: 0xf57b2c51ded3a29e6891aba85459d600256cf317
diff --git a/README.md b/README.md
@@ -0,0 +1,6 @@
+
+OpenSea Proxyregistry addresses:
+
+Mainnet: 0xa5409ec958c83c3f309868babaca7c86dcb077c1
+
+Rinkeby: 0xf57b2c51ded3a29e6891aba85459d600256cf317
diff --git a/BaseOpenSea.sol b/BaseOpenSea.sol
@@ -3,8 +3,8 @@ pragma solidity ^0.8.0;
 
 /// @title OpenSea contract helper that defines a few things
 /// @author Simon Fremaux (@dievardump)
-/// @dev This is a contract used to add OpenSea's gas-less trading support
-///      by verifying if the operator is current owner's Proxy.
+/// @dev This is a contract used to add OpenSea's support for gas-less trading
+///      by checking if operator is owner's proxy
 contract BaseOpenSea {
     string private _contractURI;
     ProxyRegistry private _proxyRegistry;
@@ -26,7 +26,7 @@ contract BaseOpenSea {
     {
         ProxyRegistry proxyRegistry = _proxyRegistry;
         return
-            // we have a proxy address
+            // we have a proxy registry address
             address(proxyRegistry) != address(0) &&
             // current operator is owner's proxy address
             address(proxyRegistry.proxies(owner)) == operator;

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -29,7 +29,7 @@ contract MyNFT is
 
     /// @notice Allows gas-less trading on OpenSea by safelisting the ProxyRegistry of the user
     /// @dev Override isApprovedForAll to check first if current operator is owner's OpenSea proxy
-    /// @inheritdoc	ERC721Upgradeable
+    /// @inheritdoc	ERC721
     function isApprovedForAll(address owner, address operator)
         public
         view

diff --git a/BaseOpenSea.sol b/BaseOpenSea.sol
@@ -3,19 +3,12 @@ pragma solidity ^0.8.0;
 
 /// @title OpenSea contract helper that defines a few things
 /// @author Simon Fremaux (@dievardump)
-/// @dev This is a contract used to add OpenSea's support
-///      This is a contract made to work with upgradeable contract,
-///      if you ever add state variables, you must update __gap accordingly.
-///      -> https://forum.openzeppelin.com/t/what-exactly-is-the-reason-for-uint256-50-private-gap/798
-///      if you do not use Upgradeable contracts, you should comment the line that defines __gap
+/// @dev This is a contract used to add OpenSea's gas-less trading support
+///      by verifying if the operator is current owner's Proxy.
 contract BaseOpenSea {
     string private _contractURI;
     ProxyRegistry private _proxyRegistry;
 
-    /// @dev If you ever add new state variable please add BEFORE this comment, and update __gap accordingly
-    /// @dev https://forum.openzeppelin.com/t/what-exactly-is-the-reason-for-uint256-50-private-gap/798
-    uint256[10] private __gap;
-
     /// @notice Returns the contract URI function. Used on OpenSea to get details
     //          about a contract (owner, royalties etc...)
     function contractURI() public view returns (string memory) {

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -37,11 +37,7 @@ contract MyNFT is
         returns (bool)
     {
         // allows gas less trading on OpenSea
-        if (isOwnersOpenSeaProxy(owner, operator)) {
-            return true;
-        }
-
-        return super.isApprovedForAll(owner, operator);
+        return super.isApprovedForAll(owner, operator) || isOwnersOpenSeaProxy(owner, operator);
     }
 
     /// @notice Helper for the owner of the contract to set the new contract URI

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -17,7 +17,7 @@ contract MyNFT is
     /// @notice constructor
     /// @param openSeaProxyRegistry - the address of OpenSea Proxy Registry
     /// @param contractURI_ - the contract metadata URI
-    function constructor(address openSeaProxyRegistry, string memory contractURI_) ERC721('MyNFT', 'NFT') {
+    constructor(address openSeaProxyRegistry, string memory contractURI_) ERC721('MyNFT', 'NFT') {
         if (openSeaProxyRegistry != address(0)) {
             _setOpenSeaRegistry(openSeaProxyRegistry);
         }

diff --git a/BaseOpenSea.sol b/BaseOpenSea.sol
@@ -2,7 +2,7 @@
 pragma solidity ^0.8.0;
 
 /// @title OpenSea contract helper that defines a few things
-/// @author Simon Fremaux (@dievrarump)
+/// @author Simon Fremaux (@dievardump)
 /// @dev This is a contract used to add OpenSea's support
 ///      This is a contract made to work with upgradeable contract,
 ///      if you ever add state variables, you must update __gap accordingly.

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -10,7 +10,8 @@ import "./OpenSea/BaseOpenSea.sol";
 /// @author Simon Fremaux (@dievardump)
 /// @notice This contract is only an example of how I implement BaseOpenSea
 contract MyNFT is
-    Ownable
+    Ownable,
+    ERC721,
     BaseOpenSea
 {
     /// @notice constructor

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -15,10 +15,15 @@ contract MyNFT is
 {
     /// @notice constructor
     /// @param openSeaProxyRegistry - the address of OpenSea Proxy Registry
-    function constructor(address openSeaProxyRegistry) ERC721('MyNFT', 'NFT') {
+    /// @param contractURI_ - the contract metadata URI
+    function constructor(address openSeaProxyRegistry, string memory contractURI_) ERC721('MyNFT', 'NFT') {
         if (openSeaProxyRegistry != address(0)) {
             _setOpenSeaRegistry(openSeaProxyRegistry);
         }
+
+        if (bytes(contractURI_).length > 0) {
+            _setContractURI(contractURI_);
+        }
     }
 
     /// @notice Allows gas-less trading on OpenSea by safelisting the ProxyRegistry of the user

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -22,7 +22,7 @@ contract MyNFT is
     }
 
     /// @notice Allows gas-less trading on OpenSea by safelisting the ProxyRegistry of the user
-    /// @dev Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-less listings.
+    /// @dev Override isApprovedForAll to check first if current operator is owner's OpenSea proxy
     /// @inheritdoc	ERC721Upgradeable
     function isApprovedForAll(address owner, address operator)
         public

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -21,7 +21,7 @@ contract MyNFT is
         }
     }
 
-    /// @notice Allows gas-less trading on OpenSea by whitelisting the ProxyRegistry of the user
+    /// @notice Allows gas-less trading on OpenSea by safelisting the ProxyRegistry of the user
     /// @dev Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-less listings.
     /// @inheritdoc	ERC721Upgradeable
     function isApprovedForAll(address owner, address operator)

diff --git a/MyNFT.sol b/MyNFT.sol
@@ -14,7 +14,12 @@ contract MyNFT is
     BaseOpenSea
 {
     /// @notice constructor
-    function constructor() ERC721('MyNFT', 'NFT') {}
+    /// @param openSeaProxyRegistry - the address of OpenSea Proxy Registry
+    function constructor(address openSeaProxyRegistry) ERC721('MyNFT', 'NFT') {
+        if (openSeaProxyRegistry != address(0)) {
+            _setOpenSeaRegistry(openSeaProxyRegistry);
+        }
+    }
 
     /// @notice Allows gas-less trading on OpenSea by whitelisting the ProxyRegistry of the user
     /// @dev Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-less listings.

diff --git a/BaseOpenSea.sol b/BaseOpenSea.sol
@@ -0,0 +1,59 @@
+//SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+/// @title OpenSea contract helper that defines a few things
+/// @author Simon Fremaux (@dievrarump)
+/// @dev This is a contract used to add OpenSea's support
+///      This is a contract made to work with upgradeable contract,
+///      if you ever add state variables, you must update __gap accordingly.
+///      -> https://forum.openzeppelin.com/t/what-exactly-is-the-reason-for-uint256-50-private-gap/798
+///      if you do not use Upgradeable contracts, you should comment the line that defines __gap
+contract BaseOpenSea {
+    string private _contractURI;
+    ProxyRegistry private _proxyRegistry;
+
+    /// @dev If you ever add new state variable please add BEFORE this comment, and update __gap accordingly
+    /// @dev https://forum.openzeppelin.com/t/what-exactly-is-the-reason-for-uint256-50-private-gap/798
+    uint256[10] private __gap;
+
+    /// @notice Returns the contract URI function. Used on OpenSea to get details
+    //          about a contract (owner, royalties etc...)
+    function contractURI() public view returns (string memory) {
+        return _contractURI;
+    }
+
+    /// @notice Helper for OpenSea gas-less trading
+    /// @dev Allows to check if `operator` is owner's OpenSea proxy
+    /// @param owner the owner we check for
+    /// @param operator the operator (proxy) we check for
+    function isOwnersOpenSeaProxy(address owner, address operator)
+        public
+        view
+        returns (bool)
+    {
+        ProxyRegistry proxyRegistry = _proxyRegistry;
+        return
+            // we have a proxy address
+            address(proxyRegistry) != address(0) &&
+            // current operator is owner's proxy address
+            address(proxyRegistry.proxies(owner)) == operator;
+    }
+
+    /// @dev Internal function to set the _contractURI
+    /// @param contractURI_ the new contract uri
+    function _setContractURI(string memory contractURI_) internal {
+        _contractURI = contractURI_;
+    }
+
+    /// @dev Internal function to set the _proxyRegistry
+    /// @param proxyRegistryAddress the new proxy registry address
+    function _setOpenSeaRegistry(address proxyRegistryAddress) internal {
+        _proxyRegistry = ProxyRegistry(proxyRegistryAddress);
+    }
+}
+
+contract OwnableDelegateProxy {}
+
+contract ProxyRegistry {
+    mapping(address => OwnableDelegateProxy) public proxies;
+}
diff --git a/MyNFT.sol b/MyNFT.sol
@@ -0,0 +1,42 @@
+//SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import "@openzeppelin/contracts/access/Ownable.sol";
+import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
+
+import "./OpenSea/BaseOpenSea.sol";
+
+/// @title Example of usage of BaseOpenSea
+/// @author Simon Fremaux (@dievardump)
+/// @notice This contract is only an example of how I implement BaseOpenSea
+contract MyNFT is
+    Ownable
+    BaseOpenSea
+{
+    /// @notice constructor
+    function constructor() ERC721('MyNFT', 'NFT') {}
+
+    /// @notice Allows gas-less trading on OpenSea by whitelisting the ProxyRegistry of the user
+    /// @dev Override isApprovedForAll to whitelist user's OpenSea proxy accounts to enable gas-less listings.
+    /// @inheritdoc	ERC721Upgradeable
+    function isApprovedForAll(address owner, address operator)
+        public
+        view
+        override
+        returns (bool)
+    {
+        // allows gas less trading on OpenSea
+        if (isOwnersOpenSeaProxy(owner, operator)) {
+            return true;
+        }
+
+        return super.isApprovedForAll(owner, operator);
+    }
+
+    /// @notice Helper for the owner of the contract to set the new contract URI
+    /// @dev caller needs to be owner
+    /// @param contractURI_ new contract URI
+    function setContractURI(string memory contractURI_) external onlyOwner {
+        _setContractURI(contractURI_);
+    }
+}