feat: add ERC7572 interface for contracts that expose contract level metadata

.changeset/fluffy-bananas-add.md

@@ -0,0 +1,5 @@
+---
+'openzeppelin-solidity': patch
+---
+
+`IERC7572`: Add interface to support contract-level metadata.

contracts/interfaces/draft-IERC6909.sol

@@ -4,6 +4,7 @@
 pragma solidity ^0.8.20;
 
 import {IERC165} from "../utils/introspection/IERC165.sol";
+import {IERC7572} from "./draft-IERC7572.sol";
 
 /**
  * @dev Required interface of an ERC-6909 compliant contract, as defined in the
@@ -102,12 +103,7 @@ interface IERC6909Metadata is IERC6909 {
 /**
  * @dev Optional extension of {IERC6909} that adds content URI functions.
  */
-interface IERC6909ContentURI is IERC6909 {
-    /**
-     * @dev Returns URI for the contract.
-     */
-    function contractURI() external view returns (string memory);
-
+interface IERC6909ContentURI is IERC6909, IERC7572 {
     /**
      * @dev Returns the URI for the token of type `id`.
      */

contracts/interfaces/draft-IERC7572.sol

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: MIT
+// OpenZeppelin Contracts (last updated v5.3.0) (interfaces/draft-IERC7572.sol)
+
+pragma solidity ^0.8.20;
+
+/// @title ERC-7572 Contract Level Metadata
+/// @dev Required interface of an ERC-7572 compliant contract, as defined in the
+/// https://eips.ethereum.org/EIPS/eip-7572[ERC].
+interface IERC7572 {
+    /// @dev This event should be emitted on updates to the contract metadata
+    /// to indicate to offchain indexers that they should query the contract
+    /// for the latest URI.
+    event ContractURIUpdated();
+
+    /// @dev Returns an offchain resource for contract metadata or onchain JSON
+    /// data string (data:application/json;utf8,{}).
+    function contractURI() external view returns (string memory);
+}

contracts/token/ERC6909/extensions/draft-ERC6909ContentURI.sol

@@ -4,6 +4,7 @@
 pragma solidity ^0.8.20;
 
 import {ERC6909} from "../draft-ERC6909.sol";
+import {IERC7572} from "../../../interfaces/draft-IERC7572.sol";
 import {IERC6909ContentURI} from "../../../interfaces/draft-IERC6909.sol";
 
 /**
@@ -13,13 +14,10 @@ contract ERC6909ContentURI is ERC6909, IERC6909ContentURI {
     string private _contractURI;
     mapping(uint256 id => string) private _tokenURIs;
 
-    /// @dev Event emitted when the contract URI is changed. See https://eips.ethereum.org/EIPS/eip-7572[ERC-7572] for details.
-    event ContractURIUpdated();
-
     /// @dev See {IERC1155-URI}
     event URI(string value, uint256 indexed id);
 
-    /// @inheritdoc IERC6909ContentURI
+    /// @inheritdoc IERC7572
     function contractURI() public view virtual override returns (string memory) {
         return _contractURI;
     }