feat: add WhitelistAccessModule, along with its interface

solidity/contracts/examples/modules/access/WhitelistAccessModule.sol

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+import {IModule, Module} from '@defi-wonderland/prophet-core/solidity/contracts/Module.sol';
+import {IOracle} from '@defi-wonderland/prophet-core/solidity/interfaces/IOracle.sol';
+
+import {
+  IAccessModule,
+  IWhitelistAccessModule
+} from '../../../../interfaces/examples/modules/access/IWhitelistAccessModule.sol';
+
+contract WhitelistAccessModule is Module, IWhitelistAccessModule {
+  /// @inheritdoc IWhitelistAccessModule
+  mapping(address _user => mapping(address _allowedSender => bool _status)) public whitelist;
+
+  constructor(IOracle _oracle) Module(_oracle) {}
+
+  /// @inheritdoc IModule
+  function moduleName() external pure returns (string memory _moduleName) {
+    return 'WhitelistAccessModule';
+  }
+
+  /// @inheritdoc IAccessModule
+  function decodeAccessControlParameters(bytes calldata _data)
+    public
+    pure
+    returns (IAccessModule.AccessControlParameters memory _params)
+  {
+    _params = abi.decode(_data, (IAccessModule.AccessControlParameters));
+  }
+
+  /// @inheritdoc IAccessModule
+  function hasAccess(bytes calldata _data) external view returns (bool _hasAccess) {
+    IAccessModule.AccessControlParameters memory _params = decodeAccessControlParameters(_data);
+
+    _hasAccess = whitelist[_params.accessControl.user][_params.sender];
+  }
+
+  /// @inheritdoc IWhitelistAccessModule
+  function setSenderApproval(address _allowedSender, bool _status) external {
+    whitelist[msg.sender][_allowedSender] = _status;
+    emit SetApproval(msg.sender, _allowedSender, _status);
+  }
+}

solidity/interfaces/examples/modules/access/IWhitelistAccessModule.sol

@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+import {IAccessModule} from '@defi-wonderland/prophet-core/solidity/interfaces/modules/access/IAccessModule.sol';
+
+/*
+  * @title IWhitelistAccessModule
+  */
+interface IWhitelistAccessModule is IAccessModule {
+  /*///////////////////////////////////////////////////////////////
+                              STRUCTS
+  //////////////////////////////////////////////////////////////*/
+
+  /*///////////////////////////////////////////////////////////////
+                              EVENTS
+  //////////////////////////////////////////////////////////////*/
+
+  /**
+   * @dev Emitted when the approval status of a user is updated.
+   * @param _user The address of the user authorizing a sender.
+   * @param _sender The address of the sender whose status is being updated
+   * @param _status True if approved, false otherwise.
+   */
+  event SetApproval(address _user, address _sender, bool _status);
+
+  /*///////////////////////////////////////////////////////////////
+                              VARIABLES
+  //////////////////////////////////////////////////////////////*/
+
+  /**
+   * @notice Checks if a user has whitelisted the sender address.
+   * @param _user The address of the user whose whitelist is being checked.
+   * @param _sender The address of the sender to check against the user's whitelist.
+   * @return _status True if approved, false otherwise.
+   */
+  function whitelist(address _user, address _sender) external view returns (bool _status);
+
+  /*///////////////////////////////////////////////////////////////
+                              LOGIC
+  //////////////////////////////////////////////////////////////*/
+
+  /**
+   * @notice Sets the approval status for a given sender address.
+   * @param _allowedSender The address of the sender to be approved or disapproved.
+   * @param _status True if approved, false otherwise.
+   */
+  function setSenderApproval(address _allowedSender, bool _status) external;
+}