Initialization

How to Initialize Non-Upgradeable Plugins

Every plugin should receive and store the address of the DAO it is associated with upon initialization. This is how the plugin will be able to interact with the DAO that has installed it.

In addition, your plugin implementation might want to introduce other storage variables that should be initialized immediately after the contract was created. For example, in the SimpleAdmin plugin example (which sets one address as the full admin of the DAO), we'd want to store the admin address.

contract SimpleAdmin is Plugin {
  address public admin;
}

The way we set up the plugin's initialize() function depends on the plugin type selected. To review plugin types in depth, check out our guide here.

Additionally, the way we deploy our contracts is directly correlated with how they're initialized. For Non-Upgradeable Plugins, there's two ways in which we can deploy our plugin:

• Deployment via Solidity's new keyword, OR
• Deployment via the Minimal Proxy Pattern

Option A: Deployment via Solidity's new Keyword

To instantiate the contract via Solidity's new keyword, you should inherit from the Plugin Base Template Aragon created. You can find it here.

In this case, the compiler will force you to write a constructor function calling the Plugin parent constructor and provide it with a contract of type IDAO. Inside the constructor, you might want to initialize the storage variables that you have added yourself, such as the admin address in the example below.

// SPDX-License-Identifier: AGPL-3.0-or-later
pragma solidity 0.8.21;

import {Plugin, IDAO} from '@aragon/osx/core/plugin/Plugin.sol';

contract SimpleAdmin is Plugin {
  address public immutable admin;

  /// @notice Initializes the contract.
  /// @param _dao The associated DAO.
  /// @param _admin The address of the admin.
  constructor(IDAO _dao, address _admin) Plugin(_dao) {
    admin = _admin;
  }
}

note

The admin variable is set as immutable so that it can never be changed. Immutable variables can only be initialized in the constructor.

This type of constructor implementation stores the IDAO _dao reference in the right place. If your plugin is deployed often, which we could expect, we can save significant amounts of gas by deployment through using the minimal proxy pattern.

Option B: Deployment via the Minimal Proxy Pattern

To deploy our plugin via the minimal clones pattern (ERC-1167), you inherit from the PluginCloneable contract introducing the same features as Plugin. The only difference is that you now have to remember to write an initialize function.

// SPDX-License-Identifier: AGPL-3.0-or-later
pragma solidity 0.8.21;

import {PluginCloneable, IDAO} from '@aragon/osx/core/plugin/PluginCloneable.sol';

contract SimpleAdmin is PluginCloneable {
  address public admin;

  /// @notice Initializes the contract.
  /// @param _dao The associated DAO.
  /// @param _admin The address of the admin.
  function initialize(IDAO _dao, address _admin) external initializer {
    __PluginCloneable_init(_dao);
    admin = _admin;
  }
}

We must protect it from being called multiple times by using OpenZeppelin's initializer modifier made available through Initializable and call the internal function __PluginCloneable_init(IDAO _dao) available through the PluginCloneable base contract to store the IDAO _dao reference in the right place.

caution

If you forget calling __PluginCloneable_init(_dao) inside your initialize function, your plugin won't be associated with a DAO and cannot use the DAO's PermissionManager.