Owner Data Module

OwnerStorage​

/** storage-location: erc8042:erc173.owner */
struct OwnerStorage {
  address owner;
}

Functions​

getStorage​

Returns a pointer to the OwnerStorage struct.

function getStorage() pure returns (OwnerStorage storage s);

Returns:

owner​

Get the address of the owner

function owner() view returns (address);

Returns:

requireOwner​

Verify if the message sender is the current diamond owner. Useful for gating specify logic inside your own facets.

function requireOwner() view;

Reverts:

setContractOwner​

Writes the inital owner address to storage and emits OwnershipTransferred(address(0), _initialOwner).

There is no msg.sender or role check performed. Use only from trusted initialization code, or wrap with your own checks in a facet.

function setContractOwner(address _initialOwner);

Parameters:

Events​

OwnershipTransferred

Emitted when the ownership changes. setContractOwner always uses previousOwner == address(0). Transfer facets typically emit with the real previous owner.

Signature:

event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

Errors​

OwnerUnauthorizedAccount

Thrown by requireOwner when msg.sender is not the curent owner. Other owner facets may also revert with this error.

Signature:

error OwnerUnauthorizedAccount();

OwnerAlreadyRenounced

Declared here for shared use (for example renounce flows). This module does not reference it; companion facets may revert with it when ownership was already renounced.

Signature:

error OwnerAlreadyRenounced();

Best Practices​

• Call setContractOwner only from trusted init paths (constructor, one-off setup). For transfers, use OwnerTransferMod.transferOwnership or an equivalent facet so events record the real previous owner.
• Guard external entrypoints with requireOwner() or equivalent before state changes restricted to the owner.

Integration Notes​

OwnerStorage is located at keccak256("erc173.owner") inside the diamond.

All Compose Owner contracts use that slot, so owner() and transfer logic observe the same address.

Last updated:June 5, 2026

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