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Upgradeable

An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy. A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing UUPSUpgradeable with a custom implementation of upgrades. The {authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism. _Available since v4.1.

Methods​

proxiableUUID​

function proxiableUUID() external view returns (bytes32)

Implementation of the ERC1822 {proxiableUUID} function. This returns the storage slot used by the implementation. It is used to validate that the this implementation remains valid after an upgrade. IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this function revert if invoked through a proxy. This is guaranteed by the notDelegated modifier.

Returns​

NameTypeDescription
_0bytes32undefined

upgradeTo​

function upgradeTo(address newImplementation) external nonpayable

Upgrade the implementation of the proxy to newImplementation. Calls {_authorizeUpgrade}. Emits an {Upgraded} event.

Parameters​

NameTypeDescription
newImplementationaddressundefined

upgradeToAndCall​

function upgradeToAndCall(address newImplementation, bytes data) external payable

Upgrade the implementation of the proxy to newImplementation, and subsequently execute the function call encoded in data. Calls {_authorizeUpgrade}. Emits an {Upgraded} event.

Parameters​

NameTypeDescription
newImplementationaddressundefined
databytesundefined

Events​

AdminChanged​

event AdminChanged(address previousAdmin, address newAdmin)

Parameters​

NameTypeDescription
previousAdminaddressundefined
newAdminaddressundefined

BeaconUpgraded​

event BeaconUpgraded(address indexed beacon)

Parameters​

NameTypeDescription
beacon indexedaddressundefined

Upgraded​

event Upgraded(address indexed implementation)

Parameters​

NameTypeDescription
implementation indexedaddressundefined