Oracle

Initialization

constructor

constructor(address to)

Description

The constructor initializes the smart contract and sets the default roles. It also transfers ownership to the specified address and calculates the domain separator for EIP-712 signatures.

Parameters

Name	Type	Description
to	address	The address to which ownership of the contract will be transferred during initialization.

Write Methods

updateObservation

function updateObservation(
    uint144 value, 
    address[] calldata signers, 
    uint256[] calldata deadline,
    uint8[] calldata v, 
    bytes32[] calldata r, 
    bytes32[] calldata s
) external

Description

The updateObservation function is used to update the Oracle price if the following conditions are satisfied

• All signers must reach a consensus and produce a signed message containing the same price observation

• Each signed message must be created by a different signer

• Each signed message must have a deadline not already passed

• The number of signers is equal to or greater than the signer threshold

• The cooldown period has elapsed since the last update

• The percentage change between the old and new price observation is within an allowed delta

Parameters

Name	Type	Description
value	uint144	The new observation value to be updated
signers	address[]	An array of addresses representing the signers involved in the update
deadline	uint256[]	An array of deadlines corresponding to each signatures
v	uint8[]	An array of the 'v' components of the ECDSA signatures
r	bytes32[]	An array of the 'r' components of the ECDSA signatures
s	bytes32[]	An array of the s' components of the ECDSA signatures

Emits

LogUpdateObservation

freeze

function freeze() external onlyOperators

Description

The freeze function is an external function that allows designated operators to freeze the contract in case of emergency.

Emits

LogFrozenChanged

unfreeze

function unfreeze() external onlyOwner

Description

The unfreezefunction is an external function that allows the contract owner operators to unfreeze the contract to resume normal operativity.

Emits

LogFrozenChanged

setMaximumDeltaPercentage

function setMaximumDeltaPercentage(
    uint32 maximumDeltaPercentage
) external onlyOwner

Description

The setMaximumDeltaPercentage function is an external function that allows the owner of the contract to set the maximum allowed delta percentage for updates to the price observation.

Parameters

Name	Type	Description
maximumDeltaPercentage	uint32	The new maximum allowed delta percentage for updates

Emits

LogMaxDeltaPercentageChanged

setThreshold

function setThreshold(uint8 threshold) external onlyOwner

Description

The setThreshold function is an external function that allows the owner of the contract to set the minimum required number of signers for updates to the observation state.

Parameters

Name	Type	Description
theshold	uint8	The new minimum required number of signers

Emit

LogSignerThresholdChanged

View Methods

PRECISION

uint256 public constant PRECISION

Description

The precision used by the contract to handle the observation value

HEARTBEAT

uint256 public constant HEARTBEAT

Description

The number of seconds the latest price observation is considered valid and up to date

get

function get(bytes memory) public view override returns (bool, uint256)

Description

The get function is a public view function that allows external callers to retrieve information about the current observation state stored in the contract. It returns a boolean indicating the validity of the observation and the actual observation value.

Parameters

Name	Type	Description
*	bytes	The function does not take any input parameters

Returns

Name	Type	Description
isValid	bool	If true the observation has been updated within HEARTBEAT seconds
observation	uint256	Latest price observation

Events

LogUpdateObservation

event LogUpdateObservation(
    uint256 timestamp,
    uint144 observation
)

Parameters

Name	Type	Index?
timestamp	uint256	No
observation	uint144	No

LogFrozenChanged

event LogFrozenChanged(
    uint256 timestamp,
    uint8 frozen
)

Parameters

Name	Type	Index?
timestamp	uint256	No
frozen	uint8	No

LogMaxDeltaPercentageChanged

event LogMaxDeltaPercentageChanged(
  uint256 timestamp,
  uint32 maxDeltaPercentage
)

Parameters

Name	Type	Index?
timestamp	uint256	No
maxDeltaPercentage	uint32	No

LogSignerThresholdChanged

event LogSignerThresholdChanged(
    uint256 timestamp, 
    uint8 signerThreshold
)

Parameters

Name	Type	Index?
timestamp	uint256	No
signerThreshold	uint8	No