PRICEv1

Price oracle data storage

The friendtech33 Price Oracle contract provides a standard interface for FTW price data against a reserve asset. It also implements a moving average price calculation (same as a TWAP) on the price feed data over a configured duration and observation frequency. The data provided by this contract is used by the friendtech33 Range Operator to perform market operations. The friendtech33 Price Oracle is updated each epoch by the friendtech33 Heart contract.

Methods

INIT

function INIT() external nonpayable

Initialization function for the module

This function is called when the module is installed or upgraded by the kernel.MUST BE GATED BY onlyKernel. Used to encompass any initialization or upgrade logic.

KEYCODE

function KEYCODE() external pure returns (Keycode)

5 byte identifier for a module.

Returns

Name	Type	Description
_0	Keycode	undefined

VERSION

function VERSION() external pure returns (uint8 major, uint8 minor)

Returns which semantic version of a module is being implemented.

Returns

Name	Type	Description
major	uint8	- Major version upgrade indicates breaking change to the interface.
minor	uint8	- Minor version change retains backward-compatible interface.

changeKernel

function changeKernel(contract Kernel newKernel_) external nonpayable

Function used by kernel when migrating to a new kernel.

Parameters

Name	Type	Description
newKernel_	contract Kernel	undefined

changeMovingAverageDuration

function changeMovingAverageDuration(uint48 movingAverageDuration_) external nonpayable

Change the moving average window (duration)

Changing the moving average duration will erase the current observations array and require the initialize function to be called again. Ensure that you have saved the existing data and can re-populate before calling this function.

Parameters

Name	Type	Description
movingAverageDuration_	uint48	- Moving average duration in seconds, must be a multiple of observation frequency

changeObservationFrequency

function changeObservationFrequency(uint48 observationFrequency_) external nonpayable

Change the observation frequency of the moving average (i.e. how often a new observation is taken)

Changing the observation frequency clears existing observation data since it will not be taken at the right time intervals. Ensure that you have saved the existing data and/or can re-populate before calling this function.

Parameters

Name	Type	Description
observationFrequency_	uint48	- Observation frequency in seconds, must be a divisor of the moving average duration

changeUpdateThresholds

function changeUpdateThresholds(uint48 ohmEthUpdateThreshold_, uint48 reserveEthUpdateThreshold_) external nonpayable

Change the update thresholds for the price feeds

The update thresholds should be set based on the update threshold of the chainlink oracles.

Parameters

Name	Type	Description
ohmEthUpdateThreshold_	uint48	- Maximum allowed time between FTW/ETH price feed updates
reserveEthUpdateThreshold_	uint48	- Maximum allowed time between Reserve/ETH price feed updates

cumulativeObs

function cumulativeObs() external view returns (uint256)

Running sum of observations to calculate the moving average price from

See getMovingAverage()

Returns

Name	Type	Description
_0	uint256	undefined

decimals

function decimals() external view returns (uint8)

Number of decimals in the price values provided by the contract.

Returns

Name	Type	Description
_0	uint8	undefined

getCurrentPrice

function getCurrentPrice() external view returns (uint256)

Get the current price of FTW in the Reserve asset from the price feeds

Returns

Name	Type	Description
_0	uint256	undefined

getLastPrice

function getLastPrice() external view returns (uint256)

Get the last stored price observation of FTW in the Reserve asset

Returns

Name	Type	Description
_0	uint256	undefined

getMovingAverage

function getMovingAverage() external view returns (uint256)

Get the moving average of FTW in the Reserve asset over the defined window (see movingAverageDuration and observationFrequency).

Returns

Name	Type	Description
_0	uint256	undefined

initialize

function initialize(uint256[] startObservations_, uint48 lastObservationTime_) external nonpayable

Initialize the price moduleAccess restricted to activated policies

This function must be called after the Price module is deployed to activate it and after updating the observationFrequency or movingAverageDuration (in certain cases) in order for the Price module to function properly.

Parameters

Name	Type	Description
startObservations_	uint256[]	- Array of observations to initialize the moving average with. Must be of length numObservations.
lastObservationTime_	uint48	- Unix timestamp of last observation being provided (in seconds).

initialized

function initialized() external view returns (bool)

Whether the price module is initialized (and therefore active).

Returns

Name	Type	Description
_0	bool	undefined

kernel

function kernel() external view returns (contract Kernel)

Returns

Name	Type	Description
_0	contract Kernel	undefined

lastObservationTime

function lastObservationTime() external view returns (uint48)

Unix timestamp of last observation (in seconds).

Returns

Name	Type	Description
_0	uint48	undefined

movingAverageDuration

function movingAverageDuration() external view returns (uint48)

Duration (in seconds) over which the moving average is calculated.

Returns

Name	Type	Description
_0	uint48	undefined

nextObsIndex

function nextObsIndex() external view returns (uint32)

Index of the next observation to make. The current value at this index is the oldest observation.

Returns

Name	Type	Description
_0	uint32	undefined

numObservations

function numObservations() external view returns (uint32)

Number of observations used in the moving average calculation. Computed from movingAverageDuration / observationFrequency.

Returns

Name	Type	Description
_0	uint32	undefined

observationFrequency

function observationFrequency() external view returns (uint48)

Frequency (in seconds) that observations should be stored.

Returns

Name	Type	Description
_0	uint48	undefined

observations

function observations(uint256) external view returns (uint256)

Array of price observations. Check nextObsIndex to determine latest data point.

Observations are stored in a ring buffer where the moving average is the sum of all observations divided by the number of observations. Observations can be cleared by changing the movingAverageDuration or observationFrequency and must be re-initialized.

Parameters

Name	Type	Description
_0	uint256	undefined

Returns

Name	Type	Description
_0	uint256	undefined

ohmEthPriceFeed

function ohmEthPriceFeed() external view returns (contract AggregatorV2V3Interface)

FTW/ETH price feed

Returns

Name	Type	Description
_0	contract AggregatorV2V3Interface	undefined

ohmEthUpdateThreshold

function ohmEthUpdateThreshold() external view returns (uint48)

Maximum expected time between FTW/ETH price feed updates

Returns

Name	Type	Description
_0	uint48	undefined

reserveEthPriceFeed

function reserveEthPriceFeed() external view returns (contract AggregatorV2V3Interface)

Reserve/ETH price feed

Returns

Name	Type	Description
_0	contract AggregatorV2V3Interface	undefined

reserveEthUpdateThreshold

function reserveEthUpdateThreshold() external view returns (uint48)

Maximum expected time between FTW/ETH price feed updates

Returns

Name	Type	Description
_0	uint48	undefined

updateMovingAverage

function updateMovingAverage() external nonpayable

Trigger an update of the moving average. Permissioned.

This function does not have a time-gating on the observationFrequency on this contract. It is set on the Heart policy contract. The Heart beat frequency should be set to the same value as the observationFrequency.

Events

MovingAverageDurationChanged

event MovingAverageDurationChanged(uint48 movingAverageDuration_)

Parameters

Name	Type	Description
movingAverageDuration_	uint48	undefined

NewObservation

event NewObservation(uint256 timestamp_, uint256 price_, uint256 movingAverage_)

Parameters

Name	Type	Description
timestamp_	uint256	undefined
price_	uint256	undefined
movingAverage_	uint256	undefined

ObservationFrequencyChanged

event ObservationFrequencyChanged(uint48 observationFrequency_)

Parameters

Name	Type	Description
observationFrequency_	uint48	undefined

UpdateThresholdsChanged

event UpdateThresholdsChanged(uint48 ohmEthUpdateThreshold_, uint48 reserveEthUpdateThreshold_)

Parameters

Name	Type	Description
ohmEthUpdateThreshold_	uint48	undefined
reserveEthUpdateThreshold_	uint48	undefined

Errors

KernelAdapter_OnlyKernel

error KernelAdapter_OnlyKernel(address caller_)

Parameters

Name	Type	Description
caller_	address	undefined

Module_PolicyNotPermitted

error Module_PolicyNotPermitted(address policy_)

Parameters

Name	Type	Description
policy_	address	undefined

Price_AlreadyInitialized

error Price_AlreadyInitialized()

Price_BadFeed

error Price_BadFeed(address priceFeed)

Parameters

Name	Type	Description
priceFeed	address	undefined

Price_InvalidParams

error Price_InvalidParams()

Price_NotInitialized

error Price_NotInitialized()