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IFastUpdater

Interface for updating block-latency feeds.

Sourced from IFastUpdater.sol on GitHub.

Functions​

blockScoreCutoff​

Informational getter concerning the eligibility criterion for being chosen by sortition in a given block.

function blockScoreCutoff(
    uint256 _blockNum
) external view returns (
    uint256 _cutoff
);

Parameters​

  • _blockNum: The block for which the cutoff is requested.

Returns​

  • _cutoff: The upper endpoint of the acceptable range of "scores" that providers generate for sortition. A score below the cutoff indicates eligibility to submit updates in the present sortition round.

currentRewardEpochId​

Id of the current reward epoch.

function currentRewardEpochId(
) external view returns (
    uint24
);

currentScoreCutoff​

Informational getter concerning the eligibility criterion for being chosen by sortition.

function currentScoreCutoff(
) external view returns (
    uint256 _cutoff
);

Returns​

  • _cutoff: The upper endpoint of the acceptable range of "scores" that providers generate for sortition. A score below the cutoff indicates eligibility to submit updates in the present sortition round.

currentSortitionWeight​

Informational getter concerning a provider's likelihood of being chosen by sortition.

function currentSortitionWeight(
    address _signingPolicyAddress
) external view returns (
    uint256 _weight
);

Parameters​

  • _signingPolicyAddress: The signing policy address of the specified provider. This is different from the sender of an update transaction, due to the signature included in the FastUpdates type.

Returns​

  • _weight: The specified provider's weight for sortition purposes. This is derived from the provider's delegation weight for the FTSO, but rescaled against a fixed number of "virtual providers", indicating how many potential updates a single provider may make in a sortition round.

fetchAllCurrentFeeds​

Public access to the stored data of all feeds.

function fetchAllCurrentFeeds(
) external view returns (
    bytes21[] _feedIds,
    uint256[] _feeds,
    int8[] _decimals,
    uint64 _timestamp
);

Returns​

  • _feedIds: The list of feed ids.
  • _feeds: The list of feeds.
  • _decimals: The list of decimal places for feeds.
  • _timestamp: The timestamp of the last update.

fetchCurrentFeeds​

Public access to the stored data of each feed, allowing controlled batch access to the lengthy complete data. Feeds should be sorted for better performance.

function fetchCurrentFeeds(
    uint256[] _indices
) external view returns (
    uint256[] _feeds,
    int8[] _decimals,
    uint64 _timestamp
);

Parameters​

  • _indices: Index numbers of the feeds for which data should be returned, corresponding to feedIds in the FastUpdatesConfiguration contract.

Returns​

  • _feeds: The list of data for the requested feeds, in the same order as the feed indices were given (which may not be their sorted order).
  • _decimals: The list of decimal places for the requested feeds, in the same order as the feed indices were given (which may not be their sorted order).
  • _timestamp: The timestamp of the last update.

numberOfUpdates​

The number of updates submitted in each block for the last _historySize blocks (up to MAX_BLOCKS_HISTORY).

function numberOfUpdates(
    uint256 _historySize
) external view returns (
    uint256[] _noOfUpdates
);

Parameters​

  • _historySize: The number of blocks for which the number of updates should be returned.

Returns​

  • _noOfUpdates: The number of updates submitted in each block for the last _historySize blocks. The array is ordered from the current block to the oldest block.

numberOfUpdatesInBlock​

The number of updates submitted in a block - available only for the last MAX_BLOCKS_HISTORY blocks.

function numberOfUpdatesInBlock(
    uint256 _blockNumber
) external view returns (
    uint256 _noOfUpdates
);

Parameters​

  • _blockNumber: The block number for which the number of updates should be returned.

Returns​

  • _noOfUpdates: The number of updates submitted in the specified block.

submissionWindow​

The submission window is a number of blocks forming a "grace period" after a round of sortition starts, during which providers may submit updates for that round. In other words, each block starts a new round of sortition and that round lasts submissionWindow blocks.

function submissionWindow(
) external view returns (
    uint8
);

submitUpdates​

The entry point for providers to submit an update transaction.

function submitUpdates(
    struct IFastUpdater.FastUpdates _updates
) external;

Parameters​

  • _updates: Data of an update transaction, which in addition to the actual list of updates, includes the sortition credential proving the provider's eligibility to make updates in the also-included sortition round, as well as a signature allowing a single registered provider to submit from multiple EVM accounts.

Events​

FastUpdateFeedRemoved​

Event emitted when a feed is removed.

event FastUpdateFeedRemoved(
    uint256 index
)

FastUpdateFeedReset​

Event emitted when a feed is added or reset.

event FastUpdateFeedReset(
    uint256 votingRoundId,
    uint256 index,
    bytes21 id,
    uint256 value,
    int8 decimals
)

FastUpdateFeeds​

Event emitted at the start of a new voting epoch - current feeds' values and decimals.

event FastUpdateFeeds(
    uint256 votingEpochId,
    uint256[] feeds,
    int8[] decimals
)

FastUpdateFeedsSubmitted​

Event emitted when a new set of updates is submitted.

event FastUpdateFeedsSubmitted(
    uint32 votingRoundId,
    address signingPolicyAddress
)

Structures​

FastUpdates​

Fast update structure

struct FastUpdates {
  uint256 sortitionBlock;
  struct SortitionCredential sortitionCredential;
  bytes deltas;
  struct IFastUpdater.Signature signature;
}

Signature​

Signature structure

struct Signature {
  uint8 v;
  bytes32 r;
  bytes32 s;
}