# IFastUpdater

> Interface for updating block-latency feeds.

> For the complete documentation index, see [llms.txt](/llms.txt). Markdown versions of documentation pages are available by appending `.md` to the page URL.

Source: https://dev.flare.network/ftso/solidity-reference/IFastUpdater

Interface for updating block-latency feeds.

Sourced from `IFastUpdater.sol` on [GitHub](https://github.com/flare-foundation/flare-smart-contracts-v2/blob/main/contracts/userInterfaces/IFastUpdater.sol).

## Functions[​](#functions "Direct link to Functions")

### blockScoreCutoff[​](#blockscorecutoff "Direct link to 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[​](#parameters "Direct link to Parameters")

-   `_blockNum`: The block for which the cutoff is requested.

#### Returns[​](#returns "Direct link to 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[​](#currentrewardepochid "Direct link to currentRewardEpochId")

Id of the current reward epoch.

```
function currentRewardEpochId() external view returns (    uint24);
```

### currentScoreCutoff[​](#currentscorecutoff "Direct link to currentScoreCutoff")

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

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

#### Returns[​](#returns-1 "Direct link to 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[​](#currentsortitionweight "Direct link to currentSortitionWeight")

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

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

#### Parameters[​](#parameters-1 "Direct link to 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[​](#returns-2 "Direct link to 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[​](#fetchallcurrentfeeds "Direct link to fetchAllCurrentFeeds")

Public access to the stored data of all feeds.

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

#### Returns[​](#returns-3 "Direct link to 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[​](#fetchcurrentfeeds "Direct link to 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[​](#parameters-2 "Direct link to Parameters")

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

#### Returns[​](#returns-4 "Direct link to 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[​](#numberofupdates "Direct link to 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[​](#parameters-3 "Direct link to Parameters")

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

#### Returns[​](#returns-5 "Direct link to 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[​](#numberofupdatesinblock "Direct link to 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[​](#parameters-4 "Direct link to Parameters")

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

#### Returns[​](#returns-6 "Direct link to Returns")

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

### submissionWindow[​](#submissionwindow "Direct link to 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[​](#submitupdates "Direct link to submitUpdates")

The entry point for providers to submit an update transaction.

```
function submitUpdates(    struct IFastUpdater.FastUpdates _updates) external;
```

#### Parameters[​](#parameters-5 "Direct link to 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[​](#events "Direct link to Events")

### FastUpdateFeedRemoved[​](#fastupdatefeedremoved "Direct link to FastUpdateFeedRemoved")

Event emitted when a feed is removed.

```
event FastUpdateFeedRemoved(    uint256 index)
```

### FastUpdateFeedReset[​](#fastupdatefeedreset "Direct link to FastUpdateFeedReset")

Event emitted when a feed is added or reset.

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

### FastUpdateFeeds[​](#fastupdatefeeds "Direct link to 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[​](#fastupdatefeedssubmitted "Direct link to FastUpdateFeedsSubmitted")

Event emitted when a new set of updates is submitted.

```
event FastUpdateFeedsSubmitted(    uint32 votingRoundId,    address signingPolicyAddress)
```

## Structures[​](#structures "Direct link to Structures")

### FastUpdates[​](#fastupdates "Direct link to FastUpdates")

Fast update structure

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

### Signature[​](#signature "Direct link to Signature")

Signature structure

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