Randomness Pallet
Table of Contents
Overview
The randomness pallet saves a random seed for each block when it's finalized and allows retrieval of this randomness at a later time. There is a limitation - the randomness is available only after the 81st block of the chain, due to randomness predictability earlier. Currently, the seeds are used for the sealing pipeline's pre-commit and prove commit, in other words generating a replica and proving a sector.
Usage
This pallet exposes the interface to get randomness on-chain for a certain block via the trait primitives_proofs::Randomness
or chain state query pallet_randomness:SeedsMap.
Note that, you can only get a randomness for the current_block - 1 and depending on the configuration, the old randomness seed will be removed after the associated block has passed.
Extrinsics
The pallet does not expose any extrinsics.
Events
The pallet does not emit any events.
Errors
The Randomness Pallet actions can fail with the following errors:
SeedNotAvailable- the seed for the given block number is not available, which means the randomness pallet has not gathered randomness for this block yet.
Constants
The Randomness Pallet has the following constants:
| Name | Description | Value |
|---|---|---|
CleanupInterval | Clean-up interval specified in number of blocks between cleanups. | 1 Day |
SeedAgeLimit | The number of blocks after which the seed is cleaned up. | 30 Days |