Ashley
d1ef8507d7
* Initial draft * Add an iterator that helps us get most items * Revert changes to grandpa * Change fields to just be the grandpa authority set and babe epoch changes * Only use the fields we need from the shared authority set * Switch to RPC call * Revert "Only use the fields we need from the shared authority set" This reverts commit 6ede87b0c5fe53f251d7cb45951006a7dc8f9b83. * Add babe_finalized_block_weight from `ashley-improve-sync-state-WIP-loading` * Fix rpc test * Move sync state rpc stuff into sc-sync-state-rpc * Remove as_json_value and remove unwraps from sc-sync-state-rpc * Add clone_inner to SharedAuthoritySet
Integration of the GRANDPA finality gadget into substrate.
This crate is unstable and the API and usage may change.
This crate provides a long-running future that produces finality notifications.
Usage
First, create a block-import wrapper with the block_import function. The
GRANDPA worker needs to be linked together with this block import object, so
a LinkHalf is returned as well. All blocks imported (from network or
consensus or otherwise) must pass through this wrapper, otherwise consensus
is likely to break in unexpected ways.
Next, use the LinkHalf and a local configuration to run_grandpa_voter.
This requires a Network implementation. The returned future should be
driven to completion and will finalize blocks in the background.
Changing authority sets
The rough idea behind changing authority sets in GRANDPA is that at some point, we obtain agreement for some maximum block height that the current set can finalize, and once a block with that height is finalized the next set will pick up finalization from there.
Technically speaking, this would be implemented as a voting rule which says, "if there is a signal for a change in N blocks in block B, only vote on chains with length NUM(B) + N if they contain B". This conditional-inclusion logic is complex to compute because it requires looking arbitrarily far back in the chain.
Instead, we keep track of a list of all signals we've seen so far (across all forks), sorted ascending by the block number they would be applied at. We never vote on chains with number higher than the earliest handoff block number (this is num(signal) + N). When finalizing a block, we either apply or prune any signaled changes based on whether the signaling block is included in the newly-finalized chain.
License: GPL-3.0-or-later WITH Classpath-exception-2.0