Ashley
87cc216774
* Made a start * So the proof between authority set is phragmen one, this is crazy big, or is there some signing of the result : that is the storage key, damn? * ok getting from header digest seems doable. * for testing * get set id from storage directly (should use runtime to handler change). * move test to init * correct auth key * fix iteration * Correct proof content * actually update block number. * actually check last justif against its header * justification relation to new authorities through header hash check is needed here. This assumes the hash from header is calculated. * Few changes * Connected up cheme's branch * Clean up * Move things around a bit so that adding the grandpa warp sync request response protocol happens in the node code * Nits * Changes to comments * Cheme changes * Remove todos and test compile. * Rename _authority_ related proof function to _warp_sync_ . * Update client/grandpa-warp-sync/src/lib.rs quick fix * Put the warp sync request response protocol behind a feature flag because we dont' need it on a light client. * Update client/grandpa-warp-sync/src/lib.rs Quick fix * Update Cargo.lock * Adding test, comment on limitation related to 'delay', this could be implemented but with a cost. * Set between a delay override last fragment. * Check for pending authority set change at start. * adjust index * custom cache is not a good idea. * Use a simple cache instead. * restore broken indentation * Address crate rename * Merge conflict badly resolved, sorry Co-authored-by: cheme <emericchevalier.pro@gmail.com> Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>
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