mirrors/tendermint
1
0
Fork 0
mirror of https://github.com/tendermint/tendermint.git synced 2026-04-25 10:10:30 +00:00
Code Issues Packages Projects Releases Wiki Activity

Handle the distinction between 'any' occurrences (*) and 'infinite' occurrences (omega) in the grammar

Browse Source
This commit is contained in:
Sergio Mena
2022-01-13 11:04:38 +01:00
parent 81be4d0d14
commit e3da1bf94a
1 changed files with 18 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
spec/abci++/abci++_tmint_expected_behavior_002_draft.md
View File

@@ -34,20 +34,21 @@ Application design should consider _any_ of these possible sequences.
The following grammar, written in case-sensitive Augmented Backus–Naur form (ABNF, specified
in [IETF rfc7405](https://datatracker.ietf.org/doc/html/rfc7405)), specifies all possible
sequences of calls to ABCI++ across all heights from the genesis block, including recovery runs,
from the point of view of the Application.
sequences of calls to ABCI++, taken by a correct process, across all heights from the genesis block,
including recovery runs, from the point of view of the Application.
```abnf
start = clean-start / recovery
clean-start = init-chain [state-sync] *consensus-height
clean-start = init-chain [state-sync] consensus-exec
state-sync = *state-sync-attempt success-sync info
state-sync-attempt = offer-snapshot *apply-chunk
success-sync = offer-snapshot 1*apply-chunk
recovery = info *consensus-replay *consensus-height
recovery = info *consensus-replay consensus-exec
consensus-replay = decide
consensus-exec = (inf)consensus-height
consensus-height = *consensus-round decide
consensus-round = proposer / non-proposer
@@ -68,8 +69,6 @@ got-vote = %s"<VerifyVoteExtension>"
decide = %s"<FinalizeBlock>"
```
>**TODO** We need to get the grammar reviewed by the people that know block-execution inside out.
>**TODO** Still hesitating... introduce _n_ as total number of validators, so that we can bound the occurrences of
>`got-vote` in a round.
@@ -107,10 +106,10 @@ Let us now examine the grammar line by line, providing further details.
* If the process is starting from scratch, Tendermint first calls `InitChain`, then it may optionally
start a _state-sync_ mechanism to catch up with other processes. Finally, it enters normal
consensus execution, which is a sequence of zero or more consensus heights.
consensus execution.
>```abnf
>clean-start = init-chain [state-sync] *consensus-height
>clean-start = init-chain [state-sync] consensus-exec
>```
* In _state-sync_ mode, Tendermint makes one or more attempts at synchronizing the Application's state.
@@ -129,13 +128,22 @@ Let us now examine the grammar line by line, providing further details.
* In recovery mode, Tendermint first calls `Info` to know from which height it needs to replay decisions
to the Application. To replay a decision, Tendermint simply calls `FinalizeBlock` with the decided
block at that height. After this, Tendermint enters nomal consensus execution: zero or more consensus heights.
block at that height. After this, Tendermint enters nomal consensus execution.
>```abnf
>recovery = info *consensus-replay *consensus-height
>recovery = info *consensus-replay consensus-exec
>consensus-replay = decide
>```
* The non-terminal `consensus-exec` is a key point in this grammar. It is an infinite sequence of
consensus heights. The grammar is thus an
[omega-grammar](https://dl.acm.org/doi/10.5555/2361476.2361481), since it produces infinite
sequences of terminals (i.e., the API calls).
>```abnf
>consensus-exec = (inf)consensus-height
>```
* A consensus height consists of zero or more rounds before deciding via a call to `FinalizeBlock`.
In each round, the sequence of method calls depends on whether the local process is the proposer or not.