In order to ensure backwards compatibility, PBTS should be enabled via consensus params.

In #2018 MedianTime was removed per the original work in tendermint/tendermint#7382. This does not consider that PBTS can be adopted in existing chains, with blocks produced and that need to be verified using the BFT Time algorithm.

Specification

• Addressed by spec(consensus): update description of consensus parameters for PBTS #2415 (depends on 2376 below)
  • Specify the transition from BFT Time to PBTS via consensus parameter
    • Add it to spec/consensus/time.md
  • Update documentation of FeatureParams, remove references to ABCIParams

Documentation

• Addressed by docs(pbts): documentation for PBTS-related consensus parameters #2376
  • Update ADR with the adopted solution: docs: ADR-112 Proposer-Based Timestamps #2223
  • Update the PBTS documentation accordingly
  • Add to the PBTS documentation the workaround for transitioning to PBTS proposed in the ADR (see this comment).

Implementation

• "Rescue" code removed by cherry-picks:
  • PBTS: Restore state.MedianTime and affected call sites (block creation and validation) #2203
    • revert(pbts): revert removal of BFT Time related functions #2205
  • PBTS: Restore and adapt voteTime() consensus method accordingly #2204
    • revert(pbts): revert removal of BFT Time related functions #2205
  • refactor!: moved MedianTime out of internal folder #2397
  • Adapt calls to the construction types.NewProposal to accept a timestamp (see comment)
    • This is not needed, as in if we didn't update them yet, compilation errors and test failing would be observed
• Introduce and implement consensus param to enable PBTS
  • PBTS: Introduce consensus param to enable PBTS, along with all validation to update it #2197
    • feat(pbts): Update consensus params to include pbts enabled #2231
    • Move vote_extension_enable_height to FeatureParams #2325
  • PBTS: Address latest comments on #2231 #2326
  • State store should be able to unmarshal the old version of ConsensusParams protobuf from the DB #2438

Testing

• PBTS should be enabled by default in consensus test units #2324
  • test(consensus): PBTS should be enabled by default in test units #2329
• tests: add unit tests to check the activation of PBTS #2393
  • test(consensus): test enabling PBTS at a given height #2404 (depends on 2339 above)
• e2e: support PBTS enable param #2227