Event Refactor

[edward-swirldslabs]

Notes:

• the target event structure is documented here
• events cross upgrade boundaries, so while making changes we will need to be able to deserialize previous version events as well as being able to serialize them to the exact same bytes (this is needed to validate the hash of the event)
• a good way to manage this migration is to have separate fields for protobuf objects
• once the refactor is done, a SelfSerializable will wrap a protobuf event to support migration. once the migration is complete, we can remove that wrapper
• as far as we know, no one is consuming the consensus event stream, so making changes to it is not a problem
• due to current challenges, all protobuf definitions will be in the same module, platform and services

End goals:

• Apps consume all required protobuf records (payloads, core data, signature)
• Gossip (& PCES) protobuf events
• Double hash payloads when hashing an event
• Cleanup internal event structure

Discussion and planning

Beta Give feedback

1. Discuss: platform/app transaction definition #11387
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2. Discuss: demo app transaction sigs #11384
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3. Finalize event structure and lifecycle #11383
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4. Discuss: consensus event stream during event refactor #11386
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5. Discuss: common protobuf definitions #11388
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6. Finalize protobuf plan

Preparation

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1. Event building/mocking in unit tests #11389
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2. Add dependency from platform-core to protobufs #11764
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3. Create a JMH serialization test #11864
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4. Apps should start using transaction protobuf #11862
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5. Add migration mainnet event test #12021
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6. Create JHM test with double hashing of payloads

Transaction

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1. Create protobuf definitions for event payloads (transactions) #12210
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2. Remove usage of com.swirlds.common.crypto.Signature.verifySignature() #12214
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3. Add signature support to PBJ #12331
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4. Start using protobuf state signature #12589
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5. Conform to PBJ interface for StateSignatureTransaction #12292
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6. Update protobuf payload definitions #12420
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7. Refactor transactions #12551
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8. remove epochHash from StateSignaturePayload #12847
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9. Test apps handle protobuf payloads #12850
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10. Hedera handle protobufs #12885
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11. Remove raw byte[] from transaction #13399
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Event

Beta Give feedback

1. Create protobuf definitions for events #12473
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2. Remove CES CLI commands #12947
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3. Create consensus data protobuf #12982
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4. Remove legacy serialization #12996
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5. Repurpose BaseEventHashedData #13172
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6. CES should consume consensus rounds #13238
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7. All apps should use PBJ semantic version #13344
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8. Put PBJ consensus data into GossipEvent #13308
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9. Put GossipEvent inside ConsensusRound instead of EventImpl
10. Decuople event hashing from serialization
11. Decouple CES serialization from event structure
12. EventImpl should be exposed to only consensus and GUI
13. Migrate PCES to protobuf
14. Add more PBJ support for Signatures #13015
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15. Use Bytes for event signatures #13139
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16. Revert removal of CES info command #13000
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17. Hash should become immutable #12456
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18. Use protobuf event descriptors #13138
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19. Make com.swirlds.common.crypto.Signature immutable
20. Remove Transaction.getContents()
21. Remove usage of GossipEvent.getHashedData Part-1 #13568
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Misc tasks

Beta Give feedback

1. Event additions and refactor #5224
   Feature Enhancement Tech Debt Reduced +2
   

   
2. Make event.softwareVersion @NonNull #11300
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3. Delete UnhashedEventData
4. Disentangle Shadowgraph from Consensus #10978
   5 of 5
   Epic +1
   
5. Remove PlatformEvent::getOtherId #12464
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6. Delete SimpleEvent #12898
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7. Remove PlatformEvent #12959
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