Upgrade to cardano-node 8

[ch1bo]

Why

We are still using cardano node 1.35.7 while there had been newer, mainnet compatible node releases.

Upgrading to cardano-node 8.x is desirable as it allows integration with Mithril to bootstrap a cardano-node.

What

• At least one cardano-node 8.x version is supported by the hydra-node
  • The one or multiple kown-to-work versions is added to the changelog
• A breaking change of Hydra scripts is acceptable
• JSON encoding of objects on the Hydra API may have breaking changes
  • e.g. due to transitive cardano-ledger update
  • All API changes are documented
  • When changed, the cardanonical JSON schema shall be used as new reference
• Determine and clarify whether the overall Tx CBOR has changed in a non-backward compatible way, i.e. can previously working transaction cbors still be sent through NewTx

How

https://github.com/input-output-hk/hydra/tree/ch1bo/use-cardano-node-8

https://github.com/input-output-hk/hydra/tree/ch1bo/update-dependencies

When updating to 8.1.2 while keeping the same (cardano-api 1.35.0-rc4) we had problems:

• The api tries NodeToClientV_15 which seems to have been broken (but was never released). Querying the tip (which uses chain sync) errors.
• When overriding to use NodeToClientV_14, the chain sync works, but the local state query results in errors:

MuxError MuxBearerClosed "<socket: 40> closed when reading data, waiting on next header True"

Asked for more information on the NodeToClient API situation in slack.

Might need to bite the bullet of upgrading cardano-api and with that cardano-ledger throughout the repo instead..

---

Maybe have a collaboratively maintained json instance repository with ogmios: https://github.com/CardanoSolutions/cardanonical

https://github.com/CardanoSolutions/cardanonical/blob/main/cardano.json holds a quite complete json schema with all kinds of Cardano entities (as used by ogmios 6)

• Use that json schema in our API
• Upstream anything missing
• Contribute a haskell implementation of encoders / decoders to https://github.com/CardanoSolutions/cardanonical
  • ogmios contains lots of encoders
  • kupo contains lots of decoders

[ch1bo]

We ran into this problem: IntersectMBO/plutus#5460