0.16.0

Major changes to the transaction representation in the API, more preparations for Conway era and EventSource/EventSink abstractions for streaming plugins.

⚠️ Warning
There are still several known issues, which are explained in the documentation.

Build artifacts

• 📦 Binaries for Linux x86_64 and MacOS ARM64, also attached
• 🐋 Docker image

Hydra Scripts

Transaction IDs to be used as --hydra-scripts-tx-id when running hydra-node on common networks are now also stored in the repository:

• preview: 1f34e4ee2404a5e4fc8ef970b7b8717af34c1a5a22107b82cde79c5d11da93b9
• preprod: 6264cee4d5eab3fb58ab67f3899ecbcc0d7e72732a2d9c1c5d638115db6ca711
• mainnet: 2d52e5787b198daeb280f9de63e5dec126b1843b050e85b1642ff8e47cb6de73

Compatible / tested with

• cardano-node: 8.9.0
• cardano-cli: 8.20.3.0
• mithril: 2412.0

Upgrade instructions

This release contains breaking changes of the persisted data and on-chain scripts. This means that you'll need to apply the following procedure to upgrade all the nodes currently running a head:

1. Close and fanout the head
2. Stop hydra-node
3. Remove persistent files stored in --persistence-dir, in particular server-output, acks and state
4. Upgrade hydra-node to this version
5. Upgrade cardano-node to compatible version (above)
6. Start new hydra-node version with new --hydra-scripts-tx-id (above)
7. Open a new head

Changelog

• BREAKING Hydra scripts changed due to updates in the plutus toolchain:

  • Overall slight increase in script size.
  • 50% less memory usage in close and contest transactions.
  • Slightly less memory usage in abort and may be possible with 6 parties now.

• BREAKING Transaction serialization on hydra-node API and persisted data changed:

  • All transactions are now only serialized as CBOR-encoded envelopes.
  • This was needed to avoid accidentally changing transaction ids between Cardano era transaction formats.
  • See API reference for more details on the format.

• BREAKING Change to the hydra-node logs, monitoring and removal of log-filter executable:

  • Renamed the Event data types to Input and consequently log items like BeginEvent to BeginInput.
  • Changed structure of LogicOutcome entries.
  • Added node-level log entry when an input was DroppedFromQueue.
  • In course of this, the log-filter executable was removed as nobody is actively using it and other off-the-shelf utilities to manipulate structured JSON logs (jq is already quite powerful) are recommended.
  • Renamed prometheus metric hydra_head_events -> hydra_head_inputs.

• Introduce EventSource and EventSink interfaces in hydra-node:

  • These handles can now be used as "extension points" to make the hydra-node store and load its state differently or expose StateEvents to other, external services.
  • Internal refactoring of persistence mechanism as event source and sink in a backward-compatible way.
  • More details can be found in ADR21

• Add metadata to identify Hydra protocol transactions created by hydra-node.

• Provide more details about why a command failed. Added the state of the head logic at the point of failure.

• Fix a bug where the hydra-node would not correctly observe a contest transaction and fail to fanout a head #1260.

• Add contestationDeadline to the HeadIsContested output on the hydra-node API.

• Add --sanchonet option to hydra-cluster binary.

• Enhance hydra-cluster --devnet mode to produce a constant stream of snaphsots by re-spending the sandbox UTxO.

• Reduce cost of transactions submitted by hydra-node by better estimating fees in internal wallet #1315.

• Fix conversion of Conway blocks in hydra-node and hydra-chain-observer. This also includes tests that verify hydra-node working on Conway networks like sanchonet and the hydra-explorer observing heads on sanchonet.

• Fix a bug in the contest observation where contesters were extracted from the
  input instead of the output datum.
  #1266

New Contributors

• @coot made their first contribution in #1300
• @Quantumplation made their first contribution in #1351

Contributors

Contributors: @v0d1ch @abailly-iohk @locallycompact @ffakenz @ch1bo

Full Changelog: 0.15.0...0.16.0