eclair/docs/release-notes/eclair-vnext.md

Eclair vnext

Major changes

Alternate strategy to avoid mass force-close of channels in certain cases

The default strategy, when an unhandled exception or internal error happens, is to locally force-close the channel. Not only is there a delay before the channel balance gets refunded, but if the exception was due to some misconfiguration or bug in eclair that affects all channels, we risk force-closing all channels.

This is why an alternative behavior is to simply log an error and stop the node. Note that if you don't closely monitor your node, there is a risk that your peers take advantage of the downtime to try and cheat by publishing a revoked commitment. Additionally, while there is no known way of triggering an internal error in eclair from the outside, there may very well be a bug that allows just that, which could be used as a way to remotely stop the node (with the default behavior, it would "only" cause a local force-close of the channel).

Separate log for important notifications

Eclair added a new log file (notifications.log) for important notifications that require an action from the node operator. Node operators should watch this file very regularly.

An event is also sent to the event stream for every such notification. This lets plugins notify the node operator via external systems (push notifications, email, etc).

Initial support for onion messages

Eclair now supports the feature option_onion_messages. If this feature is enabled, eclair will relay onion messages. It can also send onion messages with the sendonionmessage API. Messages sent to Eclair will be ignored.

API changes

Timestamps

All timestamps are now returned as an object with two attributes:

• iso: ISO-8601 format with GMT time zone. Precision may be second or millisecond depending on the timestamp.
• unix: seconds since epoch formats (seconds since epoch). Precision is always second.

Examples:

• second-precision timestamp:
  • before:

  {
    "timestamp": 1633357961
  }
  

  • after

  {
    "timestamp": {
      "iso": "2021-10-04T14:32:41Z",
      "unix": 1633357961
    }
  }
  

• milli-second precision timestamp:
  • before:

  {
    "timestamp": 1633357961456
  }
  

  • after (note how the unix format is in second precision):

  {
    "timestamp": {
      "iso": "2021-10-04T14:32:41.456Z",
      "unix": 1633357961
    }
  }
  

Sending onion messages

You can now send onion messages with sendonionmessage. It expects --route a list of nodeId to send the message through, the last one being the recipient, and --content the content of the message as an encoded TLV stream in hexadecimal. It also accepts --pathId as an encoded TLV stream in hexadecimal. Sending to a blinded route (as a reply to a previous message) is not supported.

This release contains many other API updates:

• deleteinvoice allows you to remove unpaid invoices (#1984)
• findroute, findroutetonode and findroutebetweennodes supports new output format full (#1969)
• findroute, findroutetonode and findroutebetweennodes now accept --ignoreNodeIds to specify nodes you want to be ignored in path-finding (#1969)
• findroute, findroutetonode and findroutebetweennodes now accept --ignoreShortChannelIds to specify channels you want to be ignored in path-finding (#1969)
• findroute, findroutetonode and findroutebetweennodes now accept --maxFeeMsat to specify an upper bound of fees (#1969)
• getsentinfo output includes failedNode field for all failed routes

Have a look at our API documentation for more details.

Balance

The detailed balance json format has been slightly updated for channels in state normal and shutdown, and closing.

Amounts corresponding to incoming htlcs for which we knew the preimage were previously included in toLocal, they are now grouped with outgoing htlcs amounts and the field has been renamed from htlcOut to htlcs.

Miscellaneous improvements and bug fixes

• Eclair now supports cookie authentication for Bitcoin Core RPC (#1986)

Verifying signatures

You will need gpg and our release signing key 7A73FE77DE2C4027. Note that you can get it:

• from our website: https://acinq.co/pgp/drouinf.asc
• from github user @sstone, a committer on eclair: https://api.github.com/users/sstone/gpg_keys

To import our signing key:

$ gpg --import drouinf.asc

To verify the release file checksums and signatures:

$ gpg -d SHA256SUMS.asc > SHA256SUMS.stripped
$ sha256sum -c SHA256SUMS.stripped

Building

Eclair builds are deterministic. To reproduce our builds, please use the following environment (*):

• Ubuntu 20.04
• AdoptOpenJDK 11.0.6
• Maven 3.8.1

Use the following command to generate the eclair-node package:

mvn clean install -DskipTests

That should generate eclair-node/target/eclair-node-<version>-XXXXXXX-bin.zip with sha256 checksums that match the one we provide and sign in SHA256SUMS.asc

(*) You may be able to build the exact same artefacts with other operating systems or versions of JDK 11, we have not tried everything.

Upgrading

This release is fully compatible with previous eclair versions. You don't need to close your channels, just stop eclair, upgrade and restart.

Changelog

<fill this section when publishing the release with git log v0.6.2... --format=oneline --reverse>