Upgrade to Corda 4.x

Challenges

• Corda 4.1 is undergoing QA testing with successive release candidates available in R3's artifactory repository.
• braid - needs to be deployed to a Maven repo. Perhaps should avoid SNAPSHOT releases as they require careful management of local maven caches on both developer and CI runners (both which aggresively cache artifacts).
• networkmap-service will need to have a docker image built and deployed to a reachable repository.
• cordite maven artefacts
• cordite docker image

Proposed solutions

braid

1. Create a branch for corda-4 upgrade from master.

2. Create a branch for corda-3 work from master.

3. Following upgrade, merge corda-4 branch to master.

4. Per RC release, create branch e.g. 4.1.0-RC1 and setup release procedure to deploy to Maven central. This is because network-map-service and cordite have to be able to pull this version.

5. All bug fixes that apply to both corda-3 as well as corda-4 will need to be merged to corda-3 branch and release tags will need to be taken off this branch.

networkmap-service

1. Create a branch for corda-4 upgrade from master. Test that v4 NMS is compatible for Corda/Cordite 3.3.x nodes.
2. Merge to master. This will automatically create a latest edge docker image that is pushed to DockerHub.

cordite

As per braid:

1. Create a branch for corda-4 upgrade from master.
2. Create a branch for corda-3 work from master.
3. Following upgrade, merge corda-4 branch to master.
4. Build Cordite artefacts on master and release SNAPSHOT builds of Cordite to Sonatype maven repo.
5. Also on master continue releasing edge versions.
6. Fix edge network to use the cordite/network-map:edge.

The above will continue until Corda O/S 4.1 is released at which point all RC or edge releases will be formally released.