#7690 Add plain server chassis - for custom chassis composition

[planetf1]

Description

Adds the 'plain' server chassis into the server-chass-spring artifact as per issue #7690

This can be consumed via

    implementation "org.odpi.egeria:server-chassis-spring:${egeriaversion}:plain"

Related Issue(s)

Fixes #7690

Testing

1. Apply PR [Enhancement] Add 'plain' server chassis jar into published artifact #7690 into core egeria & rebuild with ./gradlew build publishToMavenLocal
2. Build this project with ./gradlew clean build
3. Go to healthcheck/build/libs
4. cp ../../src/main/resources/*p12 .
5. jar ./healthcheck.jar

This will launch the chassis. Then the new API can be verified with

 egeria-cloudnative git:(main) ✗ http --verify=no --pretty=format GET https://localhost:9443/open-metadata/healthcheck/platform/health
HTTP/1.1 200
Connection: keep-alive
Content-Length: 19
Content-Type: text/plain;charset=UTF-8
Date: Wed, 24 May 2023 12:41:41 GMT
Keep-Alive: timeout=60

Platform is healthy

Release Notes & Documentation

Additional notes

[mandy-chessell]

"plain" is not very descriptive . It would be easier to use if the name matched the build option - eg server-chassis-only

Misunderstanding of purpose of change

[planetf1]

Thanks @mandy-chessell will be useful for prototyping.

The 'plain' designation is build technical, and spring-boot default. It refers to only the java code contained within this module, not any dependencies. It isn't even runnable in any way.

• A similar pattern may be useful in other maven artifacts where we currently build an uber jar, as it facilitates external composition
• The same approach of using classifiers can be used for any purpose - so we could define useful combinations of dependencies that provide different variations such as 'minimal-chassis' or 'integration-chassis' if we wanted, labelling each with a different classifier. Though they would all go into the same artifact which would get bigger. For the HMS connector we have a need to build variants for different levels of HMS
• An alternative to classifiers is to publish to different artifacts. Which to use may depend on how similar or different the jar/file/archive is.