eventsourcing/es4j

Problem: impossible to define indices in Scala

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#174 opened on Oct 29, 2016

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Description

According to a report by @bsrk, and subsequent verification, Scala does not support static fields in classes. It does have companion objects, however, since Scala does not consider it a class and it is therefore impossible to specify it in the @Indices(Array(MyEventIndices)) annotation.

Proposed solution: implement a ScalaObjectIndexLoader that will use Scala's own reflection, but other ideas are welcome.

Temporary workaround (for those who need one): write your index definitions in separate Java classes and refer to them in @Indices(...) annotations.

Contributor guide

Research direction
Investigate how Scala companion objects can be registered with the @Indices annotation, possibly by implementing a ScalaObjectIndexLoader using Scala reflection.
Tech stack
javascala
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
ScalaReflection
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40