tree 0d8ade7c95d54a576d88e53fb5e8ca9ee76c8f29
parent 5456a3c4f14f7f73eb49dbfbb3de0bc009c970fe
author Serge Bazanski <serge@monogon.tech> 1677679047 +0000
committer Serge Bazanski <serge@monogon.tech> 1678985728 +0000

m/pkg/event: make type-safe

This is a fairly large change which makes use of Go type parameters
(“generics”) to make the event library (and its memory/etcd
implementations) type safe.

Since we now have the event.Value interface strongly typed, we also move
options which were implementation-specific (like BacklogOnly)
to be part of that interface, instead of the previously type-asserted
specific implementations. Use of options that are not handled by a
particular implementation is a runtime error. Expressing this in the
type system is probably not worth the effort.

We also implement Filter to allow offloading some of the functionality previously implemented in type assertion wrappers into the library itself.

In the end, this ends up removing a bunch of type assertion code, at
the cost of a fairly sweeping change. Unfortunately, some of this is due
to IntelliJ suddenly deciding to reformat comments.

Change-Id: I1ca6d93db1b5c4055a21af3fb9e5e3d425c0d86e
Reviewed-on: https://review.monogon.dev/c/monogon/+/1322
Tested-by: Jenkins CI
Reviewed-by: Leopold Schabel <leo@monogon.tech>