Files
lambda/internal/plugins/debug.go
M.V. Hutz 1974ad582f refactor: move event system to reducer, remove engine package (#32)
## Description

This PR completes the MVC-inspired refactoring by moving the event system from the engine into the reducer.
The engine package is now removed entirely, as the reducer handles both reduction logic and lifecycle events.

- Add `pkg/reducer/events.go` with `StartEvent`, `StepEvent`, and `StopEvent`.
- Extend `Reducer` interface to embed `Emitter[Event]` and add `Expression()` method.
- Update `NormalOrderReducer` to embed `BaseEmitter` and emit lifecycle events during reduction.
- Update all plugins to attach to `Reducer` instead of `Engine`.
- Remove `internal/engine` package entirely.
- Add `Off()` method to `BaseEmitter` to complete the `Emitter` interface.
- Fix `Emitter.On` signature to use generic type `E` instead of `string`.

### Decisions

- The `Reducer` interface now combines reduction logic with event emission, making it the single orchestration point.
- Plugins attach directly to the reducer, simplifying the architecture.
- The `Expression()` method on `Reducer` provides access to current state for plugins.

## Benefits

- Simpler architecture with one fewer abstraction layer.
- Plugins are now mode-agnostic - they work with any `Reducer` implementation.
- Cleaner separation: reducers handle reduction, plugins observe via events.
- Easier to add new evaluation modes - just implement `Reducer` with embedded emitter.

## Checklist

- [x] Code follows conventional commit format.
- [x] Branch follows naming convention (`<type>/<description>`).
- [x] Tests pass (if applicable).
- [ ] Documentation updated (if applicable).

Reviewed-on: #32
Co-authored-by: M.V. Hutz <git@maximhutz.me>
Co-committed-by: M.V. Hutz <git@maximhutz.me>
2026-01-17 00:27:36 +00:00

24 lines
396 B
Go

package plugins
import (
"log/slog"
"git.maximhutz.com/max/lambda/pkg/reducer"
)
type Logs struct {
logger *slog.Logger
reducer reducer.Reducer
}
func NewLogs(logger *slog.Logger, r reducer.Reducer) *Logs {
plugin := &Logs{logger, r}
r.On(reducer.StepEvent, plugin.Step)
return plugin
}
func (t *Logs) Step() {
t.logger.Info("reduction", "tree", t.reducer.Expression().String())
}