NgDraw
Angular learning project generated with Angular CLI version 11.0.4.
Deployed here: https://ng-draw.vercel.app/
Conclusions / Lessons / Questions
- In general, despite some superficial/textbook aquaintance with design patterns and the vocabulary around them, I'm inexperienced with actually solving the kinds of problems that come up with OOP design-- how many and what kind abstractions to use, how to divide data and methods up appropritely among them, etc. (For a long time I have worked in a context of global immutable state objects paired with lots of small, pure helper functions with only a couple of "design pattern" ideas sprinkled thinly on top-- an approach that just avoids most of these problems.) That's all to say: open to any and all feedback from you all about the approach I took here; very little invested in thinking anything I've done here makes much sense.
- Singleton services should not depend on one another; this is a single-responsibility principle code smell. Methods which depend on multiple singleton services should probably live in component-scoped services if not components themselves (the latter is what I've done here). I went some ways down a bad path here and had to do a costly refactor to get out of it.
- The Canvas service is probably way too big but I can't think of a good way to break it up that improves as opposed to inhibits readability...
- Immutable data strucures could be a way around the awkward way the observable state is used here--we'd rely on the change-detection system rather than the observable for the scene state--but I'm trying to pick up the observables way of doing things. I suspect the observable-architecture way to go here would be to have the subscription to the scene array flatMap/mergeMap in shape subscriptions such that shape property changes trigger canvas redraws automatically?
- Did my own color picker to experiment with modals, ng-content, layout components. Far from confident that the pattern I'm using makes sense. The reusable modals are self-contained and do not need a service, but the parent component that renders a modal is expected to handle the modal's open/close state via
*ngIf