ScalaJS undo/redo

This repository is to experiment with undo/redo approaches in ScalaJS, in particular using Diode. Diode is used as an app state container. To mutate this state, we send actions to thios state container.

We have several ways of implementing the undo/redo behaviour :

• Save the whole app state at each new action in a queue and look in the queue when we want to undo an action.
• Use "undoable" diode actions, that implement 2 functions :
  • the update function that updates the current state and gets the next state
  • the undo function that is the update opposite behaviour. Then we keep a list of past actions, and when we want to undo an action, we pick the first action in the pas actions queue and run the undo method.

To run locally

sbt run

Visit http://localhost:8080

Using the server

python3 -m venv venv
. venv/bin/activate
pip install -r requirements.txt
FLASK_ENV=development python server.py

$ curl http://localhost:5000/recipes

$ curl -X POST -H 'Content-Type: application/json' http://localhost:5000/recipes -d '{"id":"tiramisu","name":"tiramisu","ingredients":["coffee","eggs","mascarpone","savoiardi"],"instructions":["instruction 1","instruction 2"]}'

$ curl -X DELETE http://localhost:5000/recipes/pancakes

Action Items

• Add form for adding a recipe.
• Allow updating one recipe.
• Limit actions history to 5 items.
• On the backend, merge the POST and DELETE endpoints.
• Disable/enable undo redo buttons when the corresponding list is empty
• Add akka-http server
• Move the python server to akka-http
• Add logic in the backend
• Add elasticsearch and elastic4s