A LiveView based concurrent word processor supporting inserting/deleting/replacing/searching with an event log for tracking changes over the liveview process's lifespan. The Word Processor is implemented using an Agent for mananging state and is instantiated in the Application Supervision tree, rather than spawning an Agent for each Editor process. This allows multiple clients to access and write to the state at once, showing off the concurrnecy. I used schemaless changesets to validate the inputs on the frontend and PubSub to keep state insync across clients.
If I were to add something more to this I would abstract away the Agent behind a protocol (or behaviour but protocols are cooler), giving the consumer a public API and the ability to inject implementations at runtime. This can be used for changing to something like ETS/Ecto while maintaining the same interface.
The project has been set up with no database so start up is as simple as:
mix setup
iex -S mix phx.serverNow you can visit localhost:4000 from your browser.
As this application is stateful utilising a supervised process to persist state across actions will likely be best. Agents fit this purpose for the simplest option, ETS would also work well but operations are not atomic (iirc) so it would need a intermediary process managing state updates which complicates things and kills the benefits of ETS. SQLite could work with the right setup too.
As text needs to be concurrently editable, Agent should be supervised at the application level
Gonna use LiveView because LiveView is the bomb
Realised that I don't need the actual text field to be manually editable and that state maintained in the Agent, all statemanagement should happen through thhe actions laid out in the spec. Moving to a switchable mode form
I added PubSub to sync the state with events and a little ephemeral log. Also now using a schemaless changeset to handle the validations. Pretty happy with it.
I wasn't entirely sure which way to take searching so I just went with a true/false indicator.