Consolidate state management

[turt2live]

Why?

In-memory state is held in a variety of stores following different patterns. This makes it hard to reason about the code, complicates changes and prevents multi-account support.

What?

We’ll devise a unified pattern for storing state and migrate all existing stores to the new system.

Plan

Tasks

Beta Give feedback

1. Convert remaining stores (probably need subtask for each one)
2. Remove SdkContextClass.instance

Internal references

myhours: https://app.myhours.com/#/projects/2028403/overview

[kegsay]

Immediate term:

• Review and land Store refactor: use non-global stores in components matrix-org/matrix-react-sdk#9293 which provides a way to pass around stores (state) in the app.

Short term:

• Convert other stores one by one to this new format, either by myself or by other willing contributors. Add Jest tests for each store when they get converted, mocking out other store dependencies and using untilEmission and untilDispatch to improve test reliability and reduce brittleness of earlier await styles and hard dependencies on other concrete store impls.

Medium term:

• When all stores are converted, remove SdkContextClass.instance - this would remove all stores from being accesible globally and pave the way for multi-account support. If you need stores, you'd either need to useContext if in a React component, or accept an instace of SdkContextClass in your constructor, which is the dependency injected at startup (e.g in MatrixChat).