proposal for get and observe

[alisman]

What? Why?

Components need to be able to fetch data and then observe change to that same data. Rather than put the data in redux store, we allow components to subscribe to the QuerySession object.

Changes proposed in this pull request:

• a
• b

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[adamabeshouse]

Whereas this way, there has to be observer registration in any component that wants to use data, we could instead have only one object which observes, and keeps the data in the store fresh, and then use React and mapStateToProps to implement the observer pattern in components.

Why do you prefer the proposed approach?

[adufilie]

I pushed some changes, adding missing parts

[adufilie]

I've already solved this messy code issue in the past:
https://github.com/adufilie/WeaveJS/blob/namespaces/srcts/weavejs/util/ReactUtils.tsx#L339