ObservableStore

ObservableStore is a synchronous in-memory store for a single value, that you can subscribe to updates on.

const store = new ObservableStore(initState)
store.subscribe(function showValue(value) {
  console.log('saw value:', value)
})

store.putState(5) // "saw value: 5"
store.putState(true) // "saw value: true"
store.putState({ hello: 'world' }) // "saw value: { hello: 'world' }"

console.log(store.getState().hello) // "world"

streams

Each ObservableStore can be turned into an ObservableStoreStream. An ObservableStoreStream is a duplex stream that you can pipe new values into it or pipe its updated values out of it.

Special behavior: Doesnt buffer outgoing updates, writes latest state to dest on pipe.

const pipe = require('pump')
const asStream = require('obs-store/lib/asStream')

const storeOne = new ObservableStore(initState)
const storeTwo = new ObservableStore()

pipe(
  asStream(storeOne),
  transformStream,
  asStream(storeTwo)
)

Changelog

3.0.0

ObservableStore are no longer streams. You can create streams via asStream.