lbry-desktop/ui/js/actions/availability.js

import * as types from 'constants/action_types'
import lbry from 'lbry'
import {
  selectFetchingAvailability
} from 'selectors/availability'

export function doFetchAvailability(uri) {
  return function(dispatch, getState) {
    const state = getState()
    const alreadyFetching = !!selectFetchingAvailability(state)[uri]

    if (!alreadyFetching) {
      dispatch({
        type: types.FETCH_AVAILABILITY_STARTED,
        data: {uri}
      })

      lbry.get_availability({uri}).then((availability) => {
        dispatch({
          type: types.FETCH_AVAILABILITY_COMPLETED,
          data: {
            availability,
            uri,
          }
        })
      })
    }
  }
}