special-dispatch-app/app/services/api.js

const app = require('../app')
const _ = require('lodash')

app.run(function(api) {
  api.statistics = () => api.get('/api/statistics')

  let terminals = null
  api.terminals = () => terminals || (terminals = api.get('/api/terminals'))

  let terminalsDictionary = null
  api.terminalsDictionary = () => terminalsDictionary || (terminalsDictionary = api.terminals().then(terminals => 
    _.fromPairs(terminals.map(loc => [loc.key, loc]))
  ))
  api.terminal = (key) => api.terminals().then(async terminals =>
    (await api.terminalsDictionary())[key]
  )
  let staffMembers = null
  api.staffMembers = () => staffMembers || (staffMembers = api.get('/api/staff-members/all'))

  let staffMemberDictionary = null
  api.staffMemberDictionary = () => staffMemberDictionary || (staffMemberDictionary = api.staffMembers().then(staffMembers =>
    _.fromPairs(staffMembers.map(sm => [sm.id, sm]))
  ))

  let retailers = null
  api.retailers = () => retailers || (retailers = api.get('/api/retailers/all'))

  let retailerDictionary = null
  api.retailerDictionary = () => retailerDictionary || (retailerDictionary = api.retailers().then(retailers =>
    _.fromPairs(retailers.map(sm => [sm.id, sm]))
  ))

})