actions.js

import * as mutations from '../../mutation-types'
import * as actions from '../../action-types'
import users from '../../../api/users'

export default {
  [ actions.SELECTED_USER ] (context, user) {
    context.commit(mutations.SELECTED_USER, user)
  },
  [ actions.FETCH_USERS ] (context) {
    return new Promise((resolve, reject) => {
      users.fetch().then(response => {
        context.commit(mutations.SET_USERS, response.data)
        resolve(response)
      }).catch(error => {
        reject(error)
      })
    })
  },
  [ actions.UPDATE_USER ] (context, user) {
    return new Promise((resolve, reject) => {
      users.update(user).then(response => {
        context.commit(mutations.USER, user)
        resolve(response)
      }).catch(error => {
        reject(error)
      })
    })
  }
}

getters.js

export default {
  selectedUser: state => state.selected_user,
  users: state => state.users
}

index.js

import getters from './getters'
import actions from './actions'
import mutations from './mutations'

const state = {
  selected_user: {},
  users: []
}

export default {
  state,
  getters,
  actions,
  mutations
}

mutations.js

import * as types from '../../mutation-types'

export default {
  [ types.SELECTED_USER ] (state, user) {
    state.selected_user = user
  },
  [ types.SET_USERS ] (state, users) {
    state.users = users
  }
}