Vue 2 - vuex mapGetters and pass params

Question

Is it possible to pass params with mapGetters?

I have this in main Vue instance:

computed: {
    filterAuthors() {
        return this.$store.getters.filterAuthors(this.search.toLowerCase());
    }
}

this.search is bind to the input field via v-model="search=, and in my Vuex instance I have this getters:

getters: {
    filterAuthors: (state) => (search) => {
        return state.authors.filter((author) => {
            return author.name.toLowerCase().indexOf(search) >= 0;
        })
    }
},

This one is working fine, but I am trying to find a way (if it is possible) to use mapGetters and to pass the argument. Can this be done?

Answer 1

This can indeed be done! mapGetters simply maps this.yourGetterName to this.$store.getters.yourGetterName (see docs)

So to accomplish what you want:

import { mapGetters } from 'vuex'

export default {
  // ... the rest of your Vue instance/component
  computed: {
    // Mix your getter(s) into computed with the object spread operator
    ...mapGetters([
      'filteredAuthors'
      // ...
    ]),
    // Create another computed property to call your mapped getter while passing the argument
    filteredAuthorsBySearch () {
      return this.filteredAuthors(this.search.toLowerCase())
    }
  }
}

Answer 2

This is the closest you can do if you do want to pass the param into the store. However, a better to handle it would be making the param as a part of the store too and set the input field as a computed property with corresponding getter and setter to update the state. And then you can use mapGetter to get the results.

const { mapGetters } = Vuex

const authorsInput = [{ name: 'Stephen King'}, { name: 'Neal Stephenson'}, { name: 'Tina Fey'}, { name: 'Amy Poehler'}, { name: 'David Foster Wallace'}, { name: 'Dan Brown'}, { name: 'Mark Twain'}]

const store = new Vuex.Store({
  state: {
    srchInput: '',
    authors: authorsInput
  },
  getters: {
    filteredAuthors: (state) => state.authors
      .filter((author) => author
        .name
        .toLowerCase()
        .indexOf(state.srchInput.toLowerCase()) >= 0)
      .map((author) => author.name)
  },
  mutations: {
    UPDATE_SRCH_INPUT: (state, input) => state.srchInput = input
  },
})

new Vue({
  el: '#app',
  store,
   computed: Object.assign({
    srchInput: {
      get () { return store.state.srchInput},
      set (val) { store.commit('UPDATE_SRCH_INPUT', val) } 
    }
  }, mapGetters([
    'filteredAuthors'
  ]))
})

filterAuthors: (state) => (search) => {
        return state.authors.filter((author) => {
            return author.name.toLowerCase().indexOf(search) >= 0;
        })
    }

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.4.2/vue.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/vuex/2.3.1/vuex.js"></script>
<div id="app">
 <div>
    <input type="text" v-model="srchInput"/>
    <ul>
      <li v-for="author in filteredAuthors">{{author}}</li>
    </ul>
  </div>
</div>