vuex-cache

Cache dispatched actions and prevent repeated requests and heavy actions.

Compatibility

• Map and Promise are required (you can use polyfills, like @babel/polyfill);
• Any Vue version, since vuex-cache just deals with Vuex;
• Vuex versions 1, 2 and 3.

Installation

vuex-cache is published in the NPM registry and can be installed using any compatible package manager.

npm install vuex-cache --save

# For Yarn use the command below.
yarn add vuex-cache

Import createCache factory and use on Vuex's plugins.

import Vue from 'vue';
import Vuex, { Store } from 'vuex';
import createCache from 'vuex-cache';

const store = new Store({
  plugins: [createCache()],
  ...
});

Installation on Nuxt.js

Global plugin (~/plugins/vuex-cache.js)

Only use it if you're not using Classic Mode.

Create a module on plugins to setup vuex-cache. Call vuex-cache with your options, then call returned value with store on onNuxtReady event.

~/plugins/vuex-cache.js

import createVuexCache from 'vuex-cache';

export default ({ store }) => {
  const options = {
    timeout: 2 * 60 * 60 * 1000 // Equal to 2 hours in milliseconds.
  };

  const setupVuexCache = createVuexCache(options);

  window.onNuxtReady(() => setupVuexCache(store));
};

Then just add this plugin to your nuxt configuration. Like the example below.

~/nuxt.config.js

module.exports = {
  ...,
  plugins: [
    ...,
    { src: '~/plugins/vuex-cache.js', ssr: false },
  ]
};

Global store (~/store/index.js)

import createCache from 'vuex-cache';

export const plugins = [
    createCache()
]

Usage

After install you can use cache property to call cache methods.

const store = new Store({
  ...,
  actions: {
    'FETCH_USER': async (_, id) => {
      const response = await fetch(baseURL + '/user/' + id);
      const { users } = await response.json();
      return users;
    }
  }
});

store.cache.dispatch('FETCH_USER', 1);
//=> Promise { User }

API

createCache

The default exported factory to create Vuex's store plugin. It define cache property on Store instances.

import { Store } from 'vuex';
import createCache from 'vuex-cache';

const store = new Store({
  plugins: [
    createCache()
  ]
})

cacheAction

A named exported function to enhance actions and define cache property on ActionContext instances.

import { cacheAction } from 'vuex-cache';

// ...

const actions = {
  'FETCH_STARGAZERS': cacheAction(
    ({ cache, commit }, payload) => (
      cache.dispatch('FETCH_REPOSITORIES')
        .then((repos) => Promise.all(repos.map(getStargazers)))
        .then((stargazers) => {
          commit('STARGAZERS', [].concat(...stargazers));
        })
    )
  ),

  'SET_STARGAZERS': (context, payload) => { ... }
}

store.cache.dispatch

Dispatches an action if it's not cached and set it on cache, otherwise it returns cached Promise.

It uses action name and payload as cache key.

store.cache.dispatch('user/GET_USER');
//=> Promise { User }

// Returns value without dispatching the action again.
store.cache.dispatch('user/GET_USER');
//=> Promise { User }

store.cache.has

Check if an action is cached. Returns true if action is cached and false otherwise.

store.cache.has('user/GET_USER');
//=> true

store.cache.has('FETCH_REPOSITORY', 219);
//=> false

store.cache.delete

Delete an action from cache. Returns true if action is deleted and false otherwise.

store.cache.delete('user/GET_USER');
//=> true

store.cache.delete('FETCH_REPOSITORY', 219);
//=> false

Only exact matches are deleted. Use store.cache.clear to delete all items or by action name.

store.cache.clear

Clear the cache, delete all actions from it. Returns true if cache is cleared and false otherwise.

store.cache.clear();
//=> true

If using the type parameter, only actions with the specified type are deleted from cache and the number of deleted keys is returned.

// store.cache.dispatch('FETCH_REPOSITORIES', { page: 1 });
// store.cache.dispatch('FETCH_REPOSITORIES', { page: 2 });
store.cache.clear('FETCH_REPOSITORIES');
//=> 2

store.cache.state

Warning! Don't use this method in production.

Helper method for debugging. Prints the current value of the cache (state).

store.cache.dispatch('FETCH_REPOSITORIES', { page: 1 });
store.cache.dispatch('FETCH_REPOSITORIES', { page: 2 });
store.cache.state();
//=> Map(2){...}

mapCacheActions

Create component methods that dispatch a cached action.

import { mapCacheActions } from 'vuex-cache';

export default {
  name: 'Users',
  methods: {
    ...mapCacheActions(['FETCH_REPOSITORY']),
    ...mapCacheActions('user', ['GET_USER']),
  },
  async mounted() {
    this.GET_USER();
    this.FETCH_REPOSITORY(219, {
      timeout: 30000
    });
  }
}

Payload

The payload value is undefined as default and supports functions, primitive values and JSON parseable objects.

store.cache.dispatch, store.cache.has and store.cache.delete supports payload object as argument.

store.cache.dispatch({
  type: 'FETCH_REPOSITORY',
  payload: 198
});
//=> Promise { Repository }

store.cache.has({
  type: 'FETCH_REPOSITORY',
  payload: 198
});
//=> true

store.cache.delete({
  type: 'FETCH_REPOSITORY',
  payload: 198
});
//=> true

Timeout

timeout option is 0 as default and define cache duration is milliseconds.

0 means it has no defined duration, no timeout.

const store = new Store({
  plugins: [
    createCache({ timeout: 10000 })
  ],
  ...
});

After milliseconds defined in timeout option an action is expired from cache.

// This dispatches the action and set it on cache.
store.cache.dispatch('FETCH_REPOSITORY', 219);
//=> Promise { Repository }

store.cache.has('FETCH_REPOSITORY', 219);
//=> true

setTimeout(() => {

  // It returns false because the action is expired.
  store.cache.has('FETCH_REPOSITORY', 219);
  //=> false

  // This dispatches the action again because the action is expired.
  store.cache.dispatch('FETCH_REPOSITORY', 219);
  //=> Promise { Repository }
}, 10000)

Store's timeout can be overwritten by dispatch timeout option in Dispatch Options or in payload.

store.cache.dispatch('FETCH_REPOSITORY', 219, {
  timeout: 30000
});

// OR

store.cache.dispatch({
  type: 'FETCH_REPOSITORY',
  payload: 219,
  timeout: 30000
});