Live API
A 'live' API, is an API where the data needs to be kept up to date.
This is accomplished by refreshing the API call in a specific interval.
API automated refresh
The following Vue mixin is configured by default through the core-server Vue plugin.
Shown below is a redacted version of that mixin to understand the inner workings.
  
Vue.mixin({
  created() {
    if(this.liveApi)
      this.$listenLive(this.api, this.api_data, this.liveApiInterval);
  },

  destroyed() {
    // ...
    clearInterval(this.$liveIntervalIds[key]);
    // ...
  },

  methods: {
    $listenLive(api, api_data, inerval) {
        // ...
        this.$liveIntervalIds.push(id);
        return id;
    }
  }
});

It allows us in a component to declare an api, data that should be passed and an interval.
An example of this would be:
  
<template>
  ...
</template>

<script>
  export default {
    data() {
      return {
        liveApi: true,                          // This will enable live refreshes
        api: 'statistics/live',                 // The api to be called
        api_data: { type: 'error_rate' },       // The data needed to be passed to the API calls
        liveApiInterval: 3500,                  // The interval in ms. for the automated API refreshes
        statistics: [],                         // A placeholder for the result of the API
      };
    },
  };
</script>

This component would call the
  statistics/live
api every 3.5 seconds, with
  { type: 'error_rate' }
as data.
Next steps
In the next chapter you will learn how the broadcast data in your cluster and to your users.