How to set up analytics in Vue

Product analytics enable you to gather and analyze data about how users interact with your Vue.js app. To show you how to set up analytics, in this tutorial we create a basic Vue app, add PostHog, and use it to capture pageviews and custom events.

Creating a Vue app

To demonstrate the basics of PostHog analytics, we'll create a simple Vue 3 app with two pages and a link to navigate between them.

First, ensure Node.js is installed (version 18.0 or newer). Then install @vue/cli and create a new Vue app:

npm install -g @vue/cli
vue create vue-analytics

Make sure to select [Vue 3] babel, eslint as the Vue version.

Adding pages

Next, create two new files HomePage.vue and AboutPage.vue in src/components.

In HomePage.vue, add the following the code:

<template>
  <div>
    <h1>Home</h1>
    <router-link to="/about">Go to About</router-link>
  </div>
</template>

<script>
export default {
  name: 'HomePage'
}
</script>

In AboutPage.vue, add the following the code:

<template>
  <div>
    <h1>About</h1>
    <router-link to="/">Back Home</router-link>
  </div>
</template>

<script>
export default {
  name: 'AboutPage'
}
</script>

Next we set up the routing. First install Vue Router in your project:

npm install vue-router@4

In your src directory, create a new folder router and then a new file index.js:

cd ./src
mkdir router
cd router 
touch index.js

In router/index.js, import the components and define the routes:

import { createRouter, createWebHistory } from 'vue-router'
import HomePage from '../components/HomePage.vue'
import AboutPage from '../components/AboutPage.vue'

const routes = [
  {
    path: '/',
    name: 'HomePage',
    component: HomePage
  },
  {
    path: '/about',
    name: 'AboutPage',
    component: AboutPage
  }
]

const router = createRouter({
  history: createWebHistory(),
  routes
})

export default router

Then, update your App.vue to use the router-view. Replace the contents of this file with:

<template>
  <router-view></router-view>
</template>

<script>
export default {
  name: 'App'
}
</script>

Finally, set up main.js to use the router:

import { createApp } from 'vue'
import App from './App.vue'
import router from './router'

createApp(App).use(router).mount('#app')

The basic setup is now complete. Run npm run serve to see your app.

Adding PostHog

This tutorial shows how to integrate PostHog with Vue 3. If you're using Vue 2, see our Vue docs for how to integrate PostHog.

With our app set up, it’s time to install and set up PostHog. If you don't have a PostHog instance, you can sign up for free.

First install posthog-js.

npm install posthog-js

Create a new plugin by creating a new folder in your base directory called plugins and then a new file posthog.js:

mkdir plugins
cd plugins 
touch posthog.js

Add the following code to your posthog.js file:

import posthog from "posthog-js";

export default {
  install(app) {
    app.config.globalProperties.$posthog = posthog.init(
      "<ph_project_api_key>",
      {
        api_host: "<ph_client_api_host>",
      }
    );
  },
};

Replace <ph_project_api_key> and <ph_client_api_host> with your your PostHog API key and host. You can find these in your project settings.

Finally, activate your plugin in main.js:

import { createApp } from 'vue'
import App from './App.vue'
import router from './router'
import posthogPlugin from '../plugins/posthog';

createApp(App)
.use(posthogPlugin)
.use(router)
.mount('#app');

Once you’ve done this, reload your app and click the buttons a few times. You should see events appearing in the PostHog events explorer.

Capturing pageviews

You might notice that moving between pages only captures a single pageview event. This is because PostHog only captures pageview events when a page load is fired. Since Vue creates a single-page app, this only happens once, and the Vue router handles subsequent page changes.

If we want to capture every route change, we must write code to capture pageviews that integrates with the router.

In main.js, set up PostHog to capture pageviews in the router.afterEach function. Additionally, you can use nextTick so that the capture event fires only after the page is mounted.

import { createApp, nextTick } from 'vue'
import App from './App.vue'
import router from './router'
import posthogPlugin from '../plugins/posthog';

const app = createApp(App);
app.use(posthogPlugin)
.use(router)
.mount('#app');

router.afterEach((to, from, failure) => {
  if (!failure) {
    nextTick(() => {
      app.config.globalProperties.$posthog.capture('$pageview', { path: to.fullPath });
    });
  }
});

Now, every time a user moves between pages, PostHog captures a $pageview event, not just the first page load.

Lastly, go back to plugins/posthog.js and make sure to set capture_pageview in the PostHog initialization config to false. This turns off autocaptured pageviews and ensures you won’t double-capture pageviews on the first load.

import posthog from "posthog-js";

export default {
  install(app) {
    app.config.globalProperties.$posthog = posthog.init(
      "<ph_project_api_key>",
      {
        api_host: "<ph_client_api_host>",
        capture_pageview: false
      }
    );
  },
};

Capturing custom events

Beyond pageviews, there might be more events you want to capture. To do this, you can capture custom events with PostHog.

To showcase this, update the code in HomePage.vue with a button and captureCustomEvent method that uses PostHog to capture a home_button_clicked event:

<template>
  <div>
    <h1>Home</h1>
    <router-link to="/about">Go to About</router-link>
    <button @click="captureCustomEvent">Click Me</button>
  </div>
</template>

<script>
export default {
  name: 'HomePage',
  methods: {
    captureCustomEvent() {
      this.$posthog.capture('home_button_clicked', {
        'user_name': 'Max the Hedgehog' 
      });
    }
  }
}
</script>

Now when you click the button, PostHog captures the custom home_button_clicked event. Notice that we also added a property user_name to the event. This is helpful for filtering events in PostHog.

Further reading

• How to set up feature flags in Vue
• How to set up A/B tests in Vue
• How to set up surveys in Vue