@govaris/plugin-varis-lighthouse-plugin v0.3.0

@backstage/plugin-lighthouse

A frontend for lighthouse-audit-service, this plugin allows you to trigger Lighthouse audits on websites and track them over time.

Introduction

Google's Lighthouse auditing tool for websites is a great open-source resource for benchmarking and improving the accessibility, performance, SEO, and best practices of your site. At Spotify, we keep track of Lighthouse audit scores over time to look at trends and overall areas for investment.

This plugin allows you to generate on-demand Lighthouse audits for websites, and to track the trends for the top-level categories of Lighthouse at a glance.

You can learn more in our blog post Introducing Lighthouse for Backstage.

List of audits	Specific audit

In the future, we hope to add support for scheduling audits (which we do internally), as well as allowing custom runs of Lighthouse to be ingested (for auditing sites that require authentication or some session state).

Getting Started

To get started, you will need a running instance of lighthouse-audit-service. It's likely you will need to enable CORS to integrate with Backstage, so initialize the lighthouse-audit-service with the environment variable LAS_CORS set to true.

When you have an instance running that Backstage can hook into, first install the plugin into your app:

# From your Backstage root directory
cd packages/app
yarn add @backstage/plugin-lighthouse

Modify your app routes in App.tsx to include the LighthousePage component exported from the plugin, for example:

// In packages/app/src/App.tsx
import { LighthousePage } from '@backstage/plugin-lighthouse';

const routes = (
  <FlatRoutes>
    {/* ...other routes */}
    <Route path="/lighthouse" element={<LighthousePage />} />

Then configure the lighthouse-audit-service URL in your app-config.yaml.

lighthouse:
  baseUrl: http://your-service-url

Integration with the Catalog

The Lighthouse plugin can be integrated into the catalog so that Lighthouse audit information relating to a component can be displayed within that component's entity page. In order to link an Entity to its Lighthouse audits, the entity must be annotated as follows:

apiVersion: backstage.io/v1alpha1
kind: Component
metadata:
  # ...
  annotations:
    lighthouse.com/website-url: # A single website url e.g. https://backstage.io/

NOTE: The plugin only supports one website URL per component at this time.

Add a Lighthouse tab to the entity page:

// In packages/app/src/components/catalog/EntityPage.tsx
import { EntityLighthouseContent } from '@backstage/plugin-lighthouse';

const websiteEntityPage = (
  <EntityLayout>
    {/* other tabs... */}
    <EntityLayout.Route path="/lighthouse" title="Lighthouse">
      <EntityLighthouseContent />
    </EntityLayout.Route>

NOTE: The embedded router renders page content without a header section allowing it to be rendered within a catalog plugin page.

Add a Lighthouse card to the overview tab on the EntityPage:

// In packages/app/src/components/catalog/EntityPage.tsx
import {
  EntityLastLighthouseAuditCard,
  isLighthouseAvailable,
} from '@backstage/plugin-lighthouse';

const overviewContent = (
  <Grid container spacing={3} alignItems="stretch">
    {/* ...other content */}
    <EntitySwitch>
      <EntitySwitch.Case if={isLighthouseAvailable}>
        <Grid item md={6}>
          <EntityLastLighthouseAuditCard />
        </Grid>
      </EntitySwitch.Case>
    </EntitySwitch>