Serverless Lighthouse

Using headless Chrome and Lambda, Serverless Lighthouse analyzes web apps and web pages, collecting modern performance metrics and insights on developer best practices.

Deployment

Install the required packages.

npm install --global serverless
npm install --save lighthouse
npm install --save serverless-plugin-chrome
npm install --save-dev serverless-attach-managed-policy

Once the packages are installed you must set your AWS credentials by defining AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environmental variables, or using an AWS profile. You can read more about this on the Serverless Credentials Guide.

In short, either:

export AWS_PROFILE=<your-profile-name>

or

export AWS_ACCESS_KEY_ID=<your-key-here>
export AWS_SECRET_ACCESS_KEY=<your-secret-key-here>

Then, to deploy the service and all of its functions:

serverless deploy -v

Use this to quickly upload and overwrite your AWS Lambda code on AWS, allowing you to develop faster.

serverless deploy function -f auditor

Usage

You can easily add a target to be audited and manipulate the performance data.

Setting up a test.

By adding in some serverless configs you can create a desktop or mobile audit target.

functions:
  auditor:
    handler: handler.audit
    events:
      - schedule:
          name: lighthouse-audit-trigger
          description: 'Audit the input target.'
          rate: rate(5 minutes)
          enabled: true
          input:
            target: https://www.example.com/
            mobile: false

This will create a desktop audit of "https://www.example.com/" and will run every 5 minutes.

Manipulate Performance Data

The output of the audit is a json blob that is anywhere from 30mb to 80mb in size. This can be saved off to a file and loaded in the Lighthouse Viewer at a later time.

You can use Lighthouse programmatically and manipulate the json blob

lighthouse(url, flags).then(function(results) {
  console.log('timestamp: ' + results.generatedTime)
  console.log('target: ' + results.url)
  console.log('total-time: ' + results.timing.total)
  console.log('score: ' + results.score)
})

Docs

• serverless
• lighthouse
• serverless-chrome