Using Ophan Tracker JS

Browser JavaScript client for Ophan.

Install

$ npm install @guardian/ophan-tracker-js

Usage

Tracker JS contains multiple entry point files tailored to specific platforms. These include:

• ng.js (short for next-gen) for the theguardian.com
• manage-my-account.js for manage.theguardian.com
• support.js for support.theguardian.com
• membership.js for membership-related sections

Default Behaviour

The default entry point for the library is ng.js. With this entry point, the library automatically initializes itself on the global window object and provides a suite of functionalities to monitor user interactions, visibility, and more. The library will send an initial page view event on page load. You are then in control of sending other events to Ophan.

You can see example usage of the library on theguardian.com here

1. Import and start the library:

   The library should be imported and executed eagerly (non-lazily) to ensure proper initialization. The exact syntax may vary depending on your build tool or environment.

   import ophan from '@guardian/ophan-tracker-js';

2. Send Tracking Events with ophan.record():

   ophan.record({
       // Your tracking data in JSON format
   });

Usage with Typescript

Refer to the type definitions within the library for the structure of valid tracking events. The ophan.record() function accepts a type of EventPayload found here.

Example Usage

import ophan, { Product, ComponentEvent } from '@guardian/ophan-tracker-js';
import type { AbTest } from '@guardian/ophan-tracker-js';

const exampleProduct: TProduct = "APP_PREMIUM_TIER";
const exampleAbTest: AbTest = {
   name: "myAbTest",
   variant: "variant",
   campaignCodes: ["code1", "code2"]
};

const componentV2 = {
   componentType: "ACQUISITIONS_BUTTON",
   id: "component-id",
   products: new Set([exampleProduct]),
   campaignCode: "campaign-code",
   labels: new Set(["label1", "label2"]),
};

const componentEvent: ComponentEvent = {
   component: componentV2,
   action: "CLICK",
   value: "some-value",
   id: "event-id",
   abTest: exampleAbTest,
   targetingAbTest: exampleAbTest,
};

ophan.record({
   componentEvent: componentEvent
});

If you would like to add a new event type or event property which does not exist, please contact the Ophan team.

Sending events straight to the backend

Please consult with the Ophan team if you wish to do this.

The backend of tracker exposes two endpoints, img/1 which takes in page view events, and img/2 which takes in all other events. For events sent to the img/2 endpoint, a page view event MUST also be created via the img/1. Further down the Ophan and Datatech pipeline, events with the same page view ID are tied together for ease of querying and data analysis. Therefore, a page view event must be present.

Developing Ophan Tracker JS

The library is implemented using both Javascript and TypeScript, with the source code located in the src directory and its subdirectories. The project is set up to include both TypeScript (.ts) and JavaScript (.js) files, allowing for a mix of both languages in the library's implementation.

Typescript interfaces and types are developed in the types folder.

The TypeScript compiler is configured to generate compiled JavaScript files and corresponding declaration files (.d.ts) in the ./dist directory. The declaration files provide type information for the library's public API. The compiler also generates source map files for the declaration files.

Compile

    .../ophan/tracker-js $ npm run build-for-npm

Proxy tracker-js:

1. Install dependencies

   $ brew install lighttpd
   .../ophan/tracker-js $ npm install

2. In another terminal window:

   .../ophan/tracker-js $ lighttpd -f lighttpd.conf -D

3. Install FoxyProxy (https://getfoxyproxy.org/downloads/) in your browser and create a rule that forces j.ophan.co.uk to localhost 8000. (For me FoxyProxy needed a few switches on and off before it decided to start talking to lighttpd.)

4. In another terminal window, start a server that is running the Guardian frontend

5. Navigate to where you are running the Guardian locally (e.g. https://localhost:9000/uk)

6. Ensure FoxyProxy is enabled

7. Develop with pleasure

Publish

Two formats for release

When you make a change to Tracker JS, you must release on both these systems:

NPM

We use changesets for automated publishing of the NPM package:

1. Add a changeset, run the following command and follow the instructions

   .../ophan/tracker-js $ npx changeset

2. When you raise a PR, the changeset bot won’t correctly see that you have included a changeset – it only checks for the .changesets folder in the root of the repository, whereas we have it in a subdirectory. Don’t worry.

3. When the PR is merged, the changesets github action will create a new PR, example here. On merging this generated PR, the action will publish to NPM. (This checks the subdirectory correctly.)

S3 Bucket

• https://j.ophan.co.uk/ - CDN/S3, deployed through RiffRaff and used by some Guardian sites like https://jobs.theguardian.com/. An advantage of this approach is that sites using it immediately get Tracker JS updates, without developer intervention.

Rollup

The generated files from Rollup (using the build-for-cdn script in package.json) are only used for publishing to the CDN to use SystemJS / AMD