understanding-sources

Use when working with sources, understanding event capture, or learning about the push interface. Covers browser, dataLayer, and server source patterns.

$ Installer

git clone https://github.com/elbwalker/walkerOS /tmp/walkerOS && cp -r /tmp/walkerOS/skills/understanding-sources ~/.claude/skills/walkerOS

// tip: Run this command in your terminal to install the skill

SKILL.md

View on GitHub →

name: understanding-sources description: Use when working with sources, understanding event capture, or learning about the push interface. Covers browser, dataLayer, and server source patterns.

Understanding walkerOS Sources

Overview

Sources capture events from the external world (browser DOM, dataLayer, HTTP requests, cloud functions) and feed them to the collector.

Core principle: Sources capture. They don't process or deliver—that's collector and destinations.

Source Interface

See packages/core/src/types/source.ts for canonical interface.

Method	Purpose
`push(input)`	Receive external input, emit events

Push Signatures by Type

Source Type	Signature	Example
Cloud Function	`push(req, res) → Promise<void>`	HTTP handler
Browser	`push(event, data) → Promise<void>`	DOM events
DataLayer	`push(event, data) → Promise<void>`	GTM-style

Key insight: Source push IS the handler. No wrappers needed.

// Direct deployment
http('handler', source.push);

Source Paths

Type	Path	Examples
Web	`packages/web/sources/`	browser, dataLayer
Server	`packages/server/sources/`	gcp

Browser Source

The browser source captures events from DOM using data attributes.

<button data-elb="product" data-elb-product="id:P123;name:Laptop">
  <span data-elbaction="click">Add to Cart</span>
</button>

See packages/web/sources/browser/ for implementation.

DataLayer Source

Captures events from a GTM-style dataLayer array.

window.dataLayer.push({
  event: 'product view',
  product: { id: 'P123', name: 'Laptop' },
});

See packages/web/sources/dataLayer/ for implementation.

Server Sources

Handle HTTP requests in cloud functions.

// GCP Cloud Function
export const handler = source.push;

See packages/server/sources/gcp/ for implementation.