/*
sitestat.js is meant to be included in the <head> like so:
<script src="path/to/sitestat.js" async></script>
See test-site/index.html for an example.
*/
/**
* The global websocket singleton. It's initialized at the bottom of this script.
* @type {WebSocket | null}
*/
let WS = null;
/**
* Sends some JSON object to sitestat.
* @param {object} data The data to send.
*/
function sendStat(data) {
if (WS.readyState === WebSocket.OPEN) {
WS.send(JSON.stringify(data));
} else {
console.warn("Couldn't send data because websocket is not open: ", data);
}
}
/**
* Handles any event encountered, and sends a small message to sitestat about it.
* @param {Event} event The event that occurred.
*/
function handleEvent(event) {
sendStat({
type: "event",
event: event.type
});
}
/**
* Gets the remote URL that sitestat is running at, from the query params of
* the script's `src` attribute. Throws an error if such a URL could not be
* found.
* @returns {string} The remote URL to connect to.
*/
function getRemoteUrl() {
const scriptUrl = document.currentScript.src;
const paramsIdx = scriptUrl.indexOf("?");
if (paramsIdx !== -1) {
const paramsStr = scriptUrl.substring(paramsIdx);
const params = new URLSearchParams(paramsStr);
const remoteUrl = params.get("remote-url");
if (remoteUrl !== null) {
return remoteUrl;
}
}
throw new Error("Missing `remote-url=...` query parameter on script src attribute.")
}
// The main script starts below:
if (window.navigator.webdriver) {
throw new Error("sitestat disabled for automated user agents.");
}
const remoteUrl = getRemoteUrl();
WS = new WebSocket(`ws://${remoteUrl}/ws`);
WS.onopen = () => {
// As soon as the connection is established, send some basic information
// about the current browsing session.
console.info(
"📈 Established a connection to %csitestat%c for %cnon-intrusive, non-identifiable%csite analytics. Learn more here: https://github.com/andrewlalis/sitestat",
"font-weight: bold; font-style: italic; font-size: large; color: #32a852; background-color: #2e2e2e; padding: 5px;",
"",
"font-style: italic;"
);
sendStat({
type: "ident",
href: window.location.href,
userAgent: window.navigator.userAgent,
viewport: {
width: window.innerWidth,
height: window.innerHeight
}
});
}
WS.onerror = console.error;
// Register various event listeners.
const events = ["click", "keyup", "keydown", "scroll", "copy"];
for (let i = 0; i < events.length; i++) {
document.addEventListener(events[i], handleEvent);
}