clarity-js/src/diagnostic/script.ts

An analytics library that uses web page interactions to generate aggregated insights

import { Event, Setting } from "@clarity-types/data";
import type { ScriptErrorData } from "@clarity-types/diagnostic";
import { FunctionNames } from "@clarity-types/performance";
import { bind } from "@src/core/event";
import encode from "./encode";

let history: { [key: string]: number } = {};
export let data: ScriptErrorData;

export function start(): void {
    bind(window, "error", handler);
    history = {};
}

function handler(error: ErrorEvent): boolean {
    handler.dn = FunctionNames.ScriptHandler;
    const e = error.error || error;
    // While rare, it's possible for code to fail repeatedly during the lifetime of the same page
    // In those cases, we only want to log the failure first few times and not spam logs with redundant information.
    if (!(e.message in history)) {
        history[e.message] = 0;
    }
    if (history[e.message]++ >= Setting.ScriptErrorLimit) {
        return true;
    }

    // Send back information only if the handled error has valid information
    if (e?.message) {
        data = {
            message: e.message,
            line: error.lineno,
            column: error.colno,
            stack: e.stack,
            source: error.filename,
        };

        encode(Event.ScriptError);
    }

    return true;
}