@nitedani/inspector-api/lib/esm/heap.js

A simple node module to access V8 inspector + some tools to export and read the data.

import * as utils from "./utils";
import { PassThrough } from "stream";
export default class Heap {
    session;
    constructor(session) {
        this.session = session;
    }
    async enable() {
        await utils.invokeFunction(this.session, "HeapProfiler.enable");
    }
    async disable() {
        await utils.invokeFunction(this.session, "HeapProfiler.disable");
    }
    async startSampling() {
        await utils.invokeFunction(this.session, "HeapProfiler.startSampling");
    }
    async stopSampling() {
        return utils.invokeStop("HeapProfiler.stopSampling", this.session);
    }
    async startTimeline() {
        await utils.invokeFunction(this.session, "HeapProfiler.startTrackingHeapObjects", { trackAllocations: true });
    }
    stopTimeline() {
        const stream = new PassThrough();
        const getChunk = (m) => {
            stream.push(m.params.chunk);
        };
        this.session.on("HeapProfiler.addHeapSnapshotChunk", getChunk);
        this.session.post("HeapProfiler.stopTrackingHeapObjects", (err) => {
            this.session.removeListener("HeapProfiler.addHeapSnapshotChunk", getChunk);
            stream.emit("finish");
            stream.emit("end");
            stream.end();
            if (err)
                throw err;
        });
        return stream;
    }
    takeSnapshot() {
        const stream = new PassThrough();
        const getChunk = (m) => {
            stream.push(m.params.chunk);
        };
        this.session.on("HeapProfiler.addHeapSnapshotChunk", getChunk);
        this.session.post("HeapProfiler.takeHeapSnapshot", (err, _r) => {
            this.session.removeListener("HeapProfiler.addHeapSnapshotChunk", getChunk);
            stream.emit("finish");
            stream.emit("end");
            stream.end();
            if (err)
                throw err;
        });
        return stream;
    }
}