go-rod-master

name	go-rod-master
description	Comprehensive guide for browser automation and web scraping with go-rod (Chrome DevTools Protocol) including stealth anti-bot-detection patterns.
risk	safe
source	https://github.com/go-rod/rod

Go-Rod Browser Automation Master

Overview

Rod is a high-level Go driver built directly on the Chrome DevTools Protocol for browser automation and web scraping. Unlike wrappers around other tools, Rod communicates with the browser natively via CDP, providing thread-safe operations, chained context design for timeouts/cancellation, auto-wait for elements, correct iframe/shadow DOM handling, and zero zombie browser processes.

The companion library go-rod/stealth injects anti-bot-detection evasions based on puppeteer-extra stealth, hiding headless browser fingerprints from detection systems.

When to Use This Skill

• Use when the user asks to scrape, automate, or test a website using Go.
• Use when the user needs a headless browser for dynamic/SPA content (React, Vue, Angular).
• Use when the user mentions stealth, anti-bot, avoiding detection, Cloudflare, or bot detection bypass.
• Use when the user wants to work with the Chrome DevTools Protocol (CDP) directly from Go.
• Use when the user needs to intercept or hijack network requests in a browser context.
• Use when the user asks about concurrent browser scraping or page pooling in Go.
• Use when the user is migrating from chromedp or Playwright Go and wants a simpler API.

Safety & Risk

Risk Level: 🔵 Safe

• Read-Only by Default: Default behavior is navigating and reading page content (scraping/testing).
• Isolated Contexts: Browser contexts are sandboxed; cookies and storage do not persist unless explicitly saved.
• Resource Cleanup: Designed around Go's defer pattern — browsers and pages close automatically.
• No External Mutations: Does not modify external state unless the script explicitly submits forms or POSTs data.

Installation

# Core rod library
go get github.com/go-rod/rod@latest

# Stealth anti-detection plugin (ALWAYS include for production scraping)
go get github.com/go-rod/stealth@latest

Rod auto-downloads a compatible Chromium binary on first run. To pre-download:

go run github.com/nichochar/go-rod.github.io/cmd/launcher@latest

Core Concepts

Browser Lifecycle

Rod manages three layers: Browser → Page → Element.

// Launch and connect to a browser
browser := rod.New().MustConnect()
defer browser.MustClose()

// Create a page (tab)
page := browser.MustPage("https://example.com")

// Find an element
el := page.MustElement("h1")
fmt.Println(el.MustText())

Must vs Error Patterns

Rod provides two API styles for every operation:

Style	Method	Use Case
Must	MustElement(), MustClick(), MustText()	Scripting, debugging, prototyping. Panics on error.
Error	Element(), Click(), Text()	Production code. Returns error for explicit handling.

Production pattern:

el, err := page.Element("#login-btn")
if err != nil {
    return fmt.Errorf("login button not found: %w", err)
}
if err := el.Click(proto.InputMouseButtonLeft, 1); err != nil {
    return fmt.Errorf("click failed: %w", err)
}

Scripting pattern with Try:

err := rod.Try(func() {
    page.MustElement("#login-btn").MustClick()
})
if errors.Is(err, context.DeadlineExceeded) {
    log.Println("timeout finding login button")
}

Context & Timeout

Rod uses Go's context.Context for cancellation and timeouts. Context propagates recursively to all child operations.

// Set a 5-second timeout for the entire operation chain
page.Timeout(5 * time.Second).
    MustWaitLoad().
    MustElement("title").
    CancelTimeout(). // subsequent calls are not bound by the 5s timeout
    Timeout(30 * time.Second).
    MustText()

Element Selectors

Rod supports multiple selector strategies:

// CSS selector (most common)
page.MustElement("div.content > p.intro")

// CSS selector with text regex matching
page.MustElementR("button", "Submit|Send")

// XPath
page.MustElementX("//div[@class='content']//p")

// Search across iframes and shadow DOM (like DevTools Ctrl+F)
page.MustSearch(".deeply-nested-element")

Auto-Wait

Rod automatically retries element queries until the element appears or the context times out. You do not need manual sleeps:

// This will automatically wait until the element exists
el := page.MustElement("#dynamic-content")

// Wait until the element is stable (position/size not changing)
el.MustWaitStable().MustClick()

// Wait until page has no pending network requests
wait := page.MustWaitRequestIdle()
page.MustElement("#search").MustInput("query")
wait()

---

Stealth & Anti-Bot Detection (go-rod/stealth)

IMPORTANT: For any production scraping or automation against real websites, ALWAYS use stealth.MustPage() instead of browser.MustPage(). This is the single most important step for avoiding bot detection.

How Stealth Works

The go-rod/stealth package injects JavaScript evasions into every new page that:

• Remove navigator.webdriver — the primary headless detection signal.
• Spoof WebGL vendor/renderer — presents real GPU info (e.g., "Intel Inc." / "Intel Iris OpenGL Engine") instead of headless markers like "Google SwiftShader".
• Fix Chrome plugin array — reports proper PluginArray type with realistic plugin count.
• Patch permissions API — returns "prompt" instead of bot-revealing values.
• Set realistic languages — reports en-US,en instead of empty arrays.
• Fix broken image dimensions — headless browsers report 0x0; stealth fixes this to 16x16.

Usage

Creating a stealth page (recommended for all production use):

import (
    "github.com/go-rod/rod"
    "github.com/go-rod/stealth"
)

browser := rod.New().MustConnect()
defer browser.MustClose()

// Use stealth.MustPage instead of browser.MustPage
page := stealth.MustPage(browser)
page.MustNavigate("https://bot.sannysoft.com")

With error handling:

page, err := stealth.Page(browser)
if err != nil {
    return fmt.Errorf("failed to create stealth page: %w", err)
}
page.MustNavigate("https://example.com")

Using stealth.JS directly (advanced — for custom page creation):

// If you need to create the page yourself (e.g., with specific options),
// inject stealth.JS manually via EvalOnNewDocument
page := browser.MustPage()
page.MustEvalOnNewDocument(stealth.JS)
page.MustNavigate("https://example.com")

Verifying Stealth

Navigate to a bot detection test page to verify evasions:

page := stealth.MustPage(browser)
page.MustNavigate("https://bot.sannysoft.com")
page.MustScreenshot("stealth_test.png")

Expected results for a properly stealth-configured browser:

• WebDriver: missing (passed)
• Chrome: present (passed)
• Plugins Length: 3 (not 0)
• Languages: en-US,en

---

Implementation Guidelines

1. Launcher Configuration

Use the launcher package to customize browser launch flags:

import "github.com/go-rod/rod/lib/launcher"

url := launcher.New().
    Headless(true).             // false for debugging
    Proxy("127.0.0.1:8080").    // upstream proxy
    Set("disable-gpu", "").     // custom Chrome flag
    Delete("use-mock-keychain"). // remove a default flag
    MustLaunch()

browser := rod.New().ControlURL(url).MustConnect()
defer browser.MustClose()

Debugging mode (visible browser + slow motion):

l := launcher.New().
    Headless(false).
    Devtools(true)
defer l.Cleanup()

browser := rod.New().
    ControlURL(l.MustLaunch()).
    Trace(true).
    SlowMotion(2 * time.Second).
    MustConnect()

2. Proxy Support

// Set proxy at launch
url := launcher.New().
    Proxy("socks5://127.0.0.1:1080").
    MustLaunch()

browser := rod.New().ControlURL(url).MustConnect()

// Handle proxy authentication
go browser.MustHandleAuth("username", "password")()

// Ignore SSL certificate errors (for MITM proxies)
browser.MustIgnoreCertErrors(true)

3. Input Simulation

import "github.com/go-rod/rod/lib/input"

// Type into an input field (replaces existing value)
page.MustElement("#email").MustInput("[e-mail]")

// Simulate keyboard keys
page.Keyboard.MustType(input.Enter)

// Press key combinations
page.Keyboard.MustPress(input.ControlLeft)
page.Keyboard.MustType(input.KeyA)
page.Keyboard.MustRelease(input.ControlLeft)

// Mouse click at coordinates
page.Mouse.MustClick(input.MouseLeft)
page.Mouse.MustMoveTo(100, 200)

4. Network Request Interception (Hijacking)

router := browser.HijackRequests()
defer router.MustStop()

// Block all image requests
router.MustAdd("*.png", func(ctx *rod.Hijack) {
    ctx.Response.Fail(proto.NetworkErrorReasonBlockedByClient)
})

// Modify request headers
router.MustAdd("*api.example.com*", func(ctx *rod.Hijack) {
    ctx.Request.Req().Header.Set("Authorization", "Bearer token123")
    ctx.MustLoadResponse()
})

// Modify response body
router.MustAdd("*.js", func(ctx *rod.Hijack) {
    ctx.MustLoadResponse()
    ctx.Response.SetBody(ctx.Response.Body() + "\n// injected")
})

go router.Run()

5. Waiting Strategies

// Wait for page load event
page.MustWaitLoad()

// Wait for no pending network requests (AJAX idle)
wait := page.MustWaitRequestIdle()
page.MustElement("#search").MustInput("query")
wait()

// Wait for element to be stable (not animating)
page.MustElement(".modal").MustWaitStable().MustClick()

// Wait for element to become invisible
page.MustElement(".loading").MustWaitInvisible()

// Wait for JavaScript condition
page.MustWait(`() => document.title === 'Ready'`)

// Wait for specific navigation/event
wait := page.WaitEvent(&proto.PageLoadEventFired{})
page.MustNavigate("https://example.com")
wait()

6. Race Selectors (Multiple Outcomes)

Handle pages where the result can be one of several outcomes (e.g., login success vs error):

page.MustElement("#username").MustInput("user")
page.MustElement("#password").MustInput("pass").MustType(input.Enter)

// Race between success and error selectors
elm := page.Race().
    Element(".dashboard").MustHandle(func(e *rod.Element) {
        fmt.Println("Login successful:", e.MustText())
    }).
    Element(".error-message").MustDo()

if elm.MustMatches(".error-message") {
    log.Fatal("Login failed:", elm.MustText())
}

7. Screenshots & PDF

// Full-page screenshot
page.MustScreenshot("page.png")

// Custom screenshot (JPEG, specific region)
img, _ := page.Screenshot(true, &proto.PageCaptureScreenshot{
    Format:  proto.PageCaptureScreenshotFormatJpeg,
    Quality: gson.Int(90),
    Clip: &proto.PageViewport{
        X: 0, Y: 0, Width: 1280, Height: 800, Scale: 1,
    },
})
utils.OutputFile("screenshot.jpg", img)

// Scroll screenshot (captures full scrollable page)
img, _ := page.MustWaitStable().ScrollScreenshot(nil)
utils.OutputFile("full_page.jpg", img)

// PDF export
page.MustPDF("output.pdf")

8. Concurrent Page Pool

pool := rod.NewPagePool(5) // max 5 concurrent pages

create := func() *rod.Page {
    return browser.MustIncognito().MustPage()
}

var wg sync.WaitGroup
for _, url := range urls {
    wg.Add(1)
    go func(u string) {
        defer wg.Done()

        page := pool.MustGet(create)
        defer pool.Put(page)

        page.MustNavigate(u).MustWaitLoad()
        fmt.Println(page.MustInfo().Title)
    }(url)
}
wg.Wait()

pool.Cleanup(func(p *rod.Page) { p.MustClose() })

9. Event Handling

// Listen for console.log output
go page.EachEvent(func(e *proto.RuntimeConsoleAPICalled) {
    if e.Type == proto.RuntimeConsoleAPICalledTypeLog {
        fmt.Println(page.MustObjectsToJSON(e.Args))
    }
})()

// Wait for a specific event before proceeding
wait := page.WaitEvent(&proto.PageLoadEventFired{})
page.MustNavigate("https://example.com")
wait()

10. File Download

wait := browser.MustWaitDownload()

page.MustElementR("a", "Download PDF").MustClick()

data := wait()
utils.OutputFile("downloaded.pdf", data)

11. JavaScript Evaluation

// Execute JS on the page
page.MustEval(`() => console.log("hello")`)

// Pass parameters and get return value
result := page.MustEval(`(a, b) => a + b`, 1, 2)
fmt.Println(result.Int()) // 3

// Eval on a specific element ("this" = the DOM element)
title := page.MustElement("title").MustEval(`() => this.innerText`).String()

// Direct CDP calls for features Rod doesn't wrap
proto.PageSetAdBlockingEnabled{Enabled: true}.Call(page)

12. Loading Chrome Extensions

extPath, _ := filepath.Abs("./my-extension")

u := launcher.New().
    Set("load-extension", extPath).
    Headless(false). // extensions require headed mode
    MustLaunch()

browser := rod.New().ControlURL(u).MustConnect()

---

Examples

See the examples/ directory for complete, runnable Go files:

• examples/basic_scrape.go — Minimal scraping example
• examples/stealth_page.go — Anti-detection with go-rod/stealth
• examples/request_hijacking.go — Intercepting and modifying network requests
• examples/concurrent_pages.go — Page pool for concurrent scraping

---

Best Practices

• ✅ ALWAYS use stealth.MustPage(browser) instead of browser.MustPage() for real-world sites.
• ✅ ALWAYS defer browser.MustClose() immediately after connecting.
• ✅ Use the error-returning API (not Must*) in production code.
• ✅ Set explicit timeouts with .Timeout() — never rely on defaults for production.
• ✅ Use browser.MustIncognito().MustPage() for isolated sessions.
• ✅ Use PagePool for concurrent scraping instead of spawning unlimited pages.
• ✅ Use MustWaitStable() before clicking elements that might be animating.
• ✅ Use MustWaitRequestIdle() after actions that trigger AJAX calls.
• ✅ Use launcher.New().Headless(false).Devtools(true) for debugging.
• ❌ NEVER use time.Sleep() for waiting — use Rod's built-in wait methods.
• ❌ NEVER create a new Browser per task — create one Browser, use multiple Page instances.
• ❌ NEVER use browser.MustPage() for production scraping — use stealth.MustPage().
• ❌ NEVER ignore errors in production — always handle them explicitly.
• ❌ NEVER forget to defer-close browsers, pages, and hijack routers.

Common Pitfalls

• Problem: Element not found even though it exists on the page. Solution: The element may be inside an iframe or shadow DOM. Use page.MustSearch() instead of page.MustElement() — it searches across all iframes and shadow DOMs.

• Problem: Click doesn't work because the element is animating. Solution: Call el.MustWaitStable() before el.MustClick().

• Problem: Bot detection despite using stealth. Solution: Combine stealth.MustPage() with: randomized viewport sizes, realistic User-Agent strings, human-like input delays between keystrokes, and random idle behaviors (scroll, hover).

• Problem: Browser process leaks (zombie processes). Solution: Always defer browser.MustClose(). Rod uses leakless to kill zombies after main process crash, but explicit cleanup is preferred.

• Problem: Timeout errors on slow pages. Solution: Use chained context: page.Timeout(30 * time.Second).MustWaitLoad(). For AJAX-heavy pages, use MustWaitRequestIdle() instead of MustWaitLoad().

• Problem: HijackRequests router not intercepting requests. Solution: You must call go router.Run() after setting up routes, and defer router.MustStop() for cleanup.

Limitations

• CAPTCHAs: Rod does not include CAPTCHA solving. External services (2captcha, etc.) must be integrated separately.
• Extreme Anti-Bot: While go-rod/stealth handles common detection (WebDriver, plugin fingerprints, WebGL), extremely strict systems (some Cloudflare configurations, Akamai Bot Manager) may still detect automation. Additional measures (residential proxies, human-like behavioral patterns) may be needed.
• DRM Content: Cannot interact with DRM-protected media (e.g., Widevine).
• Resource Usage: Each browser instance consumes significant RAM (~100-300MB+). Use PagePool and limit concurrency on memory-constrained systems.
• Extensions in Headless: Chrome extensions do not work in headless mode. Use Headless(false) with XVFB for server environments.
• Platform: Requires a Chromium-compatible browser. Does not support Firefox or Safari.

Documentation References

• Official Documentation — Guides, tutorials, FAQ
• Go API Reference — Complete type and method documentation
• go-rod/stealth — Anti-bot detection plugin
• Examples (source) — Official example tests
• Rod vs Chromedp Comparison — Migration reference
• Chrome DevTools Protocol Docs — Underlying protocol reference
• Chrome CLI Flags Reference — Launcher flag documentation
• references/api-reference.md — Quick-reference cheat sheet