> For the complete documentation index, see [llms.txt](https://developers.oxylabs.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.oxylabs.io/products/cn/headless-browser/features/session-inspection.md).

# 会话检查

该 **会话检查** 工具是一个强大的 **调试功能** 是 Oxylabs 无头浏览器 的一项功能，利用 VNC (Virtual Network Computing) 技术为您的浏览器自动化会话提供实时可视访问。该工具在您的无头浏览器实例与可供您观察和 控制.

### 何时使用？

虽然 Oxylabs 无头浏览器 提供内置隐私能力、动态 CAPTCHA 处理和其他功能，但某些场景仍需要直接可视观察，以便：

* 诊断从日志或错误消息中无法明显看出的复杂问题
* 准确了解页面在浏览器中的呈现效果
* 验证自动化工作流是否正确执行
* 实时排查异常行为

### 使用示例

您可以通过添加 `o_vnc=true` 参数到连接端点，例如：

* **Chrome 浏览器：** `wss://username:password@ubc.oxylabs.io?o_vnc=true`
* **Firefox 浏览器：** `wss://username:password@ubs.oxylabs.io?o_vnc=true`

{% hint style="success" %}
此功能同时适用于 Playwright 和 Puppeteer 库。
{% endhint %}

{% tabs %}
{% tab title="Chrome（UBC）" %}

```javascript
const {chromium} = require('playwright');

(async () => {
    let page = null;
    let browser = null;

    try {
        // Use o_vnc=true parameter to connect
        browser = await chromium.connectOverCDP('wss://user:pass@ubc.oxylabs.io');
        const ctx = browser.contexts()[0];

        // Create a new page
        page = await ctx.newPage();
        page.on('console', async msg => {
            console.log(`BROWSER [${msg.type()}] ${msg.text()}`);
        });

        // Get the session ID using a CDP session
        let sesId = await (await ctx.newCDPSession(page)).send("__session_id");
        // Use UB novnc client or any WebSocket capable client to connect to vnc
        console.log(`Connect to VNC: https://vnc.headlesify.io/novnc/?id=${sesId.value}`);

        // Goto to a page
        await page.goto('https://duckduckgo.com');

        // Sleep for 10 minutes
        await new Promise(resolve => {
            setTimeout(resolve, 6000000);
        });
    }
    catch (e) {
        console.log("Finished with error:", e);
    } finally {
        if (page != null) await page.close();
        if (browser != null) await browser.close();
        process.exit(0);
    }
})();
```

{% endtab %}

{% tab title="Firefox（UBS）" %}

```javascript
const { firefox } = require('playwright');

(async () => {
    let page = null;
    let browser = null;

    try {
        // Use o_vnc=true parameter to connect
        browser = await firefox.connect('wss://user:pass@ubs.oxylabs.io?o_vnc=true');
        const ctx = await browser.newContext();

        // Create a new page
        page = await ctx.newPage()
        page.on('console', async msg => {
            console.log(`BROWSER [${msg.type()}] ${msg.text()}`);
        })

        // Get the session ID using a CDP session
        let sesId = await (await ctx.newCDPSession(page)).evaluate("__session_id")
        // Use UB novnc client or any WebSocket capable client to connect to VNC
        console.log(`Connect to VNC: https://vnc.headlesify.io/novnc/?id=${sesId.value}`);

        // Goto to a page
        await page.goto('https://duckduckgo.com');

        // Sleep for 10 minutes
        await new Promise(resolve => {
            setTimeout(resolve, 6000000);
        })
    }
    catch (e) {
        console.log("Finished with error:", e);
    } finally {
        if (page != null) await page.close();
        if (browser != null) await browser.close();
        process.exit(0);
    }
})();
```

{% endtab %}
{% endtabs %}


---

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