sjht-web-screenshot

Capture screenshots of web pages running on local or remote servers using Puppeteer in headless Chromium. Use when user asks to screenshot web pages, capture web UI, take website screenshots, or document web application interfaces. Supports login-required SPAs (Vue/React/Angular) by performing form-based authentication before navigating. Generates screenshots and an optional result.json with per-page descriptions.

Web Screenshot

Capture screenshots of web pages (especially SPA applications) with automatic login handling.

Dependencies

• puppeteer-core (npm global)
• chromium-browser (/usr/bin/chromium-browser)
• Node.js

Verify with: which chromium-browser && npm ls -g puppeteer-core

Quick Start

node <skill_dir>/scripts/screenshot.js <config.json>

Config Format

{
  "baseUrl": "http://192.168.7.66:8080",
  "outputDir": "/root/screenpics/my-capture",
  "resolution": [1920, 1080],
  "login": {
    "url": "/login",
    "usernameSelector": "input[placeholder='请输入用户名']",
    "passwordSelector": "input[type='password']",
    "submitSelector": "button.el-button--primary",
    "credentials": { "username": "admin", "password": "123456" }
  },
  "pages": [
    { "name": "01_dashboard", "path": "/dashboard", "waitMs": 3000 },
    { "name": "02_project_list", "path": "/project/list", "waitMs": 2000 }
  ],
  "descriptions": {
    "01_dashboard": "工作台首页，展示KPI卡片和图表。",
    "02_project_list": "项目管理列表页面。"
  }
}

Login Flow (SPA Authentication)

The script handles Vue/React SPA login by:

1. Navigating to the login page
2. Setting input values via native HTMLInputElement.value setter + dispatching input events (Vue-reactive compatible)
3. Clicking the submit button
4. Waiting for SPA router navigation (URL change)
5. Using Vue's $router.push() for subsequent page navigation (avoids Pinia/Redux store reset on full page reload)

Fields

Field	Required	Description
baseUrl	✅	Base URL of the web app
outputDir	✅	Output directory for screenshots
resolution	No	Viewport size [width, height], default [1920, 1080]
login	No	Login config (skip for public pages)
login.usernameSelector	✅*	CSS selector for username input
login.passwordSelector	✅*	CSS selector for password input
login.submitSelector	✅*	CSS selector for submit button
login.credentials	✅*	{ username, password }
pages	✅	Array of pages to capture
pages[].name	✅	Filename prefix (e.g. 01_dashboard)
pages[].path	✅	URL path (e.g. /dashboard)
pages[].waitMs	No	Extra wait in ms after navigation (default 2000)
descriptions	No	Map of name → description text (included in result.json)

Output

• {outputDir}/{name}.png — one PNG per page
• {outputDir}/result.json — metadata with filenames, titles, URLs, descriptions

result.json Format

{
  "project": "auto-generated",
  "captureDate": "2026-03-22",
  "baseUrl": "...",
  "resolution": "1920x1080",
  "screenshots": [
    {
      "filename": "01_dashboard.png",
      "title": "Dashboard",
      "url": "...",
      "description": "..."
    }
  ]
}

Capture Login Page Too

To include the login page as the first screenshot, add it to pages with a special flag:

{
  "pages": [
    { "name": "00_login", "path": "/login", "isLoginPage": true, "waitMs": 2000 }
  ]
}

When isLoginPage: true, the script captures this page before performing login.

Advanced: Custom Vue Store Login

If the form-based login doesn't work (e.g., custom auth flow), use storeLogin instead:

{
  "login": {
    "url": "/login",
    "storeLogin": {
      "storeName": "user",
      "method": "login",
      "args": ["平台管理员"]
    }
  }
}

This directly calls pinia._s.get(storeName).method(...args) via CDP.

Troubleshooting

• Blank charts (ECharts/Chart.js): Headless Chromium has no GPU. Charts using Canvas may render empty. Use --disable-gpu (already included).
• Redirected to login on all pages: Login failed. Check selectors match the actual form elements. Try storeLogin approach.
• SPA navigation not working: Ensure login section is configured. Without login, page.goto() is used instead of $router.push().