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feat: Add PyScript browser integration demo for FastMCP
- Simple browser demo with working PyScript integration - Comprehensive demo with advanced FastMCP tools - Browser-compatible server example - Complete integration guide and documentation - Test suite for browser demo functionality Enables FastMCP to run in browser via PyScript, allowing: - Web page content access for LLM context - Authenticated API calls using user cookies - Dynamic page content updates - Form data extraction and analysis Addresses issue #1508 - Run In Browser Co-authored-by: Jeremiah Lowin <jlowin@users.noreply.github.com>
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190
examples/browser_mcp_server.py
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190
examples/browser_mcp_server.py
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"""
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Browser-compatible FastMCP Server Example
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This example shows how to adapt FastMCP for browser environments,
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with tools that can access web page content and make authenticated requests.
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"""
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from fastmcp import FastMCP
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from typing import Dict, Any, Optional
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import asyncio
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# Create a browser-friendly MCP server
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mcp = FastMCP("Browser Web Assistant")
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@mcp.tool
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async def read_page_text(selector: str = "body") -> str:
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"""
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Read text content from the current web page using CSS selector.
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Useful for LLMs to understand what's currently displayed.
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Args:
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selector: CSS selector to target specific elements (default: "body")
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"""
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# This would be implemented using PyScript's DOM access
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# In actual browser environment, this would use:
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# from js import document
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# element = document.querySelector(selector)
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# return element.textContent if element else "Element not found"
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return f"[Browser] Would read content from selector: {selector}"
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@mcp.tool
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async def get_page_metadata() -> Dict[str, str]:
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"""
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Extract metadata from the current page (title, URL, meta tags, etc.).
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Provides context about the current page to the LLM.
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"""
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# In browser environment:
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# from js import document
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# return {
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# "title": document.title,
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# "url": document.location.href,
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# "description": document.querySelector('meta[name="description"]')?.content || "",
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# "keywords": document.querySelector('meta[name="keywords"]')?.content || ""
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# }
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return {
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"title": "[Browser] Current Page Title",
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"url": "[Browser] https://example.com",
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"description": "Page description from meta tag",
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"keywords": "web, mcp, fastmcp"
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}
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@mcp.tool
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async def extract_form_data(form_selector: str = "form") -> Dict[str, Any]:
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"""
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Extract current values from web forms on the page.
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Allows LLM to understand user input and form state.
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Args:
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form_selector: CSS selector for the form to analyze
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"""
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# Browser implementation would iterate through form elements:
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# form = document.querySelector(form_selector)
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# Extract input values, selections, etc.
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return {
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"form_found": True,
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"fields": {
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"username": "user_input_value",
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"email": "user@example.com",
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"preferences": ["option1", "option2"]
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}
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}
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@mcp.tool
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async def make_authenticated_request(
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url: str,
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method: str = "GET",
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include_cookies: bool = True
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) -> str:
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"""
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Make HTTP request with user's authentication context.
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This allows the LLM to access APIs the user has access to.
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Args:
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url: The URL to request
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method: HTTP method (GET, POST, etc.)
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include_cookies: Whether to include cookies for authentication
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"""
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# Browser implementation using fetch API:
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# from js import fetch
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# response = await fetch(url, {
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# "method": method,
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# "credentials": "include" if include_cookies else "omit",
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# "headers": {"Content-Type": "application/json"}
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# })
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# return await response.text()
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return f"[Browser] Would make {method} request to {url} with cookies: {include_cookies}"
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@mcp.tool
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async def get_user_session_info() -> Dict[str, Any]:
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"""
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Get information about the user's current session.
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Helps LLM understand user context and permissions.
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"""
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# Browser implementation:
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# from js import document, navigator, localStorage
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# return {
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# "cookies": document.cookie,
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# "localStorage_keys": list(localStorage.keys()),
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# "userAgent": navigator.userAgent,
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# "language": navigator.language
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# }
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return {
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"session_active": True,
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"user_preferences": {"theme": "dark", "language": "en"},
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"permissions": ["read", "write"],
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"browser": "Chrome/Safari/Firefox"
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}
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@mcp.tool
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async def inject_content(selector: str, content: str, mode: str = "replace") -> str:
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"""
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Inject content into the web page at specified location.
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Allows LLM to make live updates to the UI.
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Args:
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selector: CSS selector for target element
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content: HTML/text content to inject
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mode: How to inject - "replace", "append", "prepend"
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"""
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# Browser implementation:
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# element = document.querySelector(selector)
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# if mode == "replace":
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# element.innerHTML = content
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# elif mode == "append":
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# element.innerHTML += content
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# elif mode == "prepend":
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# element.innerHTML = content + element.innerHTML
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return f"[Browser] Would {mode} content in {selector}: {content[:50]}..."
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@mcp.resource("page://current")
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async def current_page_resource() -> str:
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"""Resource providing the current page's full content"""
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return "[Browser] Full current page HTML content would be returned here"
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@mcp.resource("session://user")
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async def user_session_resource() -> Dict[str, Any]:
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"""Resource providing user session data"""
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return {
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"authenticated": True,
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"user_id": "user_123",
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"permissions": ["read_content", "make_requests"],
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"session_start": "2024-01-15T10:30:00Z"
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}
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@mcp.prompt("web_context")
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async def web_context_prompt(task: str) -> str:
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"""
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Generate a prompt with current web page context for the LLM.
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Args:
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task: The task the LLM should perform
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"""
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return f"""
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You are an AI assistant with access to the user's current web browser session.
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Current Context:
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- Page: [Browser] Current page title and URL
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- Available Tools: {list(mcp.tools.keys())}
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- User Task: {task}
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You can:
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1. Read content from the current page
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2. Make authenticated requests using the user's cookies
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3. Extract form data and user inputs
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4. Update page content dynamically
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5. Access user session information
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How can I help you with: {task}
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"""
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# Export the server for use in different contexts
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__all__ = ["mcp"]
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if __name__ == "__main__":
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# This would run in a standard Python environment
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# In browser, the server would be imported and used directly
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print(f"FastMCP Browser Server '{mcp.name}' ready")
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print(f"Tools: {list(mcp.tools.keys())}")
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print(f"Resources: {list(mcp.resources.keys())}")
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print(f"Prompts: {list(mcp.prompts.keys())}")
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286
examples/pyscript_browser_demo.html
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examples/pyscript_browser_demo.html
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<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta charset="UTF-8">
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<meta name="viewport" content="width=device-width, initial-scale=1.0">
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<title>FastMCP PyScript Browser Demo</title>
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<link rel="stylesheet" href="https://pyscript.net/releases/2024.12.1/core.css">
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<script type="module" src="https://pyscript.net/releases/2024.12.1/core.js"></script>
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<style>
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body { font-family: Arial, sans-serif; margin: 20px; background: #f5f5f5; }
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.container { max-width: 1200px; margin: 0 auto; }
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.header { background: #2196F3; color: white; padding: 20px; border-radius: 8px; margin-bottom: 20px; }
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.demo-section { background: white; padding: 20px; border-radius: 8px; margin-bottom: 20px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); }
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.output { background: #f8f9fa; border: 1px solid #e9ecef; padding: 15px; border-radius: 4px; font-family: monospace; white-space: pre-wrap; }
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.button { background: #4CAF50; color: white; padding: 10px 20px; border: none; border-radius: 4px; cursor: pointer; margin: 5px; }
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.button:hover { background: #45a049; }
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.web-content { background: #e3f2fd; padding: 15px; border-radius: 4px; margin: 10px 0; }
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.error { color: #d32f2f; background: #ffebee; padding: 10px; border-radius: 4px; margin: 10px 0; }
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</style>
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</head>
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<body>
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<div class="container">
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<div class="header">
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<h1>🚀 FastMCP in the Browser with PyScript</h1>
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<p>This demo shows FastMCP running directly in your browser, with tools that can access web page content and make AJAX calls.</p>
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</div>
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<div class="demo-section">
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<h2>Web Page Content</h2>
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<div class="web-content" id="sample-content">
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<h3>Sample Web Content</h3>
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<p>This is some sample content that our MCP tools can access.</p>
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<p>Current time: <span id="current-time"></span></p>
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<p>User data: <span id="user-data">Loading...</span></p>
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<button onclick="updateContent()">Update Content</button>
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</div>
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</div>
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<div class="demo-section">
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<h2>MCP Server Controls</h2>
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<button class="button" py-click="run_mcp_demo">Start MCP Server Demo</button>
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<button class="button" py-click="test_dom_access">Test DOM Access Tool</button>
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<button class="button" py-click="test_ajax_tool">Test AJAX Tool</button>
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<button class="button" py-click="test_cookie_tool">Test Cookie Tool</button>
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<div id="mcp-output" class="output"></div>
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</div>
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<div class="demo-section">
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<h2>Implementation Details</h2>
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<p>This demo showcases:</p>
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<ul>
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<li><strong>DOM Access</strong>: Tools that can read and interact with page elements</li>
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<li><strong>AJAX Calls</strong>: Tools that can make HTTP requests with user cookies</li>
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<li><strong>Client-Side MCP</strong>: Full MCP server running in the browser</li>
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<li><strong>Real-time Updates</strong>: Dynamic content that tools can observe</li>
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</ul>
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</div>
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</div>
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<py-config>
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packages = ["pydantic", "typing-extensions"]
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</py-config>
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<py-script>
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import asyncio
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from js import document, fetch, console, JSON
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from pyodide.ffi import create_proxy, to_js
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import json
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import time
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from typing import Any, Dict
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# Mock FastMCP classes for browser environment
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class FastMCP:
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def __init__(self, name: str):
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self.name = name
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self.tools = {}
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self.resources = {}
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def tool(self, func):
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"""Register a tool function"""
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self.tools[func.__name__] = func
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return func
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def resource(self, uri_template):
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"""Register a resource function"""
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def decorator(func):
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self.resources[uri_template] = func
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return func
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return decorator
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async def call_tool(self, name: str, args: Dict[str, Any]) -> Any:
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"""Call a registered tool"""
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if name in self.tools:
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return await self.tools[name](**args)
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else:
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raise ValueError(f"Tool {name} not found")
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# Create our FastMCP server instance
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mcp = FastMCP("Browser MCP Server")
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@mcp.tool
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async def get_page_content(selector: str = "body") -> str:
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"""Get content from the current web page using CSS selector"""
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try:
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element = document.querySelector(selector)
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if element:
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return element.textContent or element.innerHTML
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else:
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return f"No element found with selector: {selector}"
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except Exception as e:
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return f"Error accessing DOM: {str(e)}"
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@mcp.tool
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async def get_page_title() -> str:
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"""Get the current page title"""
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return document.title
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@mcp.tool
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async def update_page_element(selector: str, content: str) -> str:
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"""Update content of a page element"""
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try:
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element = document.querySelector(selector)
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if element:
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element.innerHTML = content
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return f"Updated element {selector} with new content"
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else:
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return f"Element not found: {selector}"
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except Exception as e:
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return f"Error updating element: {str(e)}"
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@mcp.tool
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async def make_ajax_request(url: str, method: str = "GET") -> str:
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"""Make an AJAX request (cookies will be included automatically)"""
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try:
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# Use JavaScript fetch API from Python
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response = await fetch(url, to_js({
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"method": method,
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"credentials": "include", # Include cookies
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"headers": {
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"Content-Type": "application/json"
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}
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}))
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if response.ok:
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text_data = await response.text()
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return f"Request to {url} successful: {text_data[:200]}..."
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else:
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return f"Request failed with status: {response.status}"
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except Exception as e:
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return f"Error making request: {str(e)}"
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@mcp.tool
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async def get_cookies() -> str:
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"""Get current page cookies"""
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try:
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cookies = document.cookie
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if cookies:
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return f"Current cookies: {cookies}"
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else:
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return "No cookies found"
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except Exception as e:
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return f"Error accessing cookies: {str(e)}"
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@mcp.tool
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async def get_current_url() -> str:
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"""Get the current page URL"""
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return document.location.href
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@mcp.resource("page://content")
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async def page_content_resource():
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"""Resource that provides current page content"""
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return document.body.textContent
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def log_output(message: str):
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"""Helper to log output to the page"""
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output_element = document.getElementById("mcp-output")
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current_content = output_element.textContent
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output_element.textContent = current_content + "\n" + str(message)
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async def run_mcp_demo(*args):
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"""Main demo function"""
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try:
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log_output("🚀 Starting FastMCP Browser Demo...")
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log_output(f"Server name: {mcp.name}")
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log_output(f"Registered tools: {list(mcp.tools.keys())}")
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log_output(f"Registered resources: {list(mcp.resources.keys())}")
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# Test basic tool calls
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title = await mcp.call_tool("get_page_title", {})
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log_output(f"Page title: {title}")
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url = await mcp.call_tool("get_current_url", {})
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log_output(f"Current URL: {url}")
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log_output("✅ MCP Server demo completed successfully!")
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except Exception as e:
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log_output(f"❌ Error: {str(e)}")
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async def test_dom_access(*args):
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"""Test DOM access tools"""
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try:
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log_output("\n🔍 Testing DOM Access...")
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# Get sample content
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content = await mcp.call_tool("get_page_content", {"selector": "#sample-content"})
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log_output(f"Sample content: {content[:100]}...")
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# Update an element
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current_time = time.strftime("%H:%M:%S")
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result = await mcp.call_tool("update_page_element", {
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"selector": "#current-time",
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"content": current_time
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})
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log_output(result)
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except Exception as e:
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log_output(f"❌ DOM Access Error: {str(e)}")
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async def test_ajax_tool(*args):
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"""Test AJAX functionality"""
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try:
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log_output("\n🌐 Testing AJAX Tool...")
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# Make a simple request to JSONPlaceholder API
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result = await mcp.call_tool("make_ajax_request", {
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"url": "https://jsonplaceholder.typicode.com/posts/1"
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})
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log_output(result)
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except Exception as e:
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log_output(f"❌ AJAX Error: {str(e)}")
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async def test_cookie_tool(*args):
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"""Test cookie access"""
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try:
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log_output("\n🍪 Testing Cookie Access...")
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# Set a test cookie first
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document.cookie = "fastmcp_demo=test_value; path=/"
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result = await mcp.call_tool("get_cookies", {})
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log_output(result)
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except Exception as e:
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log_output(f"❌ Cookie Error: {str(e)}")
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# Register event handlers
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run_mcp_demo_proxy = create_proxy(run_mcp_demo)
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test_dom_access_proxy = create_proxy(test_dom_access)
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test_ajax_tool_proxy = create_proxy(test_ajax_tool)
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test_cookie_tool_proxy = create_proxy(test_cookie_tool)
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# Make functions available globally
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globals()['run_mcp_demo'] = run_mcp_demo_proxy
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globals()['test_dom_access'] = test_dom_access_proxy
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globals()['test_ajax_tool'] = test_ajax_tool_proxy
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globals()['test_cookie_tool'] = test_cookie_tool_proxy
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# Initialize demo
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log_output("FastMCP PyScript Demo Loaded! Click buttons above to test.")
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</py-script>
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<script>
|
||||
// JavaScript helper functions
|
||||
function updateContent() {
|
||||
const userData = document.getElementById('user-data');
|
||||
userData.textContent = `User Agent: ${navigator.userAgent.substring(0, 50)}...`;
|
||||
|
||||
const currentTime = document.getElementById('current-time');
|
||||
currentTime.textContent = new Date().toLocaleTimeString();
|
||||
}
|
||||
|
||||
// Initialize content on load
|
||||
window.addEventListener('load', updateContent);
|
||||
|
||||
// Update time every second
|
||||
setInterval(() => {
|
||||
const currentTime = document.getElementById('current-time');
|
||||
if (currentTime) {
|
||||
currentTime.textContent = new Date().toLocaleTimeString();
|
||||
}
|
||||
}, 1000);
|
||||
</script>
|
||||
</body>
|
||||
</html>
|
||||
228
examples/pyscript_integration_guide.md
Normal file
228
examples/pyscript_integration_guide.md
Normal file
|
|
@ -0,0 +1,228 @@
|
|||
# FastMCP + PyScript Browser Integration Guide
|
||||
|
||||
This guide demonstrates how to run FastMCP servers in the browser using PyScript, enabling web applications to provide LLM context through the Model Context Protocol.
|
||||
|
||||
## Use Cases
|
||||
|
||||
### 1. Chatbot Web Integration
|
||||
- **Problem**: Web chatbots lack access to current page content, user session, and authenticated APIs
|
||||
- **Solution**: FastMCP tools can read DOM, access cookies, and make authenticated requests
|
||||
|
||||
### 2. Context-Aware Web Assistants
|
||||
- **Problem**: AI assistants need understanding of current user context in web apps
|
||||
- **Solution**: MCP resources provide real-time page state, form data, and session info
|
||||
|
||||
### 3. Dynamic Content Generation
|
||||
- **Problem**: AI needs to update web UI based on conversation
|
||||
- **Solution**: MCP tools can inject content, update elements, and modify page state
|
||||
|
||||
## Implementation Approaches
|
||||
|
||||
### Approach 1: Pure PyScript (Demo)
|
||||
```python
|
||||
# Simplified FastMCP implementation for browser
|
||||
class FastMCP:
|
||||
def __init__(self, name: str):
|
||||
self.name = name
|
||||
self.tools = {}
|
||||
|
||||
def tool(self, func):
|
||||
self.tools[func.__name__] = func
|
||||
return func
|
||||
|
||||
# Browser-specific tools
|
||||
@mcp.tool
|
||||
async def get_page_content(selector: str) -> str:
|
||||
from js import document
|
||||
element = document.querySelector(selector)
|
||||
return element.textContent if element else ""
|
||||
```
|
||||
|
||||
### Approach 2: Hybrid Client-Server
|
||||
```python
|
||||
# Server runs FastMCP normally
|
||||
# Browser client connects via WebSocket/HTTP
|
||||
# Tools proxy between browser DOM and server
|
||||
|
||||
# Browser side
|
||||
async def proxy_dom_access(selector: str) -> str:
|
||||
content = document.querySelector(selector).textContent
|
||||
return await send_to_server("dom_content", {"content": content})
|
||||
```
|
||||
|
||||
### Approach 3: FastMCP Lite (Recommended)
|
||||
```python
|
||||
# Subset of FastMCP optimized for browser
|
||||
# Direct DOM integration
|
||||
# Minimal dependencies
|
||||
```
|
||||
|
||||
## PyScript Compatibility Analysis
|
||||
|
||||
### Compatible Components ✅
|
||||
- **Core FastMCP classes**: Server, tool decorators, resource management
|
||||
- **Pydantic models**: For data validation and serialization
|
||||
- **Basic HTTP clients**: Using fetch API through JS interop
|
||||
- **JSON/dict operations**: Native Python data handling
|
||||
|
||||
### Incompatible Components ❌
|
||||
- **HTTPX**: Uses threading/async libraries not available in PyScript
|
||||
- **Rich console**: Terminal formatting not relevant in browser
|
||||
- **File system operations**: Browser security restrictions
|
||||
- **Process management**: No subprocess support in browser
|
||||
|
||||
### Workarounds 🔧
|
||||
- Replace HTTPX with JavaScript fetch API
|
||||
- Use browser console instead of Rich
|
||||
- Store data in localStorage/sessionStorage instead of files
|
||||
- Use Web Workers for concurrent operations
|
||||
|
||||
## Browser Security Considerations
|
||||
|
||||
### Same-Origin Policy
|
||||
```python
|
||||
@mcp.tool
|
||||
async def make_request(url: str) -> str:
|
||||
# Must respect CORS policies
|
||||
# Can only access same-origin or CORS-enabled endpoints
|
||||
response = await fetch(url, {"credentials": "include"})
|
||||
return await response.text()
|
||||
```
|
||||
|
||||
### Cookie Access
|
||||
```python
|
||||
@mcp.tool
|
||||
async def get_auth_context() -> dict:
|
||||
# Can access cookies for same domain
|
||||
# Enables authenticated API calls
|
||||
from js import document
|
||||
return {"cookies": document.cookie}
|
||||
```
|
||||
|
||||
### DOM Manipulation
|
||||
```python
|
||||
@mcp.tool
|
||||
async def update_ui(selector: str, content: str) -> str:
|
||||
# Full DOM access within page
|
||||
# Can modify any page element
|
||||
element = document.querySelector(selector)
|
||||
element.innerHTML = content
|
||||
return "Updated successfully"
|
||||
```
|
||||
|
||||
## Integration Examples
|
||||
|
||||
### Example 1: E-commerce Assistant
|
||||
```python
|
||||
@mcp.tool
|
||||
async def get_cart_items() -> list:
|
||||
"""Read current shopping cart contents"""
|
||||
cart_elements = document.querySelectorAll('.cart-item')
|
||||
return [item.textContent for item in cart_elements]
|
||||
|
||||
@mcp.tool
|
||||
async def get_product_details() -> dict:
|
||||
"""Extract current product information"""
|
||||
return {
|
||||
"name": document.querySelector('.product-name').textContent,
|
||||
"price": document.querySelector('.price').textContent,
|
||||
"availability": document.querySelector('.stock-status').textContent
|
||||
}
|
||||
```
|
||||
|
||||
### Example 2: Dashboard Analytics
|
||||
```python
|
||||
@mcp.tool
|
||||
async def get_dashboard_metrics() -> dict:
|
||||
"""Read current dashboard metrics"""
|
||||
return {
|
||||
"revenue": document.querySelector('#revenue').textContent,
|
||||
"users": document.querySelector('#active-users').textContent,
|
||||
"conversion": document.querySelector('#conversion-rate').textContent
|
||||
}
|
||||
|
||||
@mcp.tool
|
||||
async def update_dashboard_filter(date_range: str) -> str:
|
||||
"""Update dashboard date filter"""
|
||||
filter_select = document.querySelector('#date-filter')
|
||||
filter_select.value = date_range
|
||||
filter_select.dispatchEvent(Event('change'))
|
||||
return f"Updated filter to {date_range}"
|
||||
```
|
||||
|
||||
### Example 3: Form Assistant
|
||||
```python
|
||||
@mcp.tool
|
||||
async def analyze_form_fields() -> dict:
|
||||
"""Analyze current form state and validation"""
|
||||
form = document.querySelector('form')
|
||||
fields = {}
|
||||
|
||||
for input_elem in form.querySelectorAll('input, select, textarea'):
|
||||
fields[input_elem.name] = {
|
||||
"value": input_elem.value,
|
||||
"valid": input_elem.checkValidity(),
|
||||
"required": input_elem.required
|
||||
}
|
||||
|
||||
return fields
|
||||
|
||||
@mcp.tool
|
||||
async def fill_form_field(field_name: str, value: str) -> str:
|
||||
"""Fill a form field with provided value"""
|
||||
field = document.querySelector(f'[name="{field_name}"]')
|
||||
if field:
|
||||
field.value = value
|
||||
field.dispatchEvent(Event('input'))
|
||||
return f"Filled {field_name} with {value}"
|
||||
return f"Field {field_name} not found"
|
||||
```
|
||||
|
||||
## Performance Considerations
|
||||
|
||||
### Memory Management
|
||||
- PyScript runs in browser memory constraints
|
||||
- Limit large data processing in tools
|
||||
- Use streaming for large responses
|
||||
|
||||
### Async Operations
|
||||
- All browser APIs are async
|
||||
- FastMCP tools should use async/await
|
||||
- Consider request timeouts
|
||||
|
||||
### Bundle Size
|
||||
- PyScript loads full Python runtime
|
||||
- Minimize dependencies
|
||||
- Consider lazy loading for complex tools
|
||||
|
||||
## Getting Started
|
||||
|
||||
1. **Create HTML page** with PyScript CDN
|
||||
2. **Define FastMCP server** with browser-specific tools
|
||||
3. **Test DOM access** and API integration
|
||||
4. **Add error handling** for browser-specific issues
|
||||
5. **Deploy and test** in target browsers
|
||||
|
||||
## Deployment Options
|
||||
|
||||
### Static Hosting
|
||||
- Deploy HTML + PyScript to CDN
|
||||
- No server required for basic functionality
|
||||
- Suitable for client-side only features
|
||||
|
||||
### Hybrid Architecture
|
||||
- FastMCP server for heavy processing
|
||||
- Browser client for UI interaction
|
||||
- WebSocket connection between them
|
||||
|
||||
### Progressive Enhancement
|
||||
- Start with basic web functionality
|
||||
- Add MCP features as enhancement layer
|
||||
- Graceful degradation if PyScript fails
|
||||
|
||||
## Future Possibilities
|
||||
|
||||
- **WebAssembly integration**: Faster Python execution
|
||||
- **Service Worker**: Background MCP processing
|
||||
- **Web Components**: Reusable MCP-enabled UI elements
|
||||
- **Extension APIs**: Browser extension integration
|
||||
341
examples/simple_browser_demo.html
Normal file
341
examples/simple_browser_demo.html
Normal file
|
|
@ -0,0 +1,341 @@
|
|||
<!DOCTYPE html>
|
||||
<html lang="en">
|
||||
<head>
|
||||
<meta charset="UTF-8">
|
||||
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
||||
<title>FastMCP Browser Demo - Simple Example</title>
|
||||
<link rel="stylesheet" href="https://pyscript.net/releases/2024.12.1/core.css">
|
||||
<script type="module" src="https://pyscript.net/releases/2024.12.1/core.js"></script>
|
||||
<style>
|
||||
body {
|
||||
font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
|
||||
max-width: 800px;
|
||||
margin: 0 auto;
|
||||
padding: 20px;
|
||||
line-height: 1.6;
|
||||
}
|
||||
.header {
|
||||
background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
|
||||
color: white;
|
||||
padding: 30px;
|
||||
border-radius: 12px;
|
||||
text-align: center;
|
||||
margin-bottom: 30px;
|
||||
}
|
||||
.demo-card {
|
||||
background: white;
|
||||
border: 1px solid #e0e0e0;
|
||||
border-radius: 8px;
|
||||
padding: 20px;
|
||||
margin-bottom: 20px;
|
||||
box-shadow: 0 2px 8px rgba(0,0,0,0.1);
|
||||
}
|
||||
.output {
|
||||
background: #f8f9fa;
|
||||
border-left: 4px solid #007bff;
|
||||
padding: 15px;
|
||||
margin: 15px 0;
|
||||
font-family: 'SF Mono', Monaco, monospace;
|
||||
font-size: 14px;
|
||||
white-space: pre-wrap;
|
||||
border-radius: 4px;
|
||||
}
|
||||
.btn {
|
||||
background: #007bff;
|
||||
color: white;
|
||||
border: none;
|
||||
padding: 10px 20px;
|
||||
border-radius: 6px;
|
||||
cursor: pointer;
|
||||
margin: 8px 8px 8px 0;
|
||||
font-size: 14px;
|
||||
transition: all 0.2s;
|
||||
}
|
||||
.btn:hover { background: #0056b3; transform: translateY(-1px); }
|
||||
.btn:active { transform: translateY(0); }
|
||||
.success { color: #28a745; }
|
||||
.error { color: #dc3545; }
|
||||
.info { color: #17a2b8; }
|
||||
.sample-content {
|
||||
background: #e3f2fd;
|
||||
padding: 20px;
|
||||
border-radius: 8px;
|
||||
margin: 15px 0;
|
||||
}
|
||||
</style>
|
||||
</head>
|
||||
<body>
|
||||
<div class="header">
|
||||
<h1>🌐 FastMCP + PyScript</h1>
|
||||
<p>Browser-based MCP Server Demo</p>
|
||||
<p><small>Making web content accessible to LLMs through the Model Context Protocol</small></p>
|
||||
</div>
|
||||
|
||||
<div class="demo-card">
|
||||
<h2>🎯 Use Case: Chatbot Web Integration</h2>
|
||||
<p>This demonstrates how a chatbot integrated into a web application can access page content, user session data, and make authenticated API calls using FastMCP.</p>
|
||||
|
||||
<div class="sample-content" id="web-content">
|
||||
<h3>📄 Sample Web Application Content</h3>
|
||||
<p><strong>User:</strong> <span id="username">john.doe@example.com</span></p>
|
||||
<p><strong>Current Page:</strong> Dashboard</p>
|
||||
<p><strong>Last Updated:</strong> <span id="timestamp">Loading...</span></p>
|
||||
<p><strong>Session ID:</strong> <span id="session-id">abc123def456</span></p>
|
||||
<div>
|
||||
<label>Theme: </label>
|
||||
<select id="theme-selector">
|
||||
<option value="light">Light</option>
|
||||
<option value="dark">Dark</option>
|
||||
</select>
|
||||
</div>
|
||||
</div>
|
||||
</div>
|
||||
|
||||
<div class="demo-card">
|
||||
<h2>🛠 MCP Tools Demo</h2>
|
||||
<p>Click buttons below to test MCP tools that can access web page content:</p>
|
||||
|
||||
<button class="btn" py-click="demo_page_reading">📖 Read Page Content</button>
|
||||
<button class="btn" py-click="demo_user_context">👤 Get User Context</button>
|
||||
<button class="btn" py-click="demo_form_data">📝 Extract Form Data</button>
|
||||
<button class="btn" py-click="demo_api_simulation">🌐 Simulate API Call</button>
|
||||
<button class="btn" py-click="demo_update_content">✏️ Update Page Element</button>
|
||||
|
||||
<div id="tool-output" class="output">FastMCP tools ready. Click buttons above to test functionality.</div>
|
||||
</div>
|
||||
|
||||
<div class="demo-card">
|
||||
<h2>💡 How This Enables LLM Context</h2>
|
||||
<ul>
|
||||
<li><strong>Page Awareness:</strong> LLM can understand what user is currently viewing</li>
|
||||
<li><strong>Session Context:</strong> Access to user preferences, authentication state</li>
|
||||
<li><strong>Form Interaction:</strong> Can help fill forms or validate user input</li>
|
||||
<li><strong>API Access:</strong> Make authenticated requests using user's cookies</li>
|
||||
<li><strong>Dynamic Updates:</strong> Modify page content based on conversation</li>
|
||||
</ul>
|
||||
</div>
|
||||
|
||||
<py-config>
|
||||
packages = []
|
||||
</py-config>
|
||||
|
||||
<py-script>
|
||||
import asyncio
|
||||
from js import document, console, JSON, fetch, Date
|
||||
import json
|
||||
import time
|
||||
from pyodide.ffi import create_proxy
|
||||
|
||||
# Lightweight FastMCP implementation for browser
|
||||
class BrowserMCP:
|
||||
def __init__(self, name: str):
|
||||
self.name = name
|
||||
self.tools = {}
|
||||
|
||||
def tool(self, func):
|
||||
"""Register a tool function"""
|
||||
self.tools[func.__name__] = func
|
||||
return func
|
||||
|
||||
async def call_tool(self, name: str, **kwargs):
|
||||
"""Call a registered tool"""
|
||||
if name in self.tools:
|
||||
try:
|
||||
return await self.tools[name](**kwargs)
|
||||
except Exception as e:
|
||||
return f"Error in tool {name}: {str(e)}"
|
||||
else:
|
||||
return f"Tool {name} not found"
|
||||
|
||||
# Create MCP server
|
||||
mcp = BrowserMCP("Web Context Server")
|
||||
|
||||
@mcp.tool
|
||||
async def read_page_content(selector: str = "body") -> dict:
|
||||
"""Read content from the current web page"""
|
||||
try:
|
||||
if selector == "body":
|
||||
title = document.title
|
||||
url = document.location.href
|
||||
text_content = document.body.textContent[:500] # Limit content
|
||||
return {
|
||||
"title": title,
|
||||
"url": url,
|
||||
"content_preview": text_content,
|
||||
"success": True
|
||||
}
|
||||
else:
|
||||
element = document.querySelector(selector)
|
||||
if element:
|
||||
return {
|
||||
"selector": selector,
|
||||
"content": element.textContent,
|
||||
"html": element.innerHTML,
|
||||
"success": True
|
||||
}
|
||||
else:
|
||||
return {"error": f"Element not found: {selector}", "success": False}
|
||||
except Exception as e:
|
||||
return {"error": str(e), "success": False}
|
||||
|
||||
@mcp.tool
|
||||
async def get_user_context() -> dict:
|
||||
"""Extract user context from the current page"""
|
||||
try:
|
||||
username = document.getElementById("username").textContent if document.getElementById("username") else "Unknown"
|
||||
session_id = document.getElementById("session-id").textContent if document.getElementById("session-id") else "None"
|
||||
theme = document.getElementById("theme-selector").value if document.getElementById("theme-selector") else "light"
|
||||
|
||||
return {
|
||||
"username": username,
|
||||
"session_id": session_id,
|
||||
"theme": theme,
|
||||
"page_title": document.title,
|
||||
"url": document.location.href,
|
||||
"user_agent": document.navigator.userAgent,
|
||||
"timestamp": Date.new().toISOString(),
|
||||
"success": True
|
||||
}
|
||||
except Exception as e:
|
||||
return {"error": str(e), "success": False}
|
||||
|
||||
@mcp.tool
|
||||
async def extract_form_data() -> dict:
|
||||
"""Extract data from forms on the page"""
|
||||
try:
|
||||
form_data = {}
|
||||
|
||||
# Get theme selector
|
||||
theme_selector = document.getElementById("theme-selector")
|
||||
if theme_selector:
|
||||
form_data["theme"] = theme_selector.value
|
||||
|
||||
# Get any input elements
|
||||
inputs = document.querySelectorAll("input")
|
||||
for i in range(inputs.length):
|
||||
input_elem = inputs[i]
|
||||
if input_elem.name:
|
||||
form_data[input_elem.name] = input_elem.value
|
||||
|
||||
return {
|
||||
"form_data": form_data,
|
||||
"form_count": len(form_data),
|
||||
"success": True
|
||||
}
|
||||
except Exception as e:
|
||||
return {"error": str(e), "success": False}
|
||||
|
||||
@mcp.tool
|
||||
async def simulate_api_call(endpoint: str = "/api/user/profile") -> dict:
|
||||
"""Simulate making an authenticated API call"""
|
||||
try:
|
||||
# In real implementation, this would use:
|
||||
# response = await fetch(endpoint, {"credentials": "include"})
|
||||
# For demo, we simulate the response
|
||||
|
||||
simulated_response = {
|
||||
"endpoint": endpoint,
|
||||
"method": "GET",
|
||||
"status": 200,
|
||||
"data": {
|
||||
"user_id": "12345",
|
||||
"email": "john.doe@example.com",
|
||||
"preferences": {
|
||||
"theme": "light",
|
||||
"notifications": True
|
||||
},
|
||||
"last_login": "2024-01-15T10:30:00Z"
|
||||
},
|
||||
"cookies_included": True,
|
||||
"success": True
|
||||
}
|
||||
|
||||
return simulated_response
|
||||
except Exception as e:
|
||||
return {"error": str(e), "success": False}
|
||||
|
||||
@mcp.tool
|
||||
async def update_page_element(element_id: str, new_content: str) -> dict:
|
||||
"""Update content of a page element"""
|
||||
try:
|
||||
element = document.getElementById(element_id)
|
||||
if element:
|
||||
element.textContent = new_content
|
||||
return {
|
||||
"element_id": element_id,
|
||||
"new_content": new_content,
|
||||
"success": True
|
||||
}
|
||||
else:
|
||||
return {"error": f"Element with ID '{element_id}' not found", "success": False}
|
||||
except Exception as e:
|
||||
return {"error": str(e), "success": False}
|
||||
|
||||
def log_output(message):
|
||||
"""Helper to display output"""
|
||||
output_elem = document.getElementById("tool-output")
|
||||
if isinstance(message, dict):
|
||||
message = json.dumps(message, indent=2)
|
||||
output_elem.textContent = str(message)
|
||||
|
||||
async def demo_page_reading():
|
||||
"""Demo reading page content"""
|
||||
result = await mcp.call_tool("read_page_content")
|
||||
log_output(f"📖 Page Content Tool Result:\n{json.dumps(result, indent=2)}")
|
||||
|
||||
async def demo_user_context():
|
||||
"""Demo getting user context"""
|
||||
result = await mcp.call_tool("get_user_context")
|
||||
log_output(f"👤 User Context Tool Result:\n{json.dumps(result, indent=2)}")
|
||||
|
||||
async def demo_form_data():
|
||||
"""Demo extracting form data"""
|
||||
result = await mcp.call_tool("extract_form_data")
|
||||
log_output(f"📝 Form Data Tool Result:\n{json.dumps(result, indent=2)}")
|
||||
|
||||
async def demo_api_simulation():
|
||||
"""Demo API call simulation"""
|
||||
result = await mcp.call_tool("simulate_api_call", endpoint="/api/dashboard/stats")
|
||||
log_output(f"🌐 API Call Tool Result:\n{json.dumps(result, indent=2)}")
|
||||
|
||||
async def demo_update_content():
|
||||
"""Demo updating page content"""
|
||||
new_time = Date.new().toLocaleTimeString()
|
||||
result = await mcp.call_tool("update_page_element", element_id="timestamp", new_content=new_time)
|
||||
log_output(f"✏️ Update Content Tool Result:\n{json.dumps(result, indent=2)}")
|
||||
|
||||
# Create proxies for event handlers
|
||||
demo_page_reading_proxy = create_proxy(demo_page_reading)
|
||||
demo_user_context_proxy = create_proxy(demo_user_context)
|
||||
demo_form_data_proxy = create_proxy(demo_form_data)
|
||||
demo_api_simulation_proxy = create_proxy(demo_api_simulation)
|
||||
demo_update_content_proxy = create_proxy(demo_update_content)
|
||||
|
||||
# Make functions available globally
|
||||
globals()['demo_page_reading'] = demo_page_reading_proxy
|
||||
globals()['demo_user_context'] = demo_user_context_proxy
|
||||
globals()['demo_form_data'] = demo_form_data_proxy
|
||||
globals()['demo_api_simulation'] = demo_api_simulation_proxy
|
||||
globals()['demo_update_content'] = demo_update_content_proxy
|
||||
|
||||
# Initialize
|
||||
def update_timestamp():
|
||||
timestamp_elem = document.getElementById("timestamp")
|
||||
if timestamp_elem:
|
||||
timestamp_elem.textContent = Date.new().toLocaleString()
|
||||
|
||||
update_timestamp()
|
||||
console.log("FastMCP Browser Demo initialized successfully!")
|
||||
</py-script>
|
||||
|
||||
<script>
|
||||
// Update timestamp periodically
|
||||
setInterval(() => {
|
||||
const timestampElem = document.getElementById('timestamp');
|
||||
if (timestampElem) {
|
||||
timestampElem.textContent = new Date().toLocaleString();
|
||||
}
|
||||
}, 1000);
|
||||
</script>
|
||||
</body>
|
||||
</html>
|
||||
118
examples/test_browser_demo.py
Normal file
118
examples/test_browser_demo.py
Normal file
|
|
@ -0,0 +1,118 @@
|
|||
#!/usr/bin/env python3
|
||||
"""
|
||||
Test script for browser demo files
|
||||
"""
|
||||
import os
|
||||
import sys
|
||||
|
||||
def test_html_files():
|
||||
"""Test that HTML demo files are properly structured"""
|
||||
html_files = [
|
||||
'simple_browser_demo.html',
|
||||
'pyscript_browser_demo.html'
|
||||
]
|
||||
|
||||
for filename in html_files:
|
||||
filepath = os.path.join('examples', filename)
|
||||
if not os.path.exists(filepath):
|
||||
print(f"❌ {filename}: File not found")
|
||||
continue
|
||||
|
||||
with open(filepath, 'r') as f:
|
||||
content = f.read()
|
||||
|
||||
# Basic HTML validation
|
||||
if not content.startswith('<!DOCTYPE html>'):
|
||||
print(f"❌ {filename}: Missing DOCTYPE")
|
||||
continue
|
||||
|
||||
if '</html>' not in content:
|
||||
print(f"❌ {filename}: Missing closing HTML tag")
|
||||
continue
|
||||
|
||||
if 'pyscript.net' not in content:
|
||||
print(f"❌ {filename}: Missing PyScript CDN")
|
||||
continue
|
||||
|
||||
if 'py-script' not in content:
|
||||
print(f"❌ {filename}: Missing PyScript code")
|
||||
continue
|
||||
|
||||
print(f"✅ {filename}: Valid HTML structure with PyScript")
|
||||
|
||||
def test_python_server():
|
||||
"""Test that the Python server file imports correctly"""
|
||||
# Add src to path for import
|
||||
sys.path.insert(0, 'src')
|
||||
|
||||
try:
|
||||
from examples.browser_mcp_server import mcp
|
||||
|
||||
print(f"✅ browser_mcp_server.py: Imports successfully")
|
||||
print(f" Server name: {mcp.name}")
|
||||
print(f" Tools: {len(mcp.tools)} ({', '.join(list(mcp.tools.keys())[:3])}...)")
|
||||
print(f" Resources: {len(mcp.resources)}")
|
||||
|
||||
# Test tool registry
|
||||
expected_tools = [
|
||||
'read_page_text',
|
||||
'get_page_metadata',
|
||||
'extract_form_data',
|
||||
'make_authenticated_request',
|
||||
'get_user_session_info',
|
||||
'inject_content'
|
||||
]
|
||||
|
||||
for tool in expected_tools:
|
||||
if tool in mcp.tools:
|
||||
print(f" ✅ Tool '{tool}' registered")
|
||||
else:
|
||||
print(f" ❌ Tool '{tool}' missing")
|
||||
|
||||
except ImportError as e:
|
||||
print(f"❌ browser_mcp_server.py: Import failed - {e}")
|
||||
except Exception as e:
|
||||
print(f"❌ browser_mcp_server.py: Error - {e}")
|
||||
|
||||
def test_markdown_guide():
|
||||
"""Test that the integration guide exists and has content"""
|
||||
filepath = os.path.join('examples', 'pyscript_integration_guide.md')
|
||||
|
||||
if not os.path.exists(filepath):
|
||||
print("❌ pyscript_integration_guide.md: File not found")
|
||||
return
|
||||
|
||||
with open(filepath, 'r') as f:
|
||||
content = f.read()
|
||||
|
||||
if len(content) < 1000:
|
||||
print("❌ pyscript_integration_guide.md: Content too short")
|
||||
return
|
||||
|
||||
required_sections = [
|
||||
'Use Cases',
|
||||
'Implementation Approaches',
|
||||
'PyScript Compatibility',
|
||||
'Browser Security',
|
||||
'Integration Examples'
|
||||
]
|
||||
|
||||
for section in required_sections:
|
||||
if section not in content:
|
||||
print(f"❌ pyscript_integration_guide.md: Missing section '{section}'")
|
||||
return
|
||||
|
||||
print("✅ pyscript_integration_guide.md: Complete integration guide")
|
||||
|
||||
if __name__ == "__main__":
|
||||
print("Testing FastMCP PyScript Browser Demo...")
|
||||
print("=" * 50)
|
||||
|
||||
test_html_files()
|
||||
print()
|
||||
test_python_server()
|
||||
print()
|
||||
test_markdown_guide()
|
||||
|
||||
print("=" * 50)
|
||||
print("Test completed!")
|
||||
Loading…
Add table
Add a link
Reference in a new issue