microsoft--mcp-for-beginners/03-GettingStarted/06-http-streaming/solution/python

Running this sample

Here's how to run the classic HTTP streaming server and client, as well as the MCP streaming server and client using Python.

Overview

• You will set up an MCP server that streams progress notifications to the client as it processes items.
• The client will display each notification in real time.
• This guide covers prerequisites, setup, running, and troubleshooting.

Prerequisites

• Python 3.9 or newer
• The mcp Python package (install with pip install mcp)

Installation & Setup

1. Clone the repository or download the solution files.

   git clone https://github.com/microsoft/mcp-for-beginners
   

2. Create and activate a virtual environment (recommended):

   python -m venv venv
   .\venv\Scripts\Activate.ps1  # On Windows
   # or
   source venv/bin/activate      # On Linux/macOS
   

3. Install required dependencies:

   pip install "mcp[cli]" fastapi requests
   

Files

• Server: server.py
• Client: client.py

Running the Classic HTTP Streaming Server

1. Navigate to the solution directory:

   cd 03-GettingStarted/06-http-streaming/solution
   

2. Start the classic HTTP streaming server:

   python server.py
   

3. The server will start and display:

   Starting FastAPI server for classic HTTP streaming...
   INFO:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
   

Running the Classic HTTP Streaming Client

1. Open a new terminal (activate the same virtual environment and directory):

   cd 03-GettingStarted/06-http-streaming/solution
   python client.py
   

2. You should see streamed messages printed sequentially:

   Running classic HTTP streaming client...
   Connecting to http://localhost:8000/stream with message: hello
   --- Streaming Progress ---
   Processing file 1/3...
   Processing file 2/3...
   Processing file 3/3...
   Here's the file content: hello
   --- Stream Ended ---
   

Running the MCP Streaming Server

1. Navigate to the solution directory:

   cd 03-GettingStarted/06-http-streaming/solution
   

2. Start the MCP server with the streamable-http transport:

   python server.py mcp
   

3. The server will start and display:

   Starting MCP server with streamable-http transport...
   INFO:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
   

Running the MCP Streaming Client

1. Open a new terminal (activate the same virtual environment and directory):

   cd 03-GettingStarted/06-http-streaming/solution
   python client.py mcp
   

2. You should see notifications printed in real time as the server processes each item:

   Running MCP client...
   Starting client...
   Session ID before init: None
   Session ID after init: a30ab7fca9c84f5fa8f5c54fe56c9612
   Session initialized, ready to call tools.
   Received message: root=LoggingMessageNotification(...)
   NOTIFICATION: root=LoggingMessageNotification(...)
   ...
   Tool result: meta=None content=[TextContent(type='text', text='Processed files: file_1.txt, file_2.txt, file_3.txt | Message: hello from client')]
   

Key Implementation Steps

1. Create the MCP server using FastMCP.
2. Define a tool that processes a list and sends notifications using ctx.info() or ctx.log().
3. Run the server with transport="streamable-http".
4. Implement a client with a message handler to display notifications as they arrive.

Code Walkthrough

• The server uses async functions and the MCP context to send progress updates.
• The client implements an async message handler to print notifications and the final result.

Tips & Troubleshooting

• Use async/await for non-blocking operations.
• Always handle exceptions in both server and client for robustness.
• Test with multiple clients to observe real-time updates.
• If you encounter errors, check your Python version and ensure all dependencies are installed.