Build SSE in Python (FastAPI)
We’re building a Server-Sent Events (SSE) demo using FastAPI. This example streams messages to a browser immediately and reliably. 1️⃣ Dependencies Install the required packages: pip install fastap...
Source: DEV Community
We’re building a Server-Sent Events (SSE) demo using FastAPI. This example streams messages to a browser immediately and reliably. 1️⃣ Dependencies Install the required packages: pip install fastapi uvicorn Optional (for HTML rendering if needed): pip install jinja2 2️⃣ Python Code (SSE + HTML) Save this as main.py: from fastapi import FastAPI from fastapi.responses import StreamingResponse, HTMLResponse import time app = FastAPI() # SSE generator def event_generator(): for i in range(1, 6): yield f"data: Message {i}\n\n" # Each message ends with two newlines time.sleep(1) # simulate delay # SSE endpoint @app.get("/events") async def sse(): return StreamingResponse(event_generator(), media_type="text/event-stream") # Serve HTML page for testing @app.get("/") async def index(): return HTMLResponse(""" <!DOCTYPE html> <html> <body> <h1>SSE Test</h1> <ul id="messages"></ul> <script> const source = new EventSource("/events"); const messages =
