Add Sanic Example

examples/sanic/README.md

@@ -0,0 +1,32 @@
+# Sanic Example
+
+This example demonstrates how to use HMR with a Sanic application.
+
+## How to Run
+
+After installing dependencies, run the following command in this directory:
+
+```sh
+hmr app.py
+```
+
+This will start a Sanic development server with HOT-reloading enabled.
+
+## What to Observe
+
+Once the server is running, you can access the application at `http://localhost:8000`.
+
+- Visit `http://localhost:8000/a` and `http://localhost:8000/b`.
+- Try modifying `b.py` and refresh the browser to see the changes applied instantly (without rerunning `sleep(1)` in `a.py`).
+- Everything else should work as expected too. You will find your development experience much smoother than just using `sanic app:app --dev`.
+
+> [!NOTE]
+> Unlike [the FastAPI example](../fastapi/), we haven't implement a separate integration for Sanic.
+> If you know Sanic well, you are welcome to contribute an integration similar to `uvicorn-hmr`.
+
+## Available Endpoints
+
+- `/` - Main app endpoint with route information
+- `/a` - Blueprint A endpoint  
+- `/b` - Blueprint B endpoint
+- `/b/test` - Test endpoint from Blueprint B

examples/sanic/a.py

@@ -0,0 +1,15 @@
+from time import sleep
+
+from sanic import Blueprint
+from sanic.response import json
+
+a = Blueprint("a", url_prefix="/a")
+
+
+sleep(1)
+print("slow module a.py imported")
+
+
+@a.route("/")
+async def index(_):
+    return json({"message": "Hello from a.py!"})

examples/sanic/app.py

@@ -0,0 +1,24 @@
+import time
+
+from a import a
+from b import b
+from sanic import Sanic
+from sanic.response import json
+
+# Create a dynamic app name to avoid conflicts during HMR
+app_name = f"SanicExample_{int(time.time())}"
+app = Sanic(app_name)
+
+app.blueprint(a)
+app.blueprint(b)
+
+
+@app.route("/")
+async def index(_):
+    return json({"message": "Hello from main Sanic app!", "routes": ["/a", "/b", "/b/test"]})
+
+
+if __name__ == "__main__":
+    from start import start_server
+
+    start_server(app)

examples/sanic/b.py

@@ -0,0 +1,14 @@
+from sanic import Blueprint
+from sanic.response import json
+
+b = Blueprint("b", url_prefix="/b")
+
+
+@b.route("/")
+async def index(_):
+    return json({"message": "Hello from b.py! (FINAL HMR TEST)", "data": "HMR is working perfectly with Sanic!"})
+
+
+@b.route("/test")
+async def test(_):
+    return json({"message": "Test endpoint from b.py", "status": "working", "hmr": "fully operational"})

examples/sanic/pyproject.toml

@@ -0,0 +1,11 @@
+[project]
+name = "sanic-example"
+version = "0"
+requires-python = ">=3.12"
+dependencies = [
+    "sanic~=24.6.0",
+    "hmr~=0.6.0",
+]
+
+[tool.uv]
+package = false

examples/sanic/start.py

@@ -0,0 +1,60 @@
+"""
+You don't need to understand what this code does.
+
+This file implements a simple function to start a Sanic server with HMR support.
+
+To use it, just copy this file to your project and call the `start_server` function with your Sanic app instance.
+And then run this file with `hmr path/to/this/file.py`.
+
+We haven't implement a separate integration for Sanic.
+So you need to use this function to start the server with HMR support.
+"""
+
+from atexit import register, unregister
+from multiprocessing import Process
+from typing import cast
+
+from sanic import Sanic
+
+
+class ServerProcess(Process):
+    def __init__(self, app: Sanic):
+        super().__init__(daemon=True)
+        self.app = app
+
+    def run(self):
+        # Run in a separate process to avoid signal conflicts
+        self.app.run(host="localhost", port=8000, debug=False, auto_reload=False, single_process=True)
+
+    def shutdown(self):
+        if self.is_alive():
+            self.terminate()
+            self.join(timeout=1)
+            if self.is_alive():
+                self.kill()
+
+
+def start_server(app: Sanic):
+    global server
+
+    print("* Running on http://localhost:8000")
+
+    if server := cast("ServerProcess | None", globals().get("server")):
+        unregister(server.shutdown)
+        server.shutdown()
+
+    server = ServerProcess(app)
+    server.start()
+    register(server.shutdown)
+
+
+if __name__ == "__main__":
+    from app import app
+
+    start_server(app)
+
+
+if __name__ == "__main__":
+    from app import app
+
+    start_server(app)