# asyncapi.py
from pydantic import BaseModel, Field
from datetime import datetime
from asyncapi_eventrouter import Application

asyncapi_app = Application()

class LightMeasured(BaseModel):
    id: int = Field(..., gte=0, description="ID of the streetlight.")
    lumens: int = Field(..., gte=0, description="Light intensity measured in lumens.")
    sentAt: datetime = Field(..., description="Date and time when the message was sent.")

@asyncapi_app.subscribe(channel_name="light/measured",
                        event_name="LightMeasured")
async def record_measurement(measurement: LightMeasured):
    # record to db or take some other action
    return {'received': datetime.now()}

# main.py
from fastapi import FastAPI, WebSocket
from asyncapi import asyncapi_app

app = FastAPI()

@app.websocket('/ws')
async def ws(websocket: Websocket):
    await ws.accept()
    while True:
        content = await websocket.receive_text()
        response = await asyncapi_app.process(content)
        await websocket.send_json(response)

@app.get('/ws-schema')
async def ws_schema():
    return asyncapi_app.schema()

# client.py
import asyncio
import json
from datetime import datetime

import websockets

async def send_measurement():
    data = {"id": 123, "lumens": 42, "sentAt": datetime.now().isoformat()}
    event = {"channel": "light/measured", "event": "LightMeasured", "data": data}
    async with websockets.connect("ws://localhost:8000/ws") as ws:
        await ws.send(json.dumps(event))

if __name__ == '__main__':
    asyncio.run(send_measurement())

from asyncapi import asyncapi_app
import yaml

print(yaml.dump(asyncapi_app.schema())

asyncapi: 2.2.0
channels:
  light/measured:
    publish:
      LightMeasured:
        payload:
          properties:
            id:
              description: ID of the streetlight.
              gte: 0
              title: Id
              type: integer
            lumens:
              description: Light intensity measured in lumens.
              gte: 0
              title: Lumens
              type: integer
            sentAt:
              description: Date and time when the message was sent.
              format: date-time
              title: Sentat
              type: string
          required:
          - id
          - lumens
          - sentAt
          title: LightMeasured
          type: object