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Deploying a Realtime App

This is a simple example of a realtime streaming app. When deployed, this app will be exposed as a public websocket endpoint. The realtime handler accepts a single parameter, called event, with the event payload.
The realtime decorator is an abstraction above asgi.This means that additional parameters in asgi, such as concurrent_requests can be used too.
app.py
from beam import realtime


@realtime(
    cpu=1,
    memory="1Gi",
    concurrent_requests=10, # Process 10 requests at a time 
    authorized=False, # Don't require auth to invoke 
)
def stream(event):
    # Echo back the event payload sent to the websocket
    return {"response": event}
This app can be deployed in traditional Beam fashion: 
beam deploy app.py:stream

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Streaming Responses from the Client

Realtime Endpoints can be connected to from any websocket client.
  • Beam Javascript SDK
  • Javascript
The code below uses the Beam Javascript SDK to send requests to the realtime app.Make sure to add an .env file to your project with your BEAM_DEPLOYMENT_ID and BEAM_TOKEN:
client.js
import beam from "@beamcloud/beam-js";

const streamResponse = async () => {
  const client = await beam.init(process.env.BEAM_TOKEN);
  const deployment = await client.deployments.get({ id: process.env.BEAM_DEPLOYMENT_ID });

  const connection = await deployment.realtime();
  
  const payload = {
    "event": "Echo this back",
  }

  connection.onmessage = (message) => {
      console.log(`🎉 Response: ${message.data}`);
  };

  connection.send(JSON.stringify(payload));

  setTimeout(() => {
    connection.close();
  }, 1000);
};

streamResponse();
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