Azure Event Grid: Real‑time Event Routing for Cloud Services

Azure Event Grid is a fully managed event routing service that enables you to build event‑driven, serverless applications at massive scale. It supports a variety of sources and handlers, from Azure services to custom topics, allowing you to react to events in near real‑time.

Key Features

• Built‑in support for Azure services (Storage, Media Services, Key Vault, etc.)
• High throughput – up to 1 million events per second per topic
• Serverless subscription model with durable retry policies
• Advanced filtering on event type and subject
• Support for custom events and schemas

Sample Code

Publish an event to a custom topic using the azure-eventgrid SDK for JavaScript:

import { EventGridPublisherClient, AzureKeyCredential } from "@azure/eventgrid";

const endpoint = "https://<topic-name>.eventgrid.azure.net/api/events";
const key = "<access-key>";
const client = new EventGridPublisherClient(endpoint, new AzureKeyCredential(key));

async function publishEvent() {
  const events = [
    {
      id: crypto.randomUUID(),
      subject: "Demo/Topic",
      dataVersion: "1.0",
      eventType: "Demo.Event",
      data: { message: "Hello, Event Grid!" }
    }
  ];
  await client.send(events);
  console.log("Event published");
}

publishEvent();

Best Practices

When designing Event Grid solutions, consider the following:

• Use immutable event schema versions.
• Leverage dead‑lettering to capture failed deliveries.
• Implement subject hierarchy for fine‑grained filtering.
• Monitor metrics via Azure Monitor to detect throttling.