Reactive Architecture with Azure Event Grid

Reactive, event-driven architecture
Deep dive into Azure Event Grid

“Take a ride on the grid” demo series

📈 Why Event Thinking Matters

Enterprises should embrace “event thinking” as part of their digital strategy.

By 2020, event-sourced, real-time situational awareness will be required for 80% of digital business solutions, and 80% of new business ecosystems will require event processing. — Gartner Top 10 Strategic Technology Trends (2018)

Events Tell a Story

Change is captured in an event

A series of events captures behaviour

Event streams capture patterns

Together, they tell the narrative of the system

⚡ What Is a Reactive Architecture?

A system design approach focused on:

  • Responsiveness
  • Resilience
  • Elasticity
  • Message-driven communication

More at: https://www.reactivemanifesto.org

💬 Messages vs Commands vs Events Command

  1. Has intent
  2. 1-to-1 from producer → consumer
  3. Request-based

Example: CreateCustomer

Event

  • No intent — purely a notification
  • 1-to-many subscribers
  • Fact-based

Example: CustomerCreated

☁️ Azure Messaging Services Overview

Azure provides a broad messaging ecosystem including:

  • Service Bus
  • Event Hubs
  • Event Grid
  • Storage Queues

Serverless and Integration Services

🔷 What Is Azure Event Grid?

Azure Event Grid is a cloud-native, fully managed event routing service for building event-driven and microservice-oriented systems without heavy plumbing.

🎯 What Is Event Grid For?

  • Serverless apps
  • Ops automation
  • Third-party integrations

Azure Integration Services

🔄 Event Grid vs Service Bus vs Event Hub

A quick framing:

  • Event Grid → reactive notifications (push model, lightweight)
  • Service Bus → commands, workflow coordination, reliable messaging
  • Event Hub → large event ingestion, telemetry, streaming

📣 Why a Push Model?

Event Grid pushes events to subscribers as they occur, supporting system-wide reactivity.

Example system events:

  • Microsoft.Storage.BlobCreated
  • Microsoft.ServiceBus.ActiveMessagesAvailableWithNoListeners

🧩 Event Schemas

  • Event Grid Native Schema
  • Standard structure used by Azure Event Grid.
  • CloudEvents Schema

An industry-standard, cloud-agnostic event schema.

Resources:

https://cloudevents.io

CNCF Serverless Working Group

GitHub: https://github.com/cloudevents/spec

.NET SDK: https://github.com/aliencube/CloudEvents.NET

⚙️ Triggers

Event Grid can trigger:

  • Azure Functions
  • Logic Apps
  • Automation workflows
  • Webhooks
  • Custom subscribers

🔐 Security

Event Grid supports:

  • Managed identities
  • Key authentication
  • IP filtering
  • Private endpoints
  • Event domain-level access controls

📊 Event Grid – Daily Metrics

  • Native monitoring includes:
  • Delivery attempts
  • Latency
  • Subscriber response codes
  • Dead-letter events

🗂️ Event Domains

Allows multi-tenant event routing at scale, ideal for large distributed platforms.

Excluded 6 demos done on day :(

🧪 Demo Highlights Demo 1

Ride the grid: event publishing and subscriptions.

Demo 2

Live event monitoring 🔗 https://eventsmonitoring2019.azurewebsites.net/

Demo 3

_Microsoft Flow integration. _ Demo 4

Dumb insurance claim management flow

Example pattern:

_Inbound API request → publish event _ Event subscriber → execute command

Event publisher → emit result event

Multiple subscribers react

🏗️ Claim Entity Event Flow Example

For each Claim:

Claim has a Status

Business process flows trigger on status changes

Status updates broadcast events

Microservices react and write back updates

BPF rules trigger again from field updates

Reactive loops power distributed workflows.

Thanks & remember ‘#PushDontPull’

🙌 Images