Traditional Liferay implementations often rely on synchronous REST calls, creating tightly coupled systems that are difficult to scale and maintain. This session explores how to transform Liferay into an event-driven platform using Kafka, message queues, webhooks, and asynchronous processing. Learn how to build scalable, resilient, and loosely coupled enterprise solutions that seamlessly integrate with external systems such as SAP, Salesforce, payment gateways, and custom microservices.

Problem Statement

Most Liferay projects look like:

User
  ↓
Liferay
  ↓
REST API
  ↓
SAP

Issues:

Slow response times
SAP downtime affects portal
High coupling
Poor scalability
Failed transactions are difficult to recover

Event-Driven Solution

User
  ↓
Liferay
  ↓
Kafka Topic
  ↓
Consumers
 ├── SAP
 ├── CRM
 ├── Notification Service
 └── Analytics Service

Benefits:

Loose coupling
Better scalability
Fault tolerance
Retry mechanisms
Real-time integrations

Kafka Integration with Liferay

Use Case

Citizen submits GST application.

Instead of:

callSAP();
callCRM();
sendEmail();

Publish event:

ApplicationSubmittedEvent

Producer from Liferay

ProducerRecord<String, String> record =
    new ProducerRecord<>(
        "citizen-applications",
        applicationJson);

producer.send(record);

Kafka Topics

citizen-applications

user-registration

payment-completed

document-uploaded

workflow-approved

Message Queues

Example: User uploads document.

Without Queue:

Upload
 ↓
Virus Scan
 ↓
OCR
 ↓
SAP Update
 ↓
Email

Response time:

20 seconds

With Queue:

Upload
 ↓
Queue
 ↓
Success Response

Background workers process:

OCR
SAP Update
Notifications

Response:

< 1 second

Async Processing in Liferay

Real Scenario

Generating reports for 500,000 records.

Bad approach:

MVCActionCommand
   ↓
Generate Report
   ↓
Return Response

Browser times out.

Better Approach

MVCActionCommand
   ↓
Publish Event
   ↓
Return Job ID

Background worker:

Generate PDF
Store Document
Notify User

User gets notification when complete.

Webhooks

Webhooks allow Liferay to notify external systems.

Example:

Workflow Approved

Trigger:

POST /external-api

Payload:

{
  "applicationId":"12345",
  "status":"APPROVED"
}

Use cases:

Salesforce updates
SAP integration
CRM synchronization
Payment notifications

Liferay Objects + Events

Many developers overlook this.

Objects can trigger:

Create
Update
Delete

events.

Example:

Citizen Object

Citizen Created

Automatically:

Webhook
Kafka Event
Notification
Workflow

No custom portlet required.

External System Communication

Common Enterprise Landscape

Liferay
  │
  ├── SAP
  ├── Salesforce
  ├── ServiceNow
  ├── Payment Gateway
  ├── ECM
  └── Government Systems

Instead of direct integrations:

Liferay
  ↓
Event Bus
  ↓
Microservices

Each system subscribes independently.

Building Event-Driven Enterprise Architectures with Liferay DXP, Kafka, and Microservices