Quarkus Flow Applications

Learn how to structure and configure Quarkus Flow applications to work with Data Index.

Overview

To integrate with Data Index, your Quarkus Flow application needs:

Structured logging enabled - Emit JSON events to stdout
Kubernetes deployment - Run in Kubernetes where Vector can collect logs
Proper configuration - Property files for different environments

Application Structure

A typical Quarkus Flow application has this structure:

my-workflow-app/
├── pom.xml
├── src/
│   ├── main/
│   │   ├── java/
│   │   │   └── com/example/
│   │   │       ├── workflows/
│   │   │       │   └── MyWorkflow.java      # Java DSL workflows
│   │   │       └── resources/
│   │   │           └── WorkflowResource.java # JAX-RS endpoints
│   │   └── resources/
│   │       ├── application.properties         # Common config
│   │       ├── application-kind.properties    # KIND local dev
│   │       ├── application-prod.properties    # Production runtime
│   │       └── workflows/                     # YAML workflows (optional)
│   └── test/
│       └── java/
│           └── com/example/
│               └── WorkflowTest.java

Required Dependencies

Add to your pom.xml:

<dependencies>
    <!-- Quarkus Flow runtime -->
    <dependency>
        <groupId>io.quarkiverse.flow</groupId>
        <artifactId>quarkus-flow</artifactId>
    </dependency>

    <!-- REST API -->
    <dependency>
        <groupId>io.quarkus</groupId>
        <artifactId>quarkus-rest-jackson</artifactId>
    </dependency>

    <!-- Health checks -->
    <dependency>
        <groupId>io.quarkus</groupId>
        <artifactId>quarkus-smallrye-health</artifactId>
    </dependency>
</dependencies>

Structured Logging Configuration

Data Index requires structured logging to capture workflow events. Add to application.properties:

# Application name
quarkus.application.name=my-workflow-app

# Structured logging (REQUIRED for Data Index)
quarkus.flow.structured-logging.enabled=true
quarkus.flow.structured-logging.events=workflow.*
quarkus.flow.structured-logging.include-workflow-payloads=true
quarkus.flow.structured-logging.include-task-payloads=false
quarkus.flow.structured-logging.timestamp-format=epoch-seconds
quarkus.flow.structured-logging.log-level=INFO

# Console handler for JSON events
quarkus.log.handler.console."FLOW_EVENTS_CONSOLE".enabled=true
quarkus.log.handler.console."FLOW_EVENTS_CONSOLE".format=%s%n

# Route structured logging to console
quarkus.log.category."io.quarkiverse.flow.structuredlogging".handlers=FLOW_EVENTS_CONSOLE
quarkus.log.category."io.quarkiverse.flow.structuredlogging".use-parent-handlers=false
quarkus.log.category."io.quarkiverse.flow.structuredlogging".level=INFO

See the Quarkus Flow Structured Logging documentation for detailed configuration options.

Why Epoch Seconds?

The MODE 1 PostgreSQL triggers parse the event’s timestamp/startTime/endTime fields with to_timestamp(… ::numeric), so they must be Unix epoch seconds. Using epoch-seconds ensures proper timestamp parsing.

JAX-RS Endpoints (Required)

Quarkus Flow does NOT provide default REST endpoints. You must create JAX-RS resources to trigger workflows:

package com.example.resources;

import com.example.workflows.MyWorkflow;
import io.smallrye.mutiny.Uni;
import jakarta.inject.Inject;
import jakarta.ws.rs.*;
import jakarta.ws.rs.core.MediaType;
import java.util.Map;

@Path("/workflows")
public class WorkflowResource {

    @Inject
    MyWorkflow myWorkflow;

    @POST
    @Path("/start")
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public Uni<Map<String, Object>> startWorkflow(Map<String, Object> input) {
        return myWorkflow.startInstance(input)
                .onItem().transform(result -> result.asMap().orElseThrow());
    }
}

Next Steps

Now that you understand the basics, choose your deployment target:

Local Development with KIND - Test locally
Production Deployment - Deploy to Kubernetes

Both guides cover:

Kubernetes deployment dependencies
Environment-specific property files
Build and deployment commands
Verification steps