Spring Cloud Data Flow DLQ Configuration not working

Question

I am trying to configure DLQ in Spring Cloud Data Flow. Here is the Stream defination and how I am deploying it

  stream create --definition ":someTestTopic > custom-transform
     --spring.cloud.stream.bindings.input.consumer.headerMode=raw | log --spring.cloud.stream.bindings.input.consumer.headerMode=raw" --name ticktran


    stream deploy ticktran --properties
  "apps.log.spring.cloud.stream.bindings.input.consumer.headerMode=raw,apps.custom-transform.spring.cloud.stream.bindings.input.consumer.headerMode=raw,app.custom-transform.spring.cloud.stream.bindings.output.destination=test-tran,app.log.spring.cloud.stream.bindings.input.destination=test-tran,app.custom-transform.spring.cloud.stream.kafka.bindings.test-tran.consumer.enableDlq=true"

In custom-transform - processor code, I have mentioned

if(out.contains("ERROR")) {
            throw new RuntimeException("Error ");
        }

That means if message contains ERROR then RunTimeException and I want to capture those messages in DLQ. But it seems when I am running the code I am not getting any Kafka DL Queue with name test-tran.

Do i need to set more properties to enable DLQ or I need to change something in code for proper use of DLQ.

Custom Transform Code

TransformationServiceApplication.java

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.hateoas.config.EnableEntityLinks;

@SpringBootApplication
@EnableEntityLinks
public class TransformationServiceApplication {

    public static void main(String[] args) {
        SpringApplication.run(TransformationServiceApplication.class, args);
    }
}

TransformationMessageEndPoint.java

@EnableBinding(Processor.class)
@MessageEndpoint
public class TransformationMessageEndpoint {

    private static final String NS = "http://openrisk.com/ingestion/";

    AtomicInteger index = new AtomicInteger(1);
    @ServiceActivator(inputChannel = Processor.INPUT, outputChannel = Processor.OUTPUT)
    public Object process(Message<?> message) {
        String out =  new String((byte[])message.getPayload());

        System.out.println("*****" + out);

        if(out.contains("ERROR")) {
            throw new RuntimeException("Error ");
        }

        return message;

    }
}

pom.xml

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.6.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-dataflow-server-local</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-stream-kafka</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-stream-binder-kafka -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream-binder-kafka</artifactId>
            <version>1.0.0.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-stream-test-support</artifactId>
            <version>1.0.0.BUILD-SNAPSHOT</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud.stream.module</groupId>
            <artifactId>spring-cloud-stream-modules-test-support</artifactId>
            <version>1.0.0.BUILD-SNAPSHOT</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.jena</groupId>
            <artifactId>jena-core</artifactId>
            <version>3.1.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.8.0</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

Adding Module

app register --name custom-transform --type processor --uri maven://com.openrisk.openmargin:TransformationService:0.0.1-SNAPSHOT

Adding Stream

stream create --definition ":someTesstTopic > custom-transform | log " --name ticktran

Deploy Stream

stream deploy ticktran --properties "app.log.spring.cloud.stream.bindings.input.consumer.headerMode=raw,app.custom-transform.spring.cloud.stream.bindings.input.consumer.headerMode=raw,app.custom-transform.spring.cloud.stream.kafka.bindings.input.consumer.enableDlq"

Answer 1

There were few issues with your stream definition.

• The deployment properties start with app.<app-name>., but you've apps.<app-name>. in few places.
• The destinations are automatically created in SCDF, so having to override the defaults wouldn't be recommended. You can, however, do this when you're running standalone spring-cloud-stream applications.
• Instead of using custom destinations, you can enable DLQ by interacting with default channels directly - see example below.

stream create --definition ":someTesssstTopic > transform | log " --name ticktran

stream deploy ticktran --properties "app.log.spring.cloud.stream.bindings.input.consumer.headerMode=raw,app.transform.spring.cloud.stream.bindings.input.consumer.headerMode=raw,app.transform.spring.cloud.stream.kafka.bindings.input.consumer.enableDlq"

• The destination test-tran is not in the acceptable format when it comes to referring in the app.transform.spring.cloud.stream.kafka.bindings.<channelName>.consumer.enableDlq property.
• Lastly, the error.<destination>.<group> topic is only created when there's an error.

We will add few DSL samples to the reference guide via: #885.

EDIT: I updated the stream definition to reflect the right deployment property prefix.

Answer 2

I changed the Data flow version to 1.1 M1 release with the below mention command to create and deploy properties and it working now

stream create --definition ":someTesstTopic > transform | log " --name ticktran


stream deploy ticktran --properties "app.log.spring.cloud.stream.bindings.input.consumer.headerMode=raw,app.transform.spring.cloud.stream.bindings.input.consumer.headerMode=raw,app.transform.spring.cloud.stream.kafka.bindings.input.consumer.enableDlq"

Thanks Sabby Anandan