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Chaos Duplicate Messages

This interceptor injects duplicate records on produce requests.

This demo will run you through some of these use cases step-by-step.

View the full demo in realtime​

You can either follow all the steps manually, or watch the recording

Review the docker compose environment​

As can be seen from docker-compose.yaml the demo environment consists of the following services:

  • gateway1
  • gateway2
  • kafka-client
  • kafka1
  • kafka2
  • kafka3
  • schema-registry
  • zookeeper
cat docker-compose.yaml

Starting the docker environment​

Start all your docker processes, wait for them to be up and ready, then run in background

  • --wait: Wait for services to be running|healthy. Implies detached mode.
  • --detach: Detached mode: Run containers in the background
docker compose up --detach --wait

Creating virtual cluster teamA​

Creating virtual cluster teamA on gateway gateway1 and reviewing the configuration file to access it

# Generate virtual cluster teamA with service account sa
token=$(curl \
    --request POST "http://localhost:8888/admin/vclusters/v1/vcluster/teamA/username/sa" \
    --header 'Content-Type: application/json' \
    --user 'admin:conduktor' \
    --silent \
    --data-raw '{"lifeTimeSeconds": 7776000}' | jq -r ".token")

# Create access file
echo  """
bootstrap.servers=localhost:6969
security.protocol=SASL_PLAINTEXT
sasl.mechanism=PLAIN
sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required username='sa' password='$token';
""" > teamA-sa.properties

# Review file
cat teamA-sa.properties

Creating topic topic-duplicate on teamA​

Creating on teamA:

  • Topic topic-duplicate with partitions:1 and replication-factor:1
kafka-topics \
    --bootstrap-server localhost:6969 \
    --command-config teamA-sa.properties \
    --replication-factor 1 \
    --partitions 1 \
    --create --if-not-exists \
    --topic topic-duplicate

Adding interceptor duplicate-messages​

Let's create the interceptor against the virtual cluster teamA, instructing Conduktor Gateway to inject duplicate records on produce requests.

cat step-07-duplicate-messages.json | jq

curl \
    --request POST "http://localhost:8888/admin/interceptors/v1/vcluster/teamA/interceptor/duplicate-messages" \
    --header 'Content-Type: application/json' \
    --user 'admin:conduktor' \
    --silent \
    --data @step-07-duplicate-messages.json | jq

Listing interceptors for teamA​

Listing interceptors on gateway1 for virtual cluster teamA

curl \
    --request GET 'http://localhost:8888/admin/interceptors/v1/vcluster/teamA' \
    --header 'Content-Type: application/json' \
    --user 'admin:conduktor' \
    --silent | jq

Send message to our created topic​

Producing 1 message in topic-duplicate in cluster teamA

Sending 1 event

{
  "message" : "hello world"
}

with

echo '{"message": "hello world"}' | \
    kafka-console-producer \
        --bootstrap-server localhost:6969 \
        --producer.config teamA-sa.properties \
        --topic topic-duplicate

Let's consume the message, and confirm message was duplicated​

Let's consume the message, and confirm message was duplicated in cluster teamA

kafka-console-consumer \
    --bootstrap-server localhost:6969 \
    --consumer.config teamA-sa.properties \
    --topic topic-duplicate \
    --from-beginning \
    --timeout-ms 10000 | jq

returns 2 events

{
  "message" : "hello world"
}
{
  "message" : "hello world"
}

Tearing down the docker environment​

Remove all your docker processes and associated volumes

  • --volumes: Remove named volumes declared in the "volumes" section of the Compose file and anonymous volumes attached to containers.
docker compose down --volumes

Conclusion

Yes, Chaos Duplicate Messages is simple as it!