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Chaos Simulate 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
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 topic topic-duplicate on gateway1​

Creating on gateway1:

  • Topic topic-duplicate with partitions:1 and replication-factor:1
kafka-topics \
    --bootstrap-server localhost:6969 \
    --replication-factor 1 \
    --partitions 1 \
    --create --if-not-exists \
    --topic topic-duplicate

Adding interceptor duplicate-messages​

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

step-06-duplicate-messages-interceptor.json:

{
  "kind" : "Interceptor",
  "apiVersion" : "gateway/v2",
  "metadata" : {
    "name" : "duplicate-messages"
  },
  "spec" : {
    "comment" : "Adding interceptor: duplicate-messages",
    "pluginClass" : "io.conduktor.gateway.interceptor.chaos.DuplicateMessagesPlugin",
    "priority" : 100,
    "config" : {
      "rateInPercent" : 100,
      "topic" : "topic-duplicate",
      "target" : "PRODUCE"
    }
  }
}
curl \
    --silent \
    --request PUT "http://localhost:8888/gateway/v2/interceptor" \
    --header "Content-Type: application/json" \
    --user "admin:conduktor" \
    --data @step-06-duplicate-messages-interceptor.json | jq

Listing interceptors​

Listing interceptors on gateway1

curl \
    --silent \
    --request GET "http://localhost:8888/gateway/v2/interceptor" \
    --user "admin:conduktor" | jq

Send message to our created topic​

Producing 1 message in topic-duplicate in cluster gateway1

Sending 1 event

{
  "message" : "hello world"
}
echo '{"message": "hello world"}' | \
    kafka-console-producer \
        --bootstrap-server localhost:6969 \
        --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 gateway1

kafka-console-consumer \
    --bootstrap-server localhost:6969 \
    --topic topic-duplicate \
    --from-beginning \
    --max-messages 3 \
    --timeout-ms 3000 | 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 Simulate Duplicate Messages is simple as it!