{
  "type": "record",
  "name": "TestMessage",
  "namespace": "com.example.kafka",
  "doc": "A simple test message schema for Kafka with Avro",
  "fields": [
    {
      "name": "id",
      "type": "string",
      "doc": "Unique identifier for the message"
    },
    {
      "name": "message",
      "type": "string",
      "doc": "The main message content"
    },
    {
      "name": "timestamp",
      "type": "long",
      "doc": "Unix timestamp when the message was created"
    },
    {
      "name": "metadata",
      "type": ["null", "string"],
      "default": null,
      "doc": "Optional metadata field"
    }
  ]
}