Kafka messages with duplicate header keys prevent the message browser from displaying in the UI

[gmcrobert]

Issue Description

When a producer for a topic creates message headers and more than 1 header has the same key, the messages cannot be displayed in the messages panel for the topic in the Event Streams UI.

The messages panel will display an error page but no notifications will be issued. To diagnose the problem, you need to inspect the network responses to requests in the browser when the Messages tab is opened for a selected topic. The request to look for is a POST https:///api/admin/gql/queries. The status code in the response for that request will be set to 200 ok but the response payload will contain an error similar to the following:

{"errors":[{"message":"Exception while fetching data (/topicData/partitions[0]/records) : Duplicate key dup-key (attempted merging values [B@5cf67132 and [B@fd8fe03a)","locations":[{"line":6,"column":7}],"path":["topicData","partitions",0,"records"],"extensions":{"classification":"DataFetchingException"}}],"data":{"topicData":{"partitions":[{"id":0,"latestOffset":5,"records":null,"__typename":"Partition"}],"__typename":"Topic"}}}

Environment

• IBM Event Streams Version: 10.1