[Bug] Duplicated content type in header when use kafka-http-connector

[chenjr0719]

Hi there, I found an issue in kafka-http-connector.

keda-connectors/kafka-http-connector/main.go

Lines 215 to 226 in da09425

	headers := http.Header{
	"KEDA-Topic": {conn.connectorData.Topic},
	"KEDA-Response-Topic": {conn.connectorData.ResponseTopic},
	"KEDA-Error-Topic": {conn.connectorData.ErrorTopic},
	"Content-Type": {conn.connectorData.ContentType},
	"KEDA-Source-Name": {conn.connectorData.SourceName},
	}
	// Set the headers came from Kafka record
	for _, h := range message.Headers {
	headers.Add(string(h.Key), string(h.Value))
	}

If the message header also specifies the same keys (ex: content-type), when it sends the request to the function might be broken because of the duplicate key.

I would like to know, is it possible to check the message header first, and if it doesn't contain the same key, we use the default value here?

[blackfly19]

Hi @chenjr0719. Can you please provide the steps to reproduce the issue?

[soharab-ic]

@chenjr0719 http.Header is of type map[string][]string. It can have a slice of values for every key. The Add method does not overwrite existing values, it appends new values to the slice associated with the key.