Extract producer configuration with empty properties

[ices1231]

I have a problem with Producer configuration with optional empty properties. I want to configure security, but disable it in dev profile.

Background

application.yml

mp:
  messaging:
    outgoing:
      test-name:
        connector: smallrye-kafka
        bootstrap:
          servers: localhost:9092
        sasl:
          jaas:
            config: org.apache.kafka.common.security.scram.ScramLoginModule required username=admin password=admin;
          mechanism: SCRAM-SHA-512
        security:
          protocol: SASL_PLAINTEXT
        key:
          serializer: org.apache.kafka.common.serialization.StringSerializer
        value:
          serializer: org.apache.kafka.common.serialization.StringSerializer


"%dev":
   mp:
    messaging:
      outgoing:
      	test-name:
          sasl:
            jaas:
              config: ""
            mechanism: ""
          security:
            protocol: PLAINTEXT

According to eclipse/microprofile-config#446 all is correct I got

Caused by: java.util.NoSuchElementException: Cannot find attribute sasl.mechanism for channel test-name. Has been tried: mp.messaging.outgoing.test-name.sasl.mechanism and mp.messaging.connector.smallrye-kafka.sa
sl.mechanism
at io.smallrye.reactive.messaging.impl.ConnectorConfig.getValue(ConnectorConfig.java:72)
at io.smallrye.reactive.messaging.kafka.impl.JsonHelper.asJsonObject(JsonHelper.java:14)
at io.smallrye.reactive.messaging.kafka.impl.KafkaSink.extractProducerConfiguration(KafkaSink.java:131)
at io.smallrye.reactive.messaging.kafka.impl.KafkaSink.(KafkaSink.java:40)
at io.smallrye.reactive.messaging.kafka.KafkaConnector.getSubscriberBuilder(KafkaConnector.java:86)

Alternative

It is hard to make security properties optional.
Can you change JsonHelper.java, as you did it here default-configuration

config.getValue()  -> config.getOptionalValue()

Thank you in advance

[cescoffier]

That sounds reasonable.

Can you open a PR?

[cescoffier]

Closed #558