KAFKA-3945: Change the type of 'acks' config in console producer to String

[vahidhashemian]

The acks config that is provided to console producer with request-required-acks comes with all, -1, 0, 1 as valid options (all and -1 being interchangeable). Currently, the console producer expects an integer for this input and that makes all to become an invalid input. This PR fixes this issue by changing the input type to String.

[omkreddy]

LGTM

[granthenke]

LGTM

[ijuma]

We no longer need to call toString in config.requestRequiredAcks.toString (there are two instances of this).

[vahidhashemian]

That's right. Thanks for catching those. Will update shortly.

[ijuma]

The PR description seems a bit misleading. We talk of validation of valid input, but it seems to me that we don't do any validation apart from setting the type of the parameter (previously Integer and now String). Is that right? Have we checked that the user gets an appropriate and friendly error if they pass an invalid parameter with the new code?

[vahidhashemian]

That's right, what I meant by validation was verifying that the input type is a string and not an integer. I'll try to make this more clear in the description.

With the new code, if I provide any input other than those accepted I get this error:

org.apache.kafka.common.config.ConfigException: Invalid value ... for configuration acks: String must be one of: all, -1, 0, 1
    at org.apache.kafka.common.config.ConfigDef$ValidString.ensureValid(ConfigDef.java:827)
    at org.apache.kafka.common.config.ConfigDef.parse(ConfigDef.java:427)
    at org.apache.kafka.common.config.AbstractConfig.<init>(AbstractConfig.java:56)
    at org.apache.kafka.common.config.AbstractConfig.<init>(AbstractConfig.java:63)
    at org.apache.kafka.clients.producer.ProducerConfig.<init>(ProducerConfig.java:337)
    at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:188)
    at kafka.producer.NewShinyProducer.<init>(BaseProducer.scala:40)
    at kafka.tools.ConsoleProducer$.main(ConsoleProducer.scala:45)
    at kafka.tools.ConsoleProducer.main(ConsoleProducer.scala)

[vahidhashemian]

@ijuma The PR was updated. I hope it addresses your concerns. Thanks.

[vahidhashemian]

@ijuma Friendly ping :)

[ijuma]

It would probably be a bit nicer if we didn't print the stacktrace for such cases, but that applies to other parameters too, so perhaps something for another PR. LGTM.

[ijuma]

Merged to trunk.