question Expression language for Kafka Broker of PublishKafka_0_10 processor in Archives of Support Questions (Read Only)

Expression language for Kafka Broker of PublishKafka_0_10 processor

sy_robert — Tue, 21 Mar 2017 18:24:23 GMT

Hello,

I use a HandleHttpRequest to get a POST request with 2 parameters (kafkaHost and kafkaPort)

I can see my param in the attribute of the data (http.param.kafkaHost and http.param.kafkaPort)

I want to use them in a PublishKafka_0_10 to define kafka Brokers propertie (support expression language)

like this : Kafka Brokers = ${http.param.kafkaHost}:${http.param.kafkaPort}

It's doesn't works, my attributes aren't use (log file : bootstrap.servers = [:])

There is a solution ?

Re: Expression language for Kafka Broker of PublishKafka_0_10 processor

MattWho — Tue, 21 Mar 2017 19:58:34 GMT

@Sylvain Robert

The PublishKafka processor establishes a connection to the brokers before it even looks at the attributes of a FlowFile. This way it does not need to establish a new connection for every single FlowFile. While the broker property does not support FlowFile attributes, it should support resolving Expression Language statements that pull values from environment variables or the NiFi variable registry (File on disk with key value pairs).

Thank you,

Matt

Re: Expression language for Kafka Broker of PublishKafka_0_10 processor

sy_robert — Tue, 21 Mar 2017 20:08:22 GMT

Thanks Matt, i will find another way so.

Re: Expression language for Kafka Broker of PublishKafka_0_10 processor

sivat — Sun, 04 Apr 2021 01:36:46 GMT

Hello @sy_robert,

were you able to resolve this on how to dynamically assign brokers list from a flowfile attributes?

Re: Expression language for Kafka Broker of PublishKafka_0_10 processor

VidyaSargur — Mon, 05 Apr 2021 05:50:32 GMT

@sivat as this is an older post, you would have a better chance of receiving a resolution by starting a new thread. This will also be an opportunity to provide details specific to your environment that could aid others in assisting you with a more accurate answer to your question. You can link this thread as a reference in your new post.

Re: Expression language for Kafka Broker of PublishKafka_0_10 processor

sivat — Mon, 05 Apr 2021 13:18:56 GMT

@VidyaSargur thank you for the recommendation.

I already started a new thread https://community.cloudera.com/t5/Support-Questions/trying-to-assign-JMS-Broker-URI-property-value-at-runtime/td-p/313989 which is almost the same question as this thread.

Just wanted to check if @sy_robert found any workaround over this.