@gm Sure they can. For example: this is a simple use case for nifi to tail a log file and send the results to a Kafka topic.
There are many other ways to do this without nifi too.
If this answer resolves your issue or allows you to move forward, please choose to ACCEPT this solution and close this topic. If you have further dialogue on this topic please comment here or feel free to private message me. If you have new questions related to your Use Case please create separate topic and feel free to tag me in your post.