I am stuck in a problem while using Kafka in a microservice architecture . I am not able to understand how a microservice handling HTTP requests will be able to send a response to the user. I want to take data from HTTP and then publish it to topic named A then another validator service will validate it and publish it on another topic named B. I want to send processed data to HTTP response from subscribed data from topic B.

CodePudding user response：

In my experience, one option is to respond immediately with 201 accepted, or embed a blocking validator library into your API, and properly return a 400 Bad Request.

Then future GET calls are required to read eventually consistent data that might come back from any consumer. E.g. the consumer process is Kafka Connector that writes to some database, or is a Kafka Streams/KSQL table and the API queries and returns data from that. Your original client may need to make periodic HTTP events until that data is available.