Standard SQS queues guarantee that a message is delivered at least once and duplicates can be introduced into the queue. So we need to handle the scenario where in we receive same message multiple times.
I came across a scenario where I cannot make my application idempotent because of my dependency on third party application. So I need to make sure before processing any message that its not a already processed.
I have read through basic of apache camel(https://camel.apache.org/components/4.0.x/aws2-sqs-component.html#_send_batch_message_and_message_deduplication_strategy) I but I am still not sure how apache camel internally can help achieve deduplication of SQS messages in multi instance environment.
To summarise my question :- I understand there could be repositories where camel can store message ids but what i really would like to know is how multiple instances of application communicate with each other. It will be required as per my understanding as duplicate message can be received by different instances of one application.