I need to create a service to collect and consolidate events from other services, as far as found on internet ,the aggregator service helps to find out what's going on in the application flow, I have confusion here which need your help, aggregator microservice means if any input or output from a service should be sent to the aggregator service with time and date? But in clouds also we have such a service like application insights, does not it do the same thing? Even if we store every event it gona be a huge data in the db,is it really a best solution?
So Answering your first question,
Aggregator microservice means if any input or output from a service should be sent to the aggregator service with time and date? Not Really, Aggregator Microservice is a pattern, which is basically another service that receives requests, subsequently makes requests to multiple different services and combines the results and responds to the initiating request.
So I guess you're looking for some Log aggregators, which are software functions that consolidate log data from throughout the IT infrastructure into a single centralized platform where it can be reviewed and analyzed.
But in clouds also we have such a service like application insights, does not it do the same thing? Yes, you can say that it's a similar service.
Even if we store every event it gona be a huge data in the db,is it really a best solution? Leave this with your Log aggregator tool, it will have a proper mechanism to keep your data. Mostly they will keep the data in a compact way and properly indexed too.