microservices and multiple databases

Question

i have written MicroServices like for auth, location, etc. All of microservices have different database, with for eg location is there in all my databases for these services.When in any of my project i need a location of user, it first looks in cache, if not found it hits the database. So far so good.Now when location is changed in any of my different databases, i need to update it in other databases as well as update my cache.

currently i made a model (called subscription) with url as its field, whenever a location is changed in any database, an object is created of this subscription. A periodic task is running which checks for subscription model, when it finds such objects it hits api of other services and updates location and updates the cache. I am wondering if there is any better way to do this?

Answer 1

I am wondering if there is any better way to do this?

"better" is entirely subjective. if it meets your needs, it's fine.

something to consider, though: don't store the same information in more than one place.

if you need an address, look it up from the service that provides address, every time.

this may be a performance hit, but it eliminates the problem of replicating the data everywhere.

another option would be a more proactive approach, as suggested in comments.

instead of creating a task list for changes, and doing that periodically, send a message across rabbitmq immediately when the change happens. let every service that needs to know, get a copy of the message and update it's own cache of info.

just remember, though. every time you have more than one copy of the information, you reduce the "correctness" of the system, as a whole. it will always be possible for the information found in one of your apps to be out of date, because it did not get an update from the official source.