4 ms·

To me microservices work when you split out things that the core app doesn't always need. So "promocodes" becomes its own microservice because not all purchase

To me microservices work when you split out things that the core app doesn't always need. So "promocodes" becomes its own microservice because not all purchases need a promo code. And now the main app isn't cluttered with promo code admin logic and UI.

joshmarlow 10y ago
Another example that I'm fond of: Central authentication service that authenticates on user login and passes back and API token to be used to access other services. With something like a JWT you don't need to check the User database for every API call.
- vidarh 10y ago
  Exactly. This is how I see microservices as most valuable: When communication is mediated by the client. And tokens can be great for that in all kinds of circumstances to allow the client to mediate communications even when trust is required.
unscaled 10y ago
Exactly. I've seen many monoliths which were bloated with pieces of functionality developed for specific needs that other parts of the company had. So your shopping cart API would get promocodes, and coupons, and express delivery, donation offers, credit card selection, support for legacy authentication and so on. And then you had to convert this behemoth from Java 5 or PHP 5 into something modern, but it ended up being too messy and you're stuck. Yes, implementing all these features as microservice won't simplify the architecture, but you'll at least be able to easily migrate upgrade, remove, replace or scale up pieces of it.
- js8 10y ago
  > you'll at least be able to easily migrate upgrade, remove, replace or scale up pieces of it IMHO, you're painting a very rosy picture here. There is a big assumption that you will want to preserve existing interfaces (REST APIs?) between those microservices. In reality, they probably will be bloated and obsolete just like everything else you have. And being forced to update "microservice" at a time rather than as a whole, the whole process will actually become more complicated.

joshmarlow 10y ago

Another example that I'm fond of: Central authentication service that authenticates on user login and passes back and API token to be used to access other services. With something like a JWT you don't need to check the User database for every API call.

vidarh 10y ago
Exactly. This is how I see microservices as most valuable: When communication is mediated by the client. And tokens can be great for that in all kinds of circumstances to allow the client to mediate communications even when trust is required.

unscaled 10y ago

Exactly. I've seen many monoliths which were bloated with pieces of functionality developed for specific needs that other parts of the company had. So your shopping cart API would get promocodes, and coupons, and express delivery, donation offers, credit card selection, support for legacy authentication and so on. And then you had to convert this behemoth from Java 5 or PHP 5 into something modern, but it ended up being too messy and you're stuck. Yes, implementing all these features as microservice won't simplify the architecture, but you'll at least be able to easily migrate upgrade, remove, replace or scale up pieces of it.

js8 10y ago
> you'll at least be able to easily migrate upgrade, remove, replace or scale up pieces of it IMHO, you're painting a very rosy picture here. There is a big assumption that you will want to preserve existing interfaces (REST APIs?) between those microservices. In reality, they probably will be bloated and obsolete just like everything else you have. And being forced to update "microservice" at a time rather than as a whole, the whole process will actually become more complicated.