When creating REST APIs should we always create microservices or avoid it in some cases?

When creating a REST API, it is advantageous to create Microservices instead of a monolithic application of REST APIs, as it gives separately deployable units and reduces dependency and coupling. Are there any cases where one should avoid creating Microservices ?
thanks

There's not really a direct correlation between the two--in my mind, they are orthogonal decisions. You can have a REST API that is backed by microservices or you can have a monolith behind it.  That's kind of like asking if you should wear a red shirt of a blue shirt if you're going to call a plumber.

Thanks

Junilu Lacar wrote:You can have a REST API that is backed by microservices or you can have a monolith behind it.

Any reason why we should not break that Mololythic application and break that into microservices as well?

Besides the fact that many organizations can't even get their sh*t together around a monolithic app, much less manage the complexities of microservices? Moving to microservices is not a straightforward process, especially if the monolith is like most monoliths out there: a tangled mess of dependencies that are difficult to separate.

You need good separation and an understanding of where your seams are in your monolith. You need a disciplined engineering corps that knows how to automate things and set up pipelines, etc. I could go on and on.

Thanks.

Junilu Lacar wrote:Besides the fact that many organizations can't even get their sh*t together around a monolithic app.

That sounds like for an existing application. Converting an existing monolythic application into Microservices may not be easy but what about the case for new application. If new application needs to be created for REST APIs, then should those always be microservices or here also monolythic may be preferred sometimes?

much less manage the complexities of microservices

I understand for an existing application. But do you mean for new applications as well? If so what kind of complexities?

Monica Shiralkar wrote:When creating a REST API, it is advantageous to create Microservices instead of a monolithic application of REST APIs, as it gives separately deployable units and reduces dependency and coupling. Are there any cases where one should avoid creating Microservices ?

I don't see how your arguments have anything to do with the API that a service/application might use.

Did you read somewhere that RESTful APIs are intended for microservice architectures?

Ron McLeod wrote:

Did you read somewhere that RESTful APIs are intended for microservice architectures?

Microservices are not limited to Web Services but one of the examples can be that multiple REST APIs with single purpose and independently deployable units which do not have dependency on each other instead of having a monolithic application where if one thing goes down it may affect the other as well.

Monica Shiralkar wrote:Microservices are not limited to Web Services but one of the examples can be that multiple REST APIs with single purpose and independently deployable units which do not have dependency on each other instead of having a monolithic application where if one thing goes down it may affect the other as well.

But wouldn't that same reasoning apply to applications or service providers which use non-RESTful APIs as well?

I don't feel the type of network API plays a significant part in the decision making for monolithic vs. microservice architecture.

Do you mean SOAP web services? Yes, it would.