What the point of RAP on S/4 HANA on-premise 1909

[Rodrigo-Giner]

Hi, I'm really struggling trying to understand this. The RAP can be used on ABAP Enviroment (Cloud) and OnPremise S/4 HANA 1909.

I understand the technicall concept of using RAP in the ABAP Enviroment on the cloud, even though so far IMHO it seems plain stupid. Unless there is a way to deal with all the limitation that has so far. I mean why I would choose using ABAP to work on the cloud? it's like look "ABAP is not dead", well if we have to do from scratch %99.99 of the custom development a lot of customers could say this is a good moment to just get rid of ABAP once for all and don't tell me that the advantage is to leverage the experience and knowledge when 90% of the ABAP developers comunity doesn't even know what SOLID is. But this is another subject.

Back to my original question why I would want to use RAP on premise ? I mean besides the fact that you can actually trully migrate your code to the cloud in the future? Is there another PRO that I'm failing to see ?

[maheshpalavalli]

There is no simple approach in SAP to create a complex webservice with all CRUD operations supported rhat can be easily understood by a webapp(fiori app). So SAP gave ODATA creation support via segw. Still it's not a simple approach, a lot of code has to be written here..

So they integrated CDS views and BOPF via ABAP programming model for fiori.. this made the creation of fiori apps with templates a lot easier as it gives annotations file via CDs annotations.

Now the next evolved form is RAP, this makes development even a lot easier and supports fully typed programming unlike the above bopf part and with many other features.

So a simple answer to ur question is rap is needed as a framework to create complex webservices in a simpler way that will be easily understood by webapps for e.g., fiori apps that uses the annotations that were mentioned in the rap model which will be used in fiori template based apps(no code and complex ui output )

So I am not sure how rap helps in the migration of the code, but above is what I believe is the reason. And there are many other advantages of RAP(eg. in integration scenarios). You can check them out in the documentation and various other blogs.

[Rodrigo-Giner]

Hi, thanks for your thoughts. but you are taking about RAP in general. What about on-premise ? that's my main question. Why I even would want doing RAP on my on-premise server. Is there any advantages ?

Regarding RAP. Is an evolution I give you that, but that doesn't mean that's a good one. Webdynpro was also an evolution and was awful, SAP Netweaver Portal was pretty much a big failure and sadly I think SAP Fiori is on the same track. All SCP is based on HTTP 1.1 Protocol and has major performace issue compared to others web frameworks. Besides if SAP Fiori and SAP Fiori Elements are the path to follow... why even bother on creating "UI5 Web Components"

Don't get me wrong. I trully want to be a "believer".... but so far I'm not convinced.

[maheshpalavalli]

Hi rodrigoariel.ginerdelavega,

No i was talking about on-prem only, we need odata services in on premise as well right? So there comes the RAP, although you might be seeing all the demos on abap environment(cloud), it is also for on premise(current in a lesser version). Advantages are the same as I mentioned in the original answer.

Yes I agree there are some issue, but ui5 is evolving a lot and is lot faster now compared to couple of years back, more than twice.. You can check about http2 request here

https://blogs.sap.com/2017/08/30/how-http2-feature-can-improve-your-fiorisapui5-solution-performance...

But don't worry about ui5 webcompnents, they ar e not going to replace ui5 or meant to replace ui5, UI5 is a framework to create web apps(mvc) but webcompnentss are supposed to provide UI only, not the framework that comes in UI5, SAP even have future plan to integrate UI5 wecomponents inside UI5, eg., instead of that HTML CSS content for those input boxes, we will have a wrapper input box control in ui5 that consumes ui5 webcompnent input control (this is just my guess). and Moreover, ui5 cannot be used in other sap systems, like successfactors.. where they can use these generic ui5 webcomponents and have a consistent look and feel across all systems.