Technology Blogs by SAP
Learn how to extend and personalize SAP applications. Follow the SAP technology blog for insights into SAP BTP, ABAP, SAP Analytics Cloud, SAP HANA, and more.
cancel
Showing results for 
Search instead for 
Did you mean: 
qmacro
Developer Advocate
Developer Advocate
In this post you'll find a transcript of an interview between me and Rui Nogueira on the new Application Programming Model for SAP Cloud Platform. There's also a link to the audio version, available via Coffee Corner Radio.

Last week I was in Walldorf, and I managed to catch up with an old friend rui.nogueira where we chatted about the new Application Programming Model for SAP Cloud Platform (gosh, we're going to have to find a short way of saying that at some stage soon!). This new Application Programming model was introduced by daniel.hutzel and there's also a decent amount of information about it in the online SAP Help here: SAP Cloud Platform - Business Applications.

I turned the chat into an interview that we could share with you. I transcribed it, and the transcription is below. I've also made the audio available, in the form of a podcast episode on uxkjaer and Former Member's Coffee Corner Radio podcast - the episode is here:

Pod bite 5 - DJ Adams - interview with Rui Nogueira

I've done my best to find a balance between the "off the cuff" chat style, and a flow that is easy to read in transcribed form. Share & enjoy!

By the way, if you're interested in reading more about the concept of programming models, and how this model fits in, you might want to read this Monday morning thoughts post: "Monday morning thoughts: programming models".

 

Transcription of interview

Date: 21 June 2018
Location: WDF03, SAP Walldorf
With: Rui Nogueira

 

DJ: So I'm here today with Rui, hello Rui!

Rui: Hello DJ!

DJ: And what we're going to do is just talk a little bit about something that I chatted with Rui about at Sapphire, just to find out a little bit more about it. We're just going to do it off the cuff ...

Rui: Yes, we're just coming out of the coffee corner

DJ: We're just coming out of the coffee corner

Rui: at the mothership!

DJ: We *are* at the mothership! In building 03, I've just had a delicious lunch downstairs, including a very interesting asparagus & herb soup, as well [random conversation about the soup redacted]

DJ: OK, so what Rui and I chatted about in Sapphire, was the new programming model in town.

Rui: It's not just in town, it's even generally available

DJ: GA!

Rui: Yes! But I thought we'd just ... say it

DJ: Yes, it's generally available. And if I remember rightly, it's called the "Application Programming model for SAP Cloud Platform". Is that right, and what it is?

Rui: It is right indeed, and it's not a product, it's rather, as the name also proposes, also that strange long name, application programming *for* SAP Cloud Platform, to emphasise that this is not just a single product, right, it's actually leveraging some open source technologies as well as some SAP proprietary technologies. Mainly CDS, right, to help you create, quickly, enterprise grade applications with enterprise grade qualities on the cloud platform. So that's the main goal of this programming model.

DJ: OK, cool, so CDS - Core Data Services, right?

Rui: Exactly

DJ: So a lot of the listeners are going to be at least familiar with that is in general, but what does CDS bring to this programming model, how is it used?

Rui: So first of all, what we wanted to achieve with the programming model is to not start from scratch with something new, but thinking: how can we actually leverage the knowledge which is out there already around HANA, around ABAP, and bring that to the cloud platform. And initially, CDS built to define data models, right, for databases

DJ: *annotated* data models!

Rui: annotated, yes, so that you can derive out of that hdbcds files for HANA, so that the schema is created and so on and so forth, and what we have added to that, additional annotations for creating the corresponding services, to also create UIs on top

DJ: So I know there's a tutorial, I saw the blog post from Daniel

Rui: Daniel Hutzel

DJ: Yes, exactly, and he pointed to the documentation in help.sap.com and there's a really nice tutorial which I've been through quite a few times  

Rui: The Bookstore example

DJ: Yes, the Bookstore example, and talking of the Bookstore example, one of the things that struck me was the way that the entities were defined - the Book entity, the Author entity, and so on. They reminded me - I'm not sure if it's coincidence - of River, RDE.

Rui: Oh, yes, long time ago!

DJ: Yes, I mean, even the way that they were whitespaced out, and formatted and so on, I thought this reminds me of something, and I couldn't figure out what it was. So yeah, it's nice to see that some really cool ideas from way back when - I thought they were pretty cool - have sort of found their way into something that's new, right?

Rui: Yes, and in addition, the other aspect, we also look into the application programming model that you can easily also add and combine other services, like business services, with it, so, again, via the model itself, right, to be able to, on the one hand side, create reusable business services, but also embed them into your application.

DJ: Yes, I mean I get ... cos that seems pretty critical, with the programming model itself, to be able to create net new applications (to use that phrase "net new") - that's great, but I think a lot of people, including me, will want to be able to build side-by-side extensions for S/4HANA, for example, that's what you're talking about, right?

Rui: Yes, exactly, and specifically for S/4HANA, there is also a connection to the S/4HANA SDK which works also pretty well, so both teams are working closely together to ensure that they can leverage each other, and in addition, what we have done, is also using the programming model to build here at SAP also applications. And also reusable services, so, really taking that technology before it was generally available, to test whether this really works to efficiently and effectively create enterprise grade apps or not and we found gaps last year, right, and we closed them, and I think we're now in a state where I feel pretty confident that the application programming model really helps you to create such applications. Is it perfect? Is maybe stuff missing? Most probably yes, but what is definitely also true is that we have been using this programming model now already last year, here with SAP, to create services, specifically around security and data privacy, and that worked out pretty well.

DJ: So you're basically drinking your own champagne before you actually give it to the public.

Rui: Yes, so, improving the champagne, right?

DJ: No wonder your eyes look like they do!

Rui: This is just sparkling water!

DJ: OK. This is audio only. Because this morning I was told I have "a face for radio".

Rui: Makes sense, kind of!

DJ: So, one thing that is on my mind and I think on other people's minds as well is that there do seem to be a lot of phrases, a lot of places where I'm seeing the phrase "programming model". There seem to be a number of programming models out there. Where does this fit in ... for example, there's the programming model for Fiori, and there's the RESTful ABAP programming model and so on, so where does this fit in?

Rui: I think what has been developed before is still there, right, and if people called it "programming model" it's definitely true. Specifically for the application programming model, as I said before, we are trying to create a combination between open source topics and SAP proprietary technology and the way that the programming model is built is that yes for sure we currently start with for example on the persistence side with HANA, on the server side with OData, on the UI side with SAPUI5 and Fiori, but the whole model allows us to go beyond that and also maybe create other assets, right - on the persistence side to maybe create assets for other databases ...

DJ: So create definitions for other targets?

Rui: Exactly. So of course we start with these technologies now with SAP products, but the model itself open

DJ: Sort of an abstraction layer, really, isn't it?

Rui: Yes

DJ: I know that from reading the documentation as well, for example, the target, the stuff that gets generated from an application programming perspective is, in the first incarnation, Java, but, you know, I can equally imagine ...

Rui: NodeJS

DJ: NodeJS, for example - and may be, I'm fishing here, maybe you know, when ABAP on the Cloud Platform goes GA, maybe generating some ABAP stuff as well? Is that in our vision?

Rui: To be sure, I don't know.

DJ: I think that would be quite cool.

Rui: Yeah, in essence the underlying technologies are the same, right, the model is very similar

DJ: It's a pattern, isn't it

Rui: Yeah, so most probably yes, but I'm not sure if it's on the roadmap.

DJ: No, OK, that's cool. So, you were talking about the general way things work, and it seems to me as well, correct me if I'm wrong, this is probably the nearest we are so far to, what am I going to call it, a cloud native programming model. Because, if I understand it correctly, I was looking at what the Web IDE was doing for me, which seemed to be a lot, while following this tutorial, the assets that are created and deployed are deployed to Cloud Foundry on the SAP Cloud Platform, is that right?

Rui: Yes, it is.

DJ: Because that seems to be to be exactly the direction we should be looking at going, right?

Rui: Yeah, so it's open, right, and you can in theory create any, or leverage any other programming language, right ... as you said, we are now starting with Java, NodeJS, and in general what we always look at is what are the programming languages that our customers demand most, and we certainly need to focus, right? To get things right, to start with Java first, because still, although we have all the other cool programming languages out there, I think there is still a huge community around Java. NodeJS ...

DJ: That's growing ...

RuiL: It's growing a lot, but it's better to have at least one programming language kind of complete, right, instead of having stuff just half baked on two programming languages.

DJ: I agree. Much as I would like, if not prefer, personally, to see NodeJS, I'm not the world's biggest fan of Java per se, but I value the whole idea of getting something first, and then expand.

Rui: Who knows what happens in the next months, you never know!

DJ: Woo, sounds exciting!

Rui: Stuff coming kind of, soon ...

DJ: No, that sounds good, that sounds quite exciting. Actually, talking about soon, or next, I think it's fair to say that this is, for people like me, you know, like regular on-the-street developers, who have been doing stuff in the SAP ecosphere, it's quite a bit step, right, quite a big step to this new world. What would you recommend developers like me do to move closer to, and take the next step in this direction?

Rui: I think initially really looking into CDS in general, to make yourself familiar, what CDS is, what it does, and I think, the best thing that you can do is take, for example, such an example in the help.sap.com web page, the bookstore example: Going through the tutorial, and then trying it out to make it work, and then actually modifying it, as long as you break it, and then getting to the next stage and saying OK, now I think I know how it works ... let me try to not do the straightforward way, right, let me say OK, now this stuff is generated for me, I would like to have some modifications in terms of: If I'm updating the table, or if I'm adding new rows to that table, before, I would like to execute my own code, right, and then finding out how these extension points work in the programming model. And then going to the next step, right, making it work, and then you modify, or you improve it until you break it, and then getting to the next stage

DJ: That reminds me, one of the parodies of the O'Reilly books, called O'Rly, that you see sometimes on Twitter, and my favourite one is: "Developing: Changing things and seeing what happens". And I think that's basically what you were saying, in a roundabout way.

Rui: I would say, still ... I have a young boy from school here with me, seventeen years old, and I think still it's important to have some basics, right? So that you know the technologies, you know how certain things work, and really ... yes, there's a craft[man]ship that you have to go through, but if you have that stage to really, now, find out how SAP technologies work, that's how I normally work, so I hope I have the foundation, and then I say OK, instead of reading books, how it should work, I just try it out. Then I just try crazy stuff, and then I find out oh - maybe I completely misunderstood the whole concept, and that's I think where you get to the next level, to really understand where this difference is coming from.   

DJ: In fact you've mentioned something that we'll pick up another time, because we've run out of time now, but - extension points ... that reminds me a little of the actions, determinations and validations in the BOPF world, on the ABAP programming model side, but ...

Rui: Let me tell you a secret

DJ: Go on, tell me a secret

Rui: I can't do any ABAP

DJ: What?!

Rui: But keep that secret, don't tell anybody!

DJ: And on that bombshell ...  Rui - I'm going to press STOP now, thank you very much!