On 10th of March the fourth SAP Inside Track Frankfurt took place. As previous event we decided to offer two code Jams in parallel – and SAP made it possible. In an SAP Code Jam the participants get hands on experience with SAP’s latest technology by doing some tutorials.
SAP Code Jam HANA XSA
For the ones who don’t know about SAP HANA XSA here is a short explanation. It is a full featured application server, web server, and development environment within the SAP HANA appliance itself. The perfect use case is a platform for microservices that benefit form HANA as database. Those Microservices can be developed in several programming languages like Java or JavaScipt (NodeJS). The development paradigm is different from the ABAP-based one in the digital core. If you are interested, you can read about this paradigm in https://12factor.net/ .The following blog provides a good introduction: https://blogs.sap.com/2017/09/04/xs-advanced-for-not-so-dummies/ .
Such principles are always somewhat abstract to for me it was important to get a feeling about the development workflow. Many of those things are quite familiar: defining a data model using HANA CDS, adding database logic, expose everything as XSOData and put a Fiori App on top of it.
We learned many new things like the application space hierarchy, App Router which routes to those Microservices for example. Of course we learned who the whole development tools felt like. In fact HANA Studio is obsolete and we used SAP Web IDE for SAP HANA.
For the Code Jam you need SAP HANA Express which is available as cloud offering. There are several cloud providers that offer this installation and some of them have a special offer for trial customers so that you don’t have to pay anything. To work with this instances you need a browser and a ssh tool. So you have to make sure that you can access the system in the could with https and ssh using various ports.
The exercises are not that difficult. If you have basic knowledge above mentioned programming languages you have good chances to master all exercises. If you have advanced skills feel free to develop your own project in a hackathon style. Marc Becker and his team helped if we had some trouble with the exercises.
I enjoyed the event and I can recommend to anyone who is interested are interested in modern programming paradigms and HANA native programming.
Code Jam SAP Gateway
The topic of the second SAP Code Jam was SAP Gateway. In my opinion this is still a very important topic: if you are a Fiori developer this CodeJam will help you to understand the backend development. If you already have some Gateway skills this CodeJam probably will teach you some new stuff. Why? The Gateway programming model changed during the time. It started with hub-based development using RFCs and Web Services. Later we did manual programming using SEGW and nowadays we develop services based on SADL models using auto-exposure of CDS resp. BOPF models. There are some use cases where auto-exposure is not appropriate und you should use RDS. RDS is comparable to auto-exposure but you can define a model and have the generated classes so that you can add your own code when necessary.
IMHO every Gateway developer has to know all those possibilities and should know about best practices, otherwise the implementation of OData services will most likely fail or will be much too expensive. For the exercises SAP has a demo AS ABAP in the cloud – you need only a browser and ABAP on Eclipse on your laptop to connect to AS ABAP.
André Fischer form SAP is a great coach and can offer special exercises for each scenario.
For lunch we went to the canteen at AOK Systems.