Within term Gateway we
need to be careful. SAP Basis people know this term as component of SAP NW ABAP
and JAVA app servers which handles the SAP proprietary RFC protocol. The
gateway is specified in RFC connections as hostname where program ID runs. It
is e.g. used by outbound IDoc which are send form SAP system. Maybe you know
Tcodes like SMGW where you can monitor the gateway.
On
other hand we have here something which is called SAP NetWeaver Gateway
(NW GW). What is "SAP NetWeaver Gateway" then? It is SAP
NetWeaver ABAP AS based solution introduced in 2011 based on open standards
(e.g. OData) which can be used to more easily connect non SAP applications to
SAP applications and vice versa. The NW GW can be used to connect to SAP
backend applications by using any programming language or model without the
need for SAP knowledge. This is achieved by leveraging REST services and OData
and ATOM protocols, according to SAP. Formerly the solution’s name was changed
in 2014. The NetWeaver abbreviation was dropped and now it is called just SAP Gateway (GW).
We
can say about the GW that it is ODATA for Enterprise. Basically what it does is
nothing else just exposing the data residing in SAP application to outside
world. Of course this was possible long time before GW was introduced. But what
is advantage of GW is that instead of using SAP’s proprietary RFC functions
(also known as BAPI)
standard opens source technologies (OData) are used.
Let
just introduce OData briefly by quoting Wikipedia: OData is data access protocol to provide standard
CRUD (Create/Read/Update/Delete) access to a data source via a website. It is
similar to JDBC and ODBC although OData is not limited to SQL databases. It is
kind of ODBC for web means data is accessible via URLs (e.g. http://:/sap/opu/sdata/iwfnd/RMTSAMPLEFLIGHT/$metadata?$format=xml).
OData is designed to provide implementation of RESTful API for creating and
consuming data APIs. Also it is multichannel means they can serve data to
multiple apps from one logical model. OData is extensible so by using GW; SAP
allows to supplement OData data types within information from ABAP data dictionary.
By using GW we can get SAP
data to every environment, tool or device. GW supports developers to create apps
that connect to SAP software.
How GW application looks
like? There is a data abstraction part residing on GW server – service model (structure
of OData). This is developed in OData Modeler- a plugin to Eclipse
also part residing on GW server The service is implemented by binding to data
sources (e.g. SAP ECC). There is a GW’s Service Builder to develop that. The service
has its implementation and business logic. In order to consume OData there is external
app e.g. created JAVA/PHP/JSE/iOS/Android/HTML5 e.g. in Eclipse.
From licensing point of
view notice that external app is supposed to communicate with SAP backend (via
GW) by using so called SAP Gateway User. Which is named user (SAP terminology, see
more here) authorized to use licensed software from SAP.
To download and install trial version of SAP NetWeaver
Gateway kindly follow my other blog: SAP
NetWeaver Application Server ABAP 7.02 SP11 with Gateway SP04 Trial - Ready for
SAP Gateway
More information:
1 comment:
Great Blog, i am really enjoyably reading your blog,keep sharing this kind of articles.
Post a Comment