Integrate Real-Time Access to REST in SAPUI5 MVC Apps

Use the built-in ODataModel class in SAPUI5 to create Web apps that reflect changes to REST data in real time.

In this article we show how to use the CData API Server to write SAPUI5 apps that leverage the capabilities of the REST API, without writing to a back-end database. The API Server is a lightweight Web application that runs on your server and produces OData feeds of REST data. OData is the standard for real-time data access over the Web and has built-in support in SAPUI5 and OpenUI5.

Set Up the API Server

If you have not already done so, download the CData API Server. Once you have installed the API Server, follow the steps below to begin producing secure REST OData services:

Connect to REST

To work with REST data from SAPUI5, we start by creating and configuring a REST connection. Follow the steps below to configure the API Server to connect to REST data:

First, navigate to the Connections page.
Click Add Connection and then search for and select the REST connection.
Enter the necessary authentication properties to connect to REST.
See the Getting Started chapter in the data provider documentation to authenticate to your data source: The data provider models REST APIs as bidirectional database tables and XML/JSON files as read-only views (local files, files stored on popular cloud services, and FTP servers). The major authentication schemes are supported, including HTTP Basic, Digest, NTLM, OAuth, and FTP. See the Getting Started chapter in the data provider documentation for authentication guides.

After setting the URI and providing any authentication values, set Format to "XML" or "JSON" and set DataModel to more closely match the data representation to the structure of your data.

The DataModel property is the controlling property over how your data is represented into tables and toggles the following basic configurations.
- Document (default): Model a top-level, document view of your REST data. The data provider returns nested elements as aggregates of data.
- FlattenedDocuments: Implicitly join nested documents and their parents into a single table.
- Relational: Return individual, related tables from hierarchical data. The tables contain a primary key and a foreign key that links to the parent document.
See the Modeling REST Data chapter for more information on configuring the relational representation. You will also find the sample data used in the following examples. The data includes entries for people, the cars they own, and various maintenance services performed on those cars.
After configuring the connection, click Save & Test to confirm a successful connection.

Configure API Server Users

Next, create a user to access your REST data through the API Server. You can add and configure users on the Users page. Follow the steps below to configure and create a user:

On the Users page, click Add User to open the Add User dialog.
Next, set the Role, Username, and Privileges properties and then click Add User.
An Authtoken is then generated for the user. You can find the Authtoken and other information for each user on the Users page:

Creating API Endpoints for REST

Having created a user, you are ready to create API endpoints for the REST tables:

First, navigate to the API page and then click Add Table .
Select the connection you wish to access and click Next.
With the connection selected, create endpoints by selecting each table and then clicking Confirm.

Gather the OData Url

Having configured a connection to REST data, created a user, and added resources to the API Server, you now have an easily accessible REST API based on the OData protocol for those resources. From the API page in API Server, you can view and copy the API Endpoints for the API:

Create the View

In this article the user views and interacts with REST data through an SAPUI5 table control. Table columns will be automatically detected from the metadata retrieved from the API Server's API endpoint. We define the following table in a separate View.view.xml file:


<mvc:View
  controllerName="sap.ui.table.sample.OData2.Controller"
  xmlns="sap.ui.table"
  xmlns:mvc="sap.ui.core.mvc"
  xmlns:u="sap.ui.unified"
  xmlns:c="sap.ui.core"
  xmlns:m="sap.m">
  <m:Page
    showHeader="false"
    enableScrolling="false"
    class="sapUiContentPadding">
    <m:content>
      <Table
        id="table"
        selectionMode="MultiToggle"
        visibleRowCount="10"
        enableSelectAll="false"
        rows="{/people}"
        threshold="15"
        enableBusyIndicator="true"
        columns="{
          path: 'meta>/dataServices/schema/[${namespace}===\'CData\']/entityType/[${name}===\'people\']/property',
          factory: '.columnFactory'
        }">
        <toolbar>
          <m:Toolbar>
            <m:Title text="REST people"></m:Title>
          </m:Toolbar>
        </toolbar>
        <noData>
          <m:BusyIndicator class="sapUiMediumMargin"/>
        </noData>
      </Table>
    </m:content>
  </m:Page>
</mvc:View>

Create the Model and Controller

In SAPUI5, you do not need to write any OData queries; an ODataModel instance handles the application's data access commands. The API Server then translates the queries into REST API calls.

The controller processes user input and represents information to the user through a view. Define the controller in a new file, Controller.controller.js. Instantiate the model in the onInit function -- you will need to replace the placeholder values for the URL to the API Server, a user allowed to access the OData endpoint of the API Server, and the authtoken for the user.

sap.ui.define([
  "sap/ui/core/mvc/Controller",
  "sap/ui/model/odata/v2/ODataModel",
  "sap/ui/model/json/JSONModel",
  "sap/ui/table/Column",
  "sap/m/Text",
], function(Controller, ODataModel, JSONModel, Column, Text ) {
  "use strict";
  

  return Controller.extend("sap.ui.table.sample.OData2.Controller", {
    
    onInit : function () {
      
      var oView = this.getView();
      var oDataModel = new ODataModel("http://myserver/api.rsc/",{user: "MyUser", password: "MyAuthToken"});
      
      oDataModel.getMetaModel().loaded().then(function(){
        oView.setModel(oDataModel.getMetaModel(), "meta");
      });
      oView.setModel(oDataModel);
      
      var oTable = oView.byId("table");
      var oBinding = oTable.getBinding("rows");
      var oBusyIndicator = oTable.getNoData();
      oBinding.attachDataRequested(function(){
      oTable.setNoData(oBusyIndicator);
      });
      oBinding.attachDataReceived(function(){
        oTable.setNoData(null); //use default again ("no data" in case no data is available)
      });
    },
    
    onExit : function () {
    },
    
    columnFactory : function(sId, oContext) {
      var oModel = this.getView().getModel();
      var sName = oContext.getProperty("name");
      var sType = oContext.getProperty("type");
      var iLen = oContext.getProperty("maxLength");
      iLen = iLen ? parseInt(iLen, 10) : 10;
      
      return new Column(sId, {
        sortProperty: sName, 
        filterProperty: sName,
        width: (iLen > 9 ? (iLen > 50 ? 15 : 10) : 5) + "rem",
        label: new sap.m.Label({text: "{/#people/" + sName + "/@name}"}),
        hAlign: sType && sType.indexOf("Decimal") >= 0 ? "End" : "Begin",
        template: new Text({text: {path: sName}})
      });
    }
    
  });

});

Describe Application Logic

Create a component that contains the resources of your application. Define the following in Component.js:


sap.ui.define([
  'sap/ui/core/UIComponent'
], function(UIComponent) {
  "use strict";

  return UIComponent.extend("sap.ui.table.sample.OData2.Component", {
    metadata : {
      rootView : "sap.ui.table.sample.OData2.View",
      dependencies : {
        libs : [
          "sap.ui.table",
          "sap.ui.unified",
          "sap.m"
        ]
      },

      config : {
        sample : {
          stretch : true,
          files : [
            "View.view.xml",
            "Controller.controller.js"
          ]
        }
      }
    }
  });

});

Bootstrap OpenUI5 and Launch

To complete the MVC application, simply add the bootstrap and initialization code. Add these directly to index.html:

<!DOCTYPE HTML>

<html>
<head>
  <meta http-equiv="x-ua-compatible" content="ie=edge">
  <meta charset="utf-8"> 
  <title>REST people</title>
  
  <script id="sap-ui-bootstrap"
    src="https://openui5.hana.ondemand.com/resources/sap-ui-core.js"
    data-sap-ui-libs="sap.m"
    data-sap-ui-theme="sap_bluecrystal"
    data-sap-ui-xx-bindingSyntax="complex"
    data-sap-ui-preload="async"
    data-sap-ui-compatVersion="edge" 
    data-sap-ui-resourceroots='{"sap.ui.table.sample.OData2": "./", "sap.ui.demo.mock": "mockdata"}'>
  </script>
  
  <!-- application launch configuration -->
  <script>
  
      sap.ui.getCore().attachInit(function() {
        new sap.m.App ({
          pages: [
                new sap.m.Page({
                    title: "REST people", 
                    enableScrolling : false,
                  content: [ new sap.ui.core.ComponentContainer({
                  height : "100%", name : "sap.ui.table.sample.OData2"
                })]
            })
          ]
      }).placeAt("content");
    });

  </script>
</head> 
  <!-- UI Content -->
<body class="sapUiBody" id="content" role="application">
</body> 
</html>

The resulting SAPUI5 table control reflects any changes to a table in the remote REST data. You can now browse and search current REST data.

A table in SAPUI5 that reflects changes to the data in real time. (Salesforce is shown.)

Ready to get started?

Learn more or sign up for a free trial:

CData API Server