In this article we show how to use the CData API Server and with the ADO.NET Provider for Snowflake (or any of 190+ other ADO.NET Providers) to write SAPUI5 apps that leverage the capabilities of the Snowflake 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 Snowflake 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
Follow the steps below to begin producing secure Snowflake OData services:
Deploy
The API Server runs on your own server. On Windows, you can deploy using the stand-alone server or IIS. On a Java servlet container, drop in the API Server WAR file. See the help documentation for more information and how-tos.
The API Server is also easy to deploy on Microsoft Azure, Amazon EC2, and Heroku.
Connect to Snowflake
After you deploy the API Server and the ADO.NET Provider for Snowflake, provide authentication values and other connection properties needed to connect to Snowflake by clicking Settings -> Connections and adding a new connection in the API Server administration console.
To connect to Snowflake:
- Set User and Password to your Snowflake credentials and set the AuthScheme property to PASSWORD or OKTA.
- Set URL to the URL of the Snowflake instance (i.e.: https://myaccount.snowflakecomputing.com).
- Set Warehouse to the Snowflake warehouse.
- (Optional) Set Account to your Snowflake account if your URL does not conform to the format above.
- (Optional) Set Database and Schema to restrict the tables and views exposed.
See the Getting Started guide in the CData driver documentation for more information.
You can then choose the Snowflake entities you want to allow the API Server access to by clicking Settings -> Resources. This article uses Products as an example.
Authorize API Server Users
After determining the OData services you want to produce, authorize users by clicking Settings -> Users. The API Server uses authtoken-based authentication and supports the major authentication schemes. You can authenticate as well as encrypt connections with SSL. Access can also be restricted by IP address; Access is restricted to only the local machine by default.
Create the View
In this article the user views and interacts with Snowflake 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="{/Products}"
threshold="15"
enableBusyIndicator="true"
columns="{
path: 'meta>/dataServices/schema/[${namespace}===\'CData\']/entityType/[${name}===\'Products\']/property',
factory: '.columnFactory'
}">
<toolbar>
<m:Toolbar>
<m:Title text="Snowflake Products"></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 Snowflake 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: "{/#Products/" + 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>Snowflake Products</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: "Snowflake Products",
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 Snowflake data. You can now browse and search current Snowflake data.
