You will learn
Now that you have a basic application and service created you can now do a bit more dynamic displaying of the your data.
Internet of Things (IoT) Viewing your Tessel data in a dynamic graph
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Internet of Things (IoT) Viewing your Tessel data in a dynamic graph
By Craig Cmehil
Now connect your IoT Services to an SAP HANA MDC instance and show the data using SAP HANA XS
Details
[ACCORDION-END]
Step 1: Open sub package

Return to the “SAP HANA Web-based Development Workbench” and go to the “sub package” - codejam.iotmmsxs
Step 2: Create new file

Right click and create a new file called graph.html. You will use the following code to display your data now in a graph as opposed to the table from the previous tutorial. There are a ton of open source and other libraries out there for creating graphs, below is a simple use of the canvas tag.
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8" />
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="viewport" content="width=device-width,initial-scale=1">
<script id='sap-ui-bootstrap'
src='/sap/ui5/1/resources/sap-ui-core.js'
data-sap-ui-theme='sap_goldreflection'
data-sap-ui-libs='sap.ui.core,sap.ui.commons,sap.ui.table'>
</script>
<style>
.canvas {
margin:5px;
border-radius: 10px;
border:3px solid #003283;
}
</style>
</head>
<body>
<canvas class="canvas" id="myCanvas" width="800" height="400"></canvas>
<script>
var canvas = document.getElementById('myCanvas');
var context = canvas.getContext('2d');
context.beginPath();
context.rect(300, 400-1, 200, 1);
context.fillStyle = 'gold';
context.fill();
context.lineWidth = 2;
context.stroke();
setInterval(function() {
// Do something every 1 seconds
getLatestValue();
}, 1000);
function getLatestValue(){
var aData;
$.ajax({
type: "GET",
url: "/codejam/iotmmsxs/services/iotservice.xsodata/T_IOT_15B1E994B520C8D65A42?$format=json&$orderby=C_TIMESTAMP desc&$top=1",
dataType: 'json',
async: false,
success: function (data, status){
aData = data.d.results[0]['C_TEMPERATURE'];
}
});
console.log("Called for data");
redraw(aData);
}
function redraw(aData){
// clear the canvas
context.clearRect(0,0,canvas.width,canvas.height);
// redraw one or more things based on their javascript objects
context.beginPath();
context.rect(300, 400-aData*10, 200, aData*10);
context.fillStyle = 'gold';
context.fill();
context.lineWidth = 2;
context.stroke();
context.closePath();
context.font="40px Georgia";
context.strokeText(aData+'C',10,50);
}
</script>
</body>
</html>
Next Steps
- Select a tutorial from the Tutorial Navigator or the Tutorial Catalog