# Expose Ignition tags to WebDev applications

**URL:** <https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338>\
**Category:** Ignition\
**Created:** [November 10, 2016, 2:22am UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338 "2016-11-10T02:22:17Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![richardNZ15](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/richardnz15/32/33373_2.png) [@richardNZ15](https://forum.inductiveautomation.com/u/richardNZ15)\
**Post date:** [November 10, 2016, 2:22am UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338/1 "2016-11-10T02:22:17Z")

</div>

I have successfully created a simple WebApp written in HTML / javascript which is hosted on the ignition gateway via the WebDev module.

I have used ajax GET and POST methods in the WebApp to talk to SQL tables via python resources.

What i am trying to do now is be able to write a GET / POST script in python resource that will allow me to read and write Ignition tags from the WebApp.

I tried a basic example of sending a tagPath string from the WebApp and tried reading the tag and sending the value back. But ran into the issue of not being able to pass “/” as part of a tagPath variable in an ajax GET method.

What is the best way to properly expose tags to a web interface?

Here is the example i have tried, hardcoding the tagPath into the python resource directly (still doesn’t work).

Javascript code in WebApp:

```auto
function.getTag(tagPath){
    formData = {"tagPath": tagPath};

    $.ajax({
        type: "GET", 
        url: "../python/tag",
        data: formData,
        success: function(result){
            console.log(result);
        },
        error: function(){
            console.log("Error with getTag function");
        },
        contentType: "application/x-www-form-urlencoded"
    });
}

```

Python GET method Code in Ignition WebDev module ‘tag’ resource:

```auto
def doGet(request, session):
	import system
	
	#tagPath = request['params']['tagPath']
	#tagVal = system.tag.read('temp/'+tagPath).value
	
	tagVal = system.tag.read('temp/testMemReal').value
	return {'json': system.util.jsonEncode(tagVal)}
```

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<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [November 10, 2016, 5:31am UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338/2 "2016-11-10T05:31:09Z")

</div>

Have you tried using the tag provider in the tag path?

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<div class="post-metadata">

**Author:** ![richardNZ15](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/richardnz15/32/33373_2.png) [@richardNZ15](https://forum.inductiveautomation.com/u/richardNZ15)\
**Post date:** [November 11, 2016, 2:09am UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338/3 "2016-11-11T02:09:54Z")

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Ah yep, adding [default] to start of the tagpath worked, and i can now read and write tags.  
Awesome, thanks!

Is it possible to read and write Array or Dataset tags through this method? Doesn’t seem to be working.

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<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [November 11, 2016, 2:58am UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338/4 "2016-11-11T02:58:22Z")

</div>

Not sure… might need to be on 7.9 for it to work.

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<div class="post-metadata">

**Author:** ![kjsubbu](https://avatars.discourse-cdn.com/v4/letter/k/e47c2d/32.png) [@kjsubbu](https://forum.inductiveautomation.com/u/kjsubbu)\
**Post date:** [April 23, 2017, 6:15pm UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338/5 "2017-04-23T18:15:54Z")

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HI Kevin,

Can you please help the value what i have to place in tagpath…

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<div class="post-metadata">

**Author:** ![Maheswaran\_S](https://avatars.discourse-cdn.com/v4/letter/m/e47c2d/32.png) [@Maheswaran\_S](https://forum.inductiveautomation.com/u/Maheswaran_S)\
**Post date:** [January 13, 2023, 3:12am UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338/6 "2023-01-13T03:12:36Z")

</div>

@Kevin.Herron  
i want to update tag history data into the chart with ajax but i couldn't update the next data into the ajax, can you please help me on that

i have updated the code below

```auto
	endTime = system.date.now()
	startTime = system.date.addMinutes(endTime, -30)
	path1 =['[SPA_SCADA]WB001/FIN001/Bpl1/FP001/BOO001/Status/Actual_Speed'] 
	dataSet = system.tag.queryTagHistory(paths=path1, startDate=startTime, endDate=endTime, returnSize=10, aggregationMode="Maximum", returnFormat='Wide')
	pydata = system.dataset.toPyDataSet(dataSet)
	t_stamp = map(lambda row: str(row[0]),pydata)
	speed = map(lambda row: str(round(row[1],1)),pydata)
#	return{'json':{'t_Stamp1':str(t_stamp),'speed1':str(speed)}}
	

	html = """
	<html>
	<body>
	<script src="https://cdn.jsdelivr.net/npm/apexcharts"></script>
	<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.1/jquery.min.js"></script>
	
	<div id="chart"></div>
	<script type="text/javascript">

        var options = {
          series: [
          {
            name: "Speed",
            data: """+str(speed)+"""
          }
        ],
          chart: {
          height: 350,
          type: 'line',
          dropShadow: {
            enabled: true,
            color: '#000',
            top: 18,
            left: 7,
            blur: 10,
            opacity: 0.2
          },
          toolbar: {
            show: false
          }
        },
        colors: ['#77B6EA', '#545454'],
        dataLabels: {
          enabled: true,
        },
        stroke: {
          curve: 'smooth'
        },
        title: {
          text: 'Average High & Low Temperature',
          align: 'left'
        },
        grid: {
          borderColor: '#e7e7e7',
          row: {
            colors: ['#f3f3f3', 'transparent'], // takes an array which will be repeated on columns
            opacity: 0.5
          },
        },
        markers: {
          size: 1
        },
        xaxis: {
          categories: """+str(t_stamp)+""",

        },
        yaxis: {
          title: {
            text: 'Temperature'
          },
          min: 5,
          max: 250
        },
        legend: {
          position: 'top',
          horizontalAlign: 'right',
          floating: true,
          offsetY: -25,
          offsetX: -5
        }
        };

        var chart = new ApexCharts(document.querySelector("#chart"), options);
        chart.render();
        
			function updateChartSeries() {
			  
			  // Replace data to existing Chart
			  chart.updateSeries([
			    {
			      name: "Speed",
			      data: """+str(speed)+"""
			    }
			  ]);
			}
        
        setInterval(updateChartSeries,1000);

```

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<div class="post-metadata">

**Author:** ![richardNZ15](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/richardnz15/32/33373_2.png) [@richardNZ15](https://forum.inductiveautomation.com/u/richardNZ15)\
**Post date:** [May 22, 2023, 11:41pm UTC](https://forum.inductiveautomation.com/t/expose-ignition-tags-to-webdev-applications/12338/8 "2023-05-22T23:41:16Z")

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This has got nothing to do with the topic, you should start a new topic with your question..