Cannot read properties of undefined

Grafana Plugin Development
1

Hello,
I am using plugins like:

  1. Apache ECharts plugin for Grafana | Grafana Labs
  2. Echarts plugin for Grafana | Grafana Labs
    for data visualization.

When there is no data to be returned from the flux query the following message I got:

image
image1545×527 77.9 KB

Can you please tell me, how should I modify the code related to the chart, to display more user friendly content?

This function does not run because there is no data:

const series = data.series.map((s, index) => {
const sData = s.fields.find((f) => f.type === ‘number’).values.buffer;
const sTime = s.fields.find((f) => f.type === ‘time’).values.buffer;

return {
name: s.refId,
type: ‘line’,
showSymbol: false,
lineStyle: {
width: 1,
color: colors[mod(index, colors.length)],
},
data: sData.map((d, i) => [sTime[i], d.toFixed(2)]),
};
});

When I change the series to this one:

const series = ;

I got the right output like this:

image
image1283×456 2.91 KB

How can I manage the value of the series to display empty content when there is no data to run the map function?

Thank you!

1 Like
2

You will need to check to see if your data has any value if so return what you have if not return an empty array

3

Hello,
Yes, that was obvious for me, but I don’t know how to do that in the code. For example, when I change the ‘series’ variable to this ‘’ - got the following exception: Unexpected token ‘]’

Can you provide an example code?

5

Hey,
It is a little bit more complicated, but you pointed me to the right direction.

image
image576×648 51.8 KB

Only the last 2 series are undefined. Thank you!

1 Like