panic: runtime error: index out of range [0] with length 0 for Wavefront output in Telegraf

Hi,
I have a telegraf(in docker container in Kubernetes) based service sending continuous stream of metrics to Wavefront through wavefront proxy.

The telegraf service getting crashed often with the below error and stop sending metrics to wavefront.

We are pulling the latest version of telegraf taz in our service docker file as below:

RUN curl --output telegraf.tar.gz https://dl.influxdata.com/telegraf/releases/telegraf-1.20.4_linux_amd64.tar.gz RUN tar --strip-components=2 -C / -xvvf telegraf.tar.gz

Telegraf version is telegraf-1.20.4

panic: runtime error: index out of range [0] with length 0

goroutine 354 [running]:
github.com/wavefronthq/wavefront-sdk-go/senders.sanitizeInternal({0x0, 0x0})
	/go/pkg/mod/github.com/wavefronthq/wavefront-sdk-go@v0.9.7/senders/formatter.go:340 +0x2d5
github.com/wavefronthq/wavefront-sdk-go/senders.MetricLine({0xc00d09eb20, 0xc00b3f9b00}, 0xc00b3f9b00, 0x61ccb037, {0xc00db72900, 0x24}, 0x6000103, {0xc00083c000, 0x2a})
	/go/pkg/mod/github.com/wavefronthq/wavefront-sdk-go@v0.9.7/senders/formatter.go:56 +0x3ae
github.com/wavefronthq/wavefront-sdk-go/senders.(*directSender).SendMetric(0xc00081a0f0, {0xc00d09eb20, 0xc017249e30}, 0x40ead4, 0x0, {0xc00db72900, 0xfa00}, 0x0)
	/go/pkg/mod/github.com/wavefronthq/wavefront-sdk-go@v0.9.7/senders/direct.go:84 +0x48
github.com/influxdata/telegraf/plugins/outputs/wavefront.(*Wavefront).Write(0xc0007bf550, {0xc03e15e000, 0xfa0, 0x0})
	/go/src/github.com/influxdata/telegraf/plugins/outputs/wavefront/wavefront.go:172 +0x1dc
github.com/influxdata/telegraf/models.(*RunningOutput).write(0xc0002bd880, {0xc03e15e000, 0xfa0, 0xfa0})
	/go/src/github.com/influxdata/telegraf/models/running_output.go:244 +0x118
github.com/influxdata/telegraf/models.(*RunningOutput).WriteBatch(0xc0002bd880)
	/go/src/github.com/influxdata/telegraf/models/running_output.go:218 +0x58
github.com/influxdata/telegraf/agent.(*Agent).flushOnce.func1()
	/go/src/github.com/influxdata/telegraf/agent/agent.go:829 +0x29
created by github.com/influxdata/telegraf/agent.(*Agent).flushOnce
	/go/src/github.com/influxdata/telegraf/agent/agent.go:828 +0xb8

Note: Also this error is not resolved even with latest telegraf version 1.21.1

Please help us to resolve this issue.

Start at plugins/outputs/wavefront/wavefront.go, especially Write, and inspect the wavefront-sdk-go formatter.go call to sanitizeInternal shown in the stack trace. Reproduce with the reported Telegraf versions and Wavefront output setup, then determine which empty input causes the panic. Done means the output no longer crashes and the failure has a regression test.