Error Encountered When Pulling AWS Resource Metrics

[pkumarsingh]

Hi There,

I am trying to use YACE exporter to fetch metrics from different AWS region.
While executing docker command to fetch apigateway resource metrics from multiple AWS region, YACE exporter is throwing below error:

Digest: sha256:a6a1ab925f2b03bcfc1bc5055535beb1d444d223cf8ddbe50c36f18fc712570d
Status: Downloaded newer image for quay.io/invisionag/yet-another-cloudwatch-exporter:v0.20.0-alpha
{"level":"info","msg":"Parse config..","time":"2020-09-10T15:42:39Z"}
{"level":"info","msg":"Startup completed","time":"2020-09-10T15:42:39Z"}
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0xd53ef7]

goroutine 9 [running]:
main.detectDimensionsByService(0xc00001f480, 0xc000519240, 0xc0003a8b80, 0xc, 0x10)
/opt/aws_cloudwatch.go:513 +0x2527
main.scrapeDiscoveryJobUsingMetricData(0xc00001e440, 0x4, 0x4, 0xc000024220, 0xa, 0xc00004a670, 0x1, 0x1, 0x0, 0x0, ...)
/opt/abstract.go:203 +0xc28
main.scrapeAwsData.func1(0xc0000243c0, 0x0, 0xc000328000, 0x1, 0x1, 0x0, 0x0, 0x0, 0xc0000243b8, 0xc00000c6e0, ...)
/opt/abstract.go:46 +0x317
created by main.scrapeAwsData
/opt/abstract.go:32 +0x642

Below is the docker command:
docker run -it --rm -v /home/ubuntu/monitoring/yace/aws-cred:/exporter/.aws/credentials -p 5000:5000 --name yace -v /home/ubuntu/monitoring/yace/config.yml:/root/config.yml quay.io/invisionag/yet-another-cloudwatch-exporter:v0.20.0-alpha

This error is coming when fetching metrics from eu-west-1 region in my AWS account.
Looking forward for the fix.

[pkumarsingh]

Any help would be appreciated :)

[jylitalo]

Just as a comment that details in panic() would point towards https://github.com/ivx/yet-another-cloudwatch-exporter/blob/bb2645ebcd402a43f5b2dbf477c81347a34adefa/aws_cloudwatch.go#L513 where the only real pointer is that
resource.Matcher. But I haven't played enough with API Gateways to be able to say why the Matcher is missing from there.
If you are willing to compile your own yace docker image, you could try something like this (just before line 513):

	if resource.Matcher == nil {
		log.Warningf("Matcher missing from %s ARN on %s service", resourceArn, *service)
		return dimensions
	}

It wouldn't solve the case, but it would give you some additional information for further debugging.

[udhos]

Please see this fixed bug #246

It is fixed on master.

Can you test it by building from master?