NullPointerException when no local ip in Span

[rafal-dudek]

Describe the Bug

When localIP is missing in Server braveSpan, it causes exception:

java.lang.NullPointerException: Cannot invoke "String.length()" because "ipString" is null
	at com.google.common.net.InetAddresses.ipStringToBytes(InetAddresses.java:185)
	at com.google.common.net.InetAddresses.forString(InetAddresses.java:151)
	at zipkin2.reporter.stackdriver.brave.AttributesExtractor.extract(AttributesExtractor.java:76)
	at zipkin2.reporter.stackdriver.brave.SpanTranslator.translate(SpanTranslator.java:80)
	at zipkin2.reporter.stackdriver.brave.StackdriverV2Encoder.translate(StackdriverV2Encoder.java:59)
	at zipkin2.reporter.stackdriver.brave.StackdriverV2Encoder.sizeInBytes(StackdriverV2Encoder.java:31)
	at zipkin2.reporter.stackdriver.brave.StackdriverV2Encoder.sizeInBytes(StackdriverV2Encoder.java:15)
	at zipkin2.reporter.internal.CountBoundedQueue.doDrain(CountBoundedQueue.java:115)
	at zipkin2.reporter.internal.CountBoundedQueue.drainTo(CountBoundedQueue.java:83)
	at zipkin2.reporter.internal.AsyncReporter$BoundedAsyncReporter.flush(AsyncReporter.java:241)
	at zipkin2.reporter.internal.AsyncReporter$Flusher.run(AsyncReporter.java:352)
	at java.base/java.lang.Thread.run(Thread.java:1583)

Steps to Reproduce

Make sure that your Server Span is missing local IP address.
Not sure how to reproduce it exactly - the problem occurs in our Integration tests only in Jenkins Agent on Kubernetes, locally the IP address is present.
In our case it is for Spring Boot 3.3.2 MVC RestController span.

Expected Behaviour

There should be check if braveSpan.localIp()!=null before invoking InetAddresses.forString(String ipString) on it:
https://github.com/openzipkin/zipkin-gcp/blob/master/encoder-stackdriver-brave/src/main/java/zipkin2/reporter/stackdriver/brave/AttributesExtractor.java#L76

If localIP is null, do not set any attribute for it.

[sann3]

We are also facing this issue
Spring boot - 3.3.2
com.google.cloud:spring-cloud-gcp-dependencies - 5.5.0
org.springframework.cloud:spring-cloud-dependencies - 2023.0.3

[shakuzen]

Anyone up for making a pull request to fix this and add tests for it? Looks like the AttributesExtractor used by the other encoder has null checks for IP:

zipkin-gcp/translation-stackdriver/src/main/java/zipkin2/translation/stackdriver/AttributesExtractor.java

Lines 64 to 71 in 829844a

	if (zipkinSpan.localEndpoint().ipv4() != null) {
	attributes.putAttributeMap(
	getLabelName("endpoint.ipv4"), toAttributeValue(zipkinSpan.localEndpoint().ipv4()));
	}
	if (zipkinSpan.localEndpoint().ipv6() != null) {
	attributes.putAttributeMap(
	getLabelName("endpoint.ipv6"), toAttributeValue(zipkinSpan.localEndpoint().ipv6()));
	}

[hjed]

We get this problem when running spring on cloud run

[shakuzen]

Would folks affected by this be able to test with snapshots to confirm there aren't any remaining issues with the fix now merged?

[hjed]

We've tested with Os's PR and it fixes the issue for us, thanks

[ccudennec-otto]

oh, that's great to hear! 🥳
how is your release schedule? when can we expect the fix to be released?

[shakuzen]

Releases for this repo are ad hoc. I'll try to find time to do a release this week.

[shakuzen]

With #226 merged, I think we have everything ready for the release. If anyone would like to try out snapshots before the release to make sure everything is good, that'd be appreciated.

[joaotab]

I tried the 2.2.5-SNAPSHOT and it worked for our deployment

[shakuzen]

2.2.5 is released now with this fix.