Application start fails with NullPointerException because of MicrometerRecorder changes (3.3.0)

[holomekc]

Describe the bug

With Quarkus 3.3.0 our application cannot start anymore and fails with a NullPointerException:

Caused by: java.lang.NullPointerException: Cannot invoke "java.util.List.size()" because "classSpecificCustomizers" is null
	at io.quarkus.micrometer.runtime.MicrometerRecorder.configureRegistries(MicrometerRecorder.java:99)
	at io.quarkus.deployment.steps.MicrometerProcessor$configureRegistry477897979.deploy_0(Unknown Source)
	at io.quarkus.deployment.steps.MicrometerProcessor$configureRegistry477897979.deploy(Unknown Source)

We have a custom MeterRegistry (DynatraceMeterRegistry). We configured it exactly like this:
https://quarkus.io/guides/telemetry-micrometer#create-a-customized-meterregistry

After debugging I could see that registryClasses

quarkus/extensions/micrometer/runtime/src/main/java/io/quarkus/micrometer/runtime/MicrometerRecorder.java

Line 65 in 2c6f8b8

Set<Class<? extends MeterRegistry>> registryClasses,

Only contains two registries:

• PrometheusMeterRegistry
• JsonMeterRegistry

But in this line:

quarkus/extensions/micrometer/runtime/src/main/java/io/quarkus/micrometer/runtime/MicrometerRecorder.java

Line 80 in 2c6f8b8

Set<Bean<?>> beans = new HashSet<>(beanManager.getBeans(MeterRegistry.class, Any.Literal.INSTANCE));

Quarkus finds three beans:

1. PrometheusMeterRegistryProducer...
2. JsonMeterRegistryProvider...
3. DynatraceMicrometerRegistry...

The loop over the beans with three entries then tries to find the classSpecificCustomizers for DynatraceMeterRegistry:

quarkus/extensions/micrometer/runtime/src/main/java/io/quarkus/micrometer/runtime/MicrometerRecorder.java

Line 97 in 2c6f8b8

var classSpecificCustomizers = classMeterRegistryCustomizers.get(registryClass);

This returns null, which results in a NullPointerException in line:

quarkus/extensions/micrometer/runtime/src/main/java/io/quarkus/micrometer/runtime/MicrometerRecorder.java

Line 99 in 2c6f8b8

globalMeterRegistryCustomizers.size() + classSpecificCustomizers.size());

Expected behavior

Our application can start as usual 😉 .

Actual behavior

See bug description.

How to Reproduce?

See bug description.

Output of uname -a or ver

Darwin 22.5.0 Darwin Kernel Version 22.5.0: Thu Jun 8 22:22:22 PDT 2023; root:xnu-8796.121.3~7/RELEASE_X86_64 x86_64

Output of java -version

openjdk 17.0.7 2023-04-18 LTS

GraalVM version (if different from Java)

No response

Quarkus version or git rev

3.3.0

Build tool (ie. output of mvnw --version or gradlew --version)

Maven 3.9.2

Additional information

No response

[holomekc]

I could find that these changes are introduced here:
fbd6e52#diff-60163295574610b7cbe78ad23a4f19555ed7cc535df755adda53998976c6279e

because of:
#32996

[mkouba]

CC @geoand

[quarkus-bot]

/cc @brunobat (micrometer), @ebullient (metrics,micrometer), @jmartisk (metrics)

[geoand]

Ouch... What a silly mistake on my part!

I'll fix it ASAP, sorry for the inconvenience.

[geoand]

If however you can provide a sample application, we can make sure that nothing else broke as well.