NullPointer during Rest client creation when micrometer is disabled

[danielmaison]

Describe the bug

NullPointer is thrown if micrometer is included but disabled when RestClient is created.

Expected behavior

Application to work as usual, but without metrics reported

Actual behavior

Nullpointer during RestClient creation

Caused by: java.lang.NullPointerException
    at io.quarkus.micrometer.runtime.binder.RestClientMetricsListener.prepClientMetrics(RestClientMetricsListener.java:50)
    at io.quarkus.micrometer.runtime.binder.RestClientMetricsListener.onNewClient(RestClientMetricsListener.java:38)
    at io.quarkus.restclient.runtime.QuarkusRestClientBuilder.lambda$build$0(QuarkusRestClientBuilder.java:236)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)
    at io.quarkus.restclient.runtime.QuarkusRestClientBuilder.build(QuarkusRestClientBuilder.java:236)
    at io.quarkus.restclient.runtime.RestClientBase.create(RestClientBase.java:72)

How to Reproduce?

Reproducing project:
https://github.com/danielmaison/quarkus-micrometer-bug

Simple Quarkus project generated with Quarkus 2.8.1.Final and extensions:

• quarkus-resteasy (classic)
• quarkus-resteasy-jsonb
• quarkus-rest-client-jsonb
• quarkus-micrometer-registry-prometheus

Changes made to sample code

1. application.properties - disabled micrometer
2. Added Rest client interface with empty get method
3. In Server rest resource, inject rest client

Reproduce by: Calling server resource (e.g. via test)

Output of uname -a or ver

Linux Desktop 5.10.60.1-microsoft-standard-WSL2 #1 SMP Wed Aug 25 23:20:18 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

Output of java -version

openjdk 11.0.14.1 2022-02-08 OpenJDK Runtime Environment (build 11.0.14.1+1-Ubuntu-0ubuntu1.20.04) OpenJDK 64-Bit Server VM (build 11.0.14.1+1-Ubuntu-0ubuntu1.20.04, mixed mode, sharing)

GraalVM version (if different from Java)

N/A

Quarkus version or git rev

2.8.1.Final

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

Apache Maven 3.8.4

Additional information

No response

[quarkus-bot]

/cc @ebullient, @michalszynkiewicz

[danielmaison]

Thank you for your quick response <3

[geoand]

Thanks for the reproducer, it was most helpful :)