quarkus.otel.traces.sampler.arg doesn't support String value (e.g. cannot configure "jaeger_remote" sampler)

[calohmn]

Describe the bug

The Quarkus OpenTelemetry Configuration Reference mentions that the quarkus.* properties match the ones from the OpenTelemetry SDK Autoconfigure.

In the AutoConfigure SDK sampler configuration section, the otel.traces.sampler.arg property isn't explicitly restricted to having a number/double value.
In fact, in the OpenTelemetry Specification 1.25.0, section General SDK Configuration, the OTEL_TRACES_SAMPLER_ARG env var is described as possibly containing a comma separated list in case of the jaeger_remote and parentbased_jaeger_remote samplers.

But the quarkus.otel.traces.sampler.arg configuration property explicitly has a double type.

That means that a configuration of

quarkus.otel.traces.sampler: "jaeger_remote"
quarkus.otel.traces.sampler.arg: "endpoint=http://hono-jaeger:14250"

isn't supported and leads to this exception on startup:

ERROR: Failed to start application (with profile [prod])
java.lang.RuntimeException: Failed to start quarkus
	at io.quarkus.runner.ApplicationImpl.doStart(Unknown Source)
	at io.quarkus.runtime.Application.start(Application.java:101)
	at io.quarkus.runtime.ApplicationLifecycleManager.run(ApplicationLifecycleManager.java:111)
	at io.quarkus.runtime.Quarkus.run(Quarkus.java:71)
	at io.quarkus.runtime.Quarkus.run(Quarkus.java:44)
	at io.quarkus.runtime.Quarkus.run(Quarkus.java:124)
	at io.quarkus.runner.GeneratedMain.main(Unknown Source)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.base/java.lang.reflect.Method.invoke(Unknown Source)
	at io.quarkus.bootstrap.runner.QuarkusEntryPoint.doRun(QuarkusEntryPoint.java:61)
	at io.quarkus.bootstrap.runner.QuarkusEntryPoint.main(QuarkusEntryPoint.java:32)
Caused by: io.smallrye.config.ConfigValidationException: Configuration validation failed:
	java.lang.IllegalArgumentException: SRCFG00039: The config property quarkus.otel.traces.sampler.arg with the config value "endpoint=http://hono-jaeger:14250" threw an Exception whilst being converted SRCFG00031: Expected a double value, got "endpoint=http://hono-jaeger:14250"
	at io.smallrye.config.ConfigMappingProvider.mapConfigurationInternal(ConfigMappingProvider.java:1003)
	at io.smallrye.config.ConfigMappingProvider.lambda$mapConfiguration$3(ConfigMappingProvider.java:959)
	at io.smallrye.config.SecretKeys.doUnlocked(SecretKeys.java:28)
	at io.smallrye.config.ConfigMappingProvider.mapConfiguration(ConfigMappingProvider.java:959)
	at io.smallrye.config.ConfigMappings.mapConfiguration(ConfigMappings.java:91)
	at io.smallrye.config.SmallRyeConfigBuilder.build(SmallRyeConfigBuilder.java:630)
	at io.quarkus.runtime.generated.Config.readConfig(Unknown Source)
	at io.quarkus.deployment.steps.RuntimeConfigSetup.deploy(Unknown Source)
	... 13 more

Expected behavior

quarkus.otel.traces.sampler.arg not being restricted to a double type.

Actual behavior

Setting quarkus.otel.traces.sampler.arg to a String value leads to an exception on startup.

How to Reproduce?

Use a configuration like

quarkus.otel.traces.sampler: "jaeger_remote"
quarkus.otel.traces.sampler.arg: "endpoint=http://hono-jaeger:14250"

Output of uname -a or ver

No response

Output of java -version

No response

GraalVM version (if different from Java)

No response

Quarkus version or git rev

3.2.6

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

No response

Additional information

No response

[quarkus-bot]

/cc @brunobat (jaeger,opentelemetry,tracing), @radcortez (jaeger,opentelemetry,tracing)

[brunobat]

@calohmn, If I understood well, you are using a custom sampler and need the arg to pass a string that can be used inside the custom sampler, right?

[hiteshkhatri97]

@brunobat If anyone else has not yet picked up, can I work on this issue?

[brunobat]

Hi @hiteshkhatri97, sure, you can work on it.