Getting Error Cannot invoke "io.opentelemetry.api.trace.Tracer.spanBuilder(String)" because "this.tracer" is null

[yatamraghu7]

Hi @trask and @laurit,

I am trying to create a new span using the trace Id that we are getting from web socket communication from another micro-service and getting below error

Cannot invoke "io.opentelemetry.api.trace.Tracer.spanBuilder(String)" because "this.tracer" is null

We are using the tracer as below in our code

private Tracer tracer = GlobalOpenTelemetry.getTracer("my-tracer");

Can someone tell us what could be the reason for this and below are the maven dependnecies

                 <dependency>
			<groupId>io.opentelemetry.instrumentation</groupId>
			<artifactId>opentelemetry-spring-boot-starter</artifactId>
			<version>2.7.0</version>
		</dependency>
		<dependency>
			<groupId>io.opentelemetry</groupId>
			<artifactId>opentelemetry-extension-trace-propagators</artifactId>
			<version>1.42.1</version>
		</dependency>
		<dependency>
			<groupId>io.opentelemetry</groupId>
			<artifactId>opentelemetry-api</artifactId>
			<version>1.42.1</version>
		</dependency>

We are trying to achieve the common traceId between the microservices which are communicating using web-socket.
It would be great if we can get some help at this topic.

Problem Can be reproduced using the code here in the repositroy

https://github.com/yatamraghu7/ManualInstrumentationOtel

Thanks

[laurit]

We are using the tracer as below in our code
private Tracer tracer = GlobalOpenTelemetry.getTracer("my-tracer");

But you aren't https://github.com/yatamraghu7/ManualInstrumentationOtel/blob/d8272498d03dc1b2c81cabf8d705b48a415ff2dd/Producer/src/main/java/com/microservice/producer/Producer/Controller/ProducerController.java#L26-L27

[yatamraghu7]

Hi @laurit

Thanks for the update. Do we need to add opentelemetry-sdk dependency to get the tracer ?
I have added that and this sdk is again looking for one more dependency i.e. opentelemetry-api-logs. If I don't add the api-logs I am getting below error

Exception in thread "BatchLogRecordProcessor_WorkerThread-1" java.lang.NoClassDefFoundError: io/opentelemetry/api/incubator/logs/AnyValue

We wanted to avoid this extra dependencies if possible. Is there any way ?

Also as mentioned we are using above provided dependencies which is using 1.42.1 i think the latest but the mvn dependency opentelemetry-api-logs comes with latest version as below

           <dependency>
		<groupId>io.opentelemetry</groupId>
		<artifactId>opentelemetry-api-logs</artifactId>
		<version>1.26.0-alpha</version>
	</dependency>

Our issue is that we are having dependency version mismatch as the 1.26.0-alpha is not compatible with 1.42.1 and for this I have to downgrade to 1.32.0 and with this I have achieved websocket manual tracing.

Can you please tell us that if we can do in a better way with our dependencies.

Thanks

[laurit]

You should not need extra dependencies besides opentelemetry-spring-boot-starter Have a look at https://opentelemetry.io/docs/zero-code/java/spring-boot-starter/getting-started/#dependency-management on how to use a bom to ensure that you get dependencies with correct versions.
Secondly when using spring boot starter there is no implicitly defined Tracer bean, try injecting OpenTelemetry instead. From the injected OpenTelemetry instance you can get a tracer.

[yatamraghu7]

Hi @laurit

Thanks for the explanation. If we are sending a custom X-B3-TraceId and we wanted that traceId to be carried throughout the request flow and we dont want new traceId to be generated and I think injecting OpenTelemetry and getting a tracer from the instance wont change my traceId throughout the request flow right ?

Thanks

[laurit]

no, it won't.

[yatamraghu7]

Thanks @laurit for your support as always.