Replace traceId with a manual traceId from header in Span in Opentelemetry Context JS

[allanh1193cr]

Hello community. I'm new with OTel and I would like to ask you something:
I'm using OpenTelemetry to distribute tracing in some microservices I have builded in Java. Those services are exposed in an ApiGateway in AWS. The APIGateway has a proxy for each microservice. I have created an implementation to forward the information using OpenTelemetry and send it to StopLight. I'm able to see the information in StopLight and X-Ray using the trace-Id which is generated automatically by the API. Now I want to have the possibility to send a custom trace-Id in the header of my request and modify the current trace-id by my trace-id. I modified the main span with the custom trace-id but it does not being replicated to the other spans(children) This is how my code looks:

/* eslint-disable no-param-reassign */
const { context: otelContext, propagation, trace } = require('@opentelemetry/api');

global.configureLambdaInstrumentation = (config) => {
  return {
    ...config,
    requestHook: (span, { event, context }) => {
      // adds an attribute to the span in the requestHook
      // span.setAttribute("custom.req", "my request hook");
      // renames the span to 'handler'
      span.updateName(`${context.functionName} handler`);
    },
    responseHook: (span, { err, res }) => {
      span.setAttribute('otlp.trace_id', 'otlpTESTTraceIdAllan');
      // captures the error message as an attribute when the function errors
      if (err instanceof Error) span.setAttribute('faas.error', err.message);
      if (res) {
        // adds the response from the function as a span event
        span.addEvent('Result', res);
      }
      // adds an attribute to the span in the responseHook
      // span.setAttribute("custom.resp", "my response hook attr");
    },
    // disable propagation using AWS X-Ray headers
    disableAwsContextPropagation: true,
    // define how to extract context from the Lambda event
    eventContextExtractor: (event, context) => {

      if(event && event.headers) {
        return trace.setSpanContext(otelContext.active(), {
          traceId: event.headers['traceId'],
          'otlp.traceId': event.headers['traceId'],
          isRemote: true,
        });
      }

      // there are different ways to do this but here
      // we are using the HTTP headers format but setting
      // the trace ID to the appropriate context value from
      // the event object
      let carrier = {};
      // if the request comes from APIGW the HTTP headers
      // will be added to the headers property on the event
      if (event.headers) {
        carrier = event.headers;
        carrier.traceId = event.headers['Transaction-Ref-Id'];
      }

      // if the request is a Lambda.Invoke() from the SDK
      // the context will be in Custom property of the
      // ClientContext on the Lambda context object
      if (context.clientContext && context.clientContext.Custom) {
        carrier = context.clientContext.Custom;
      }
      let currentContext = otelContext.active();
      const span = trace.getSpan(currentContext);
      span.setAttribute('otlp.traceId', 'otlpTESTINGSPAN');
      span.setAttribute('traceId', 'traceIdTESTINGSPAN');
      trace.setSpanContext(span);

      let baggage =
        propagation.getBaggage(currentContext) || propagation.createBaggage();
      baggage = baggage.setEntry('testingBaggage', { value: 'testBaggage123' });
      currentContext = propagation.setBaggage(currentContext, baggage);
      // use the the propagation.extract() method and a custom
      // getter/setter to update the active context with the
      // values you values you defined above
      return propagation.extract(currentContext, carrier);
    },
  };
};

I have read about baggage propagation but I don't understand clearly how it works.

Thanks in advance!!