MyOTELTrace.ts

class MyTrace {
  private spanMap = new Map<string, Span>();
  private readonly tracerName = 'my_tracer';

  constructor(private otel: OTELApi) {}
  
  createSingleRunSpan(spanName: string) {
    const span = this.otel.trace.getTracer(this.tracerName).startSpan(spanName);
    const end = () => span.end();
    return { span, end };
  }
  
  createRootSpan(spanName: string) {
    if (this.spanMap.has(spanName)) {
      throw new Error(`Span with name ${spanName} already exists`);
    }
    const span = this.otel.trace.getTracer(this.tracerName).startSpan(spanName);
    this.spanMap.set(spanName, span);
    return span;
  }

  createChildSpan(spanName: string, parentSpanName: string) {
    if (this.spanMap.has(spanName)) {
      throw new Error(`[Span] Span with name ${spanName} already exists`);
    }
    if (!this.spanMap.has(parentSpanName)) {
      throw new Error(
        `[Parent Span] Span with name ${parentSpanName} does not exist`
      );
    }

    const context = this.otel.trace.setSpan(
      this.otel.context.active(),
      this.spanMap.get(parentSpanName)!
    );
    const span = this.otel.trace
      .getTracer(this.tracerName)
      .startSpan(spanName, {}, context);

    this.spanMap.set(spanName, span);
    return span;
  }

  endSpan(spanName: string) {
    if (!this.spanMap.has(spanName)) {
      throw new Error(`Span with name ${spanName} does not exist`);
    }
    const span = this.spanMap.get(spanName);
    span!.end();
  }
}