node tracer

index.ts

import { context, trace } from "@opentelemetry/api";
import { AsyncLocalStorageContextManager } from "@opentelemetry/context-async-hooks";
import { BasicTracerProvider, ConsoleSpanExporter, SimpleSpanProcessor } from "@opentelemetry/sdk-trace-base";
import { promisify } from "util";


async function main() {
  const contextManager = new AsyncLocalStorageContextManager();
  const provider = new BasicTracerProvider();
  provider.addSpanProcessor(new SimpleSpanProcessor(new ConsoleSpanExporter()));
  provider.register({ contextManager });

  const tracer = provider.getTracer("example-tracer-node")

  const sleep = promisify(setTimeout);

  const bar = wrapSpan("bar", async (id: string = 'bar') => {
    getActiveSpan()?.setAttribute("id", id);
    console.log('traceId', getActiveSpanContext()?.traceId);
    await sleep(1000);
    return 100;
  });

  startSpan("root", async () => {
    await Promise.all([
      bar('bar1'),
      bar('bar2')
    ]);
  });

  setInterval(() => {
    bar('bar-' + Math.random().toString(36).substring(7));
  }, 2000);


  function getActiveSpan() {
    return trace.getActiveSpan();
  }

  function getActiveSpanContext() {
    return trace.getSpanContext(context.active());
  }

  function wrapSpan<F extends (...args: any[]) => any>(name: string, fn: F): F {
    return ((...args: any[]) => startSpan(name, () => fn(...args))) as F;
  }

  function startSpan<F extends (...args: any[]) => any>(name: string, fn: F): ReturnType<F> {
    return tracer.startActiveSpan(name, (span: any) => {
      try {
        const res = fn();
        return ((res instanceof Promise) ?
          res.finally(() => span.end()) :
          (span.end(), res)) as ReturnType<F>;
      } catch (error) {
        span.end();
        throw error
      }
    });
  }
}

main();