Export to datadog-agent as span which service name is luna using Deno

run.sh

#!/bin/bash

OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4318 deno run -A sample.ts

sample.ts

// Datadog
import * as opentelemetry from "npm:@opentelemetry/[email protected]"
import {
  SpanKind,
} from "npm:@opentelemetry/[email protected]"
import type {
  Context,
  Span,
  SpanOptions,
} from "npm:@opentelemetry/[email protected]"
import { Resource } from "npm:@opentelemetry/[email protected]"
import {
  ConsoleSpanExporter,
  SimpleSpanProcessor,
} from "npm:@opentelemetry/[email protected]"
import {
  NodeTracerProvider,
  NoopSpanProcessor,
} from "npm:@opentelemetry/[email protected]"
import { registerInstrumentations } from "npm:@opentelemetry/[email protected]"
import { HttpInstrumentation } from "npm:@opentelemetry/[email protected]"
import { FetchInstrumentation } from "npm:@opentelemetry/[email protected]"
import { ExpressInstrumentation } from "npm:@opentelemetry/[email protected]"
import { GraphQLInstrumentation } from "npm:@opentelemetry/[email protected]"
import { OTLPTraceExporter } from "npm:@opentelemetry/[email protected]"
import { SocketIoInstrumentation } from "npm:@opentelemetry/[email protected]"
import { NetInstrumentation } from "npm:@opentelemetry/[email protected]"

// Monkeypatching to get past FetchInstrumentation's dependence on sdk-trace-web, which depends on some browser-only constructs
Object.assign(globalThis, { location: {} }) // released but doesn't work  https://github.com/open-telemetry/opentelemetry-js/blame/6d13eb437932e46e021c840ac5d327d556eb3c52/packages/opentelemetry-sdk-trace-web/src/utils.ts#L315-L319

const OTEL_SDK_DISABLED = false // omit impl: set each of enviromemt
const environment = "LOCAL" // omit impl: show env name from env var

// Initialize provider and identify this particular service
// (in this case, we're implementing a federated gateway)
const provider = new NodeTracerProvider({
  resource: Resource.default().merge(
    new Resource({
      "service.name": "luna",
      "process.runtime.name": "deno",
      "service.instance.id": Deno.hostname(),
      "process.pid": Deno.pid,
      "deployment.environment": environment
    }),
  ),
})

// Workaround: Set NoopSpanProcesor to get the correct behavior.
// https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/#general-sdk-configuration
if (OTEL_SDK_DISABLED) {
  provider.addSpanProcessor(new NoopSpanProcessor())
} else {
  provider.addSpanProcessor(new SimpleSpanProcessor(new OTLPTraceExporter()))
  if (environment === "LOCAL") {
    provider.addSpanProcessor(
      new SimpleSpanProcessor(new ConsoleSpanExporter()),
    )
  }
}

// Register the provider to begin tracing
provider.register()

// Register server-related instrumentation
registerInstrumentations({
  tracerProvider: provider,
  // Sorry, there are not active instrumentations...
  instrumentations: [
    new GraphQLInstrumentation(),
    new HttpInstrumentation(),
    new ExpressInstrumentation(),
    new FetchInstrumentation(),
    new SocketIoInstrumentation(),
    new NetInstrumentation(),
  ],
})

const tracer = opentelemetry.trace.getTracer("luna-tracer-main")
const context = opentelemetry.context.active()

export const startSpan = (
  spanName = "doWork",
  options: SpanOptions = {},
  ctx = context,
): Span =>
  tracer.startSpan(spanName, { kind: SpanKind.SERVER, ...options }, ctx)

const setSpan = (parent: Span): Context =>
  opentelemetry.trace.setSpan(
    opentelemetry.context.active(),
    parent,
  )

export const startSpanWith = (
  parent: Span,
  spanName = "doWork",
  options: SpanOptions = {},
): Span => startSpan(spanName, options, setSpan(parent))

// ----

const parentSpan: Span = startSpan("graphql request")

const child = startSpanWith(parentSpan)
// You do something here
await new Promise(resolve => setTimeout(resolve, 5000));

child.end()