Runtime instrumentation

With a destination configured, Elide records these without code changes:

Names, units, and attributes are listed in Emitted telemetry.

Serving

Every request served by elide serve, an exported fetch handler, or a node:http server gets a server span and the HTTP server metrics. The handler runs inside the span, so spans your code starts there are its children:

// server.ts
import { trace } from "@opentelemetry/api";

const tracer = trace.getTracer("orders");

export default {
  async fetch(request: Request): Promise<Response> {
    return tracer.startActiveSpan("load order", async (span) => {
      span.setAttribute("order.id", new URL(request.url).searchParams.get("id") ?? "");
      span.end();
      return new Response("ok\n");
    });
  },
};

OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4318 elide serve server.ts

A request carrying a valid traceparent continues the caller’s trace. A 5xx response, a handler that throws, an abandoned response, or a reset connection marks the server span ERROR.

Routes

Server spans are named after the method: GET. A node:http server can name the matched route, which sets http.route and renames the span GET /items/:id:

// routes.ts
import http from "node:http";
import { trace } from "@opentelemetry/api";

http
  .createServer((req, res) => {
    trace.getActiveSpan()?.setAttribute("http.route", "/items/:id");
    res.end("ok\n");
  })
  .listen(8091);

A router that sets req.route (Express and compatible routers) supplies the route without that line; req.baseUrl is prefixed. Inside a node:http handler or an exported fetch handler the active span stands for the server span, and only http.route set on it reaches the exported span.

fetch

Each fetch gets a client span, parented to the span active where fetch was called, and sends traceparent and tracestate so the next service continues the trace. A traceparent header you set yourself is kept.

import { trace } from "@opentelemetry/api";

await trace.getTracer("sync").startActiveSpan("sync inventory", async (span) => {
  await fetch("https://inventory.example.com/items"); // child CLIENT span
  span.end();
});

Process metrics

process.cpu.time, process.memory.usage, process.thread.count, process.unix.file_descriptor.count, and process.uptime, collected at each metric export on Linux and macOS.

Builds and tests in CI

elide build, elide test, and elide install record a root span for the command (elide.build, elide.test, elide.install). Build stages and tasks become child spans with outcome and cache-hit attributes, and each test case becomes a child of elide.test. The root span continues a W3C TRACEPARENT from the environment, so a CI job’s own trace can include the build:

TRACEPARENT=00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01 \
OTEL_EXPORTER_OTLP_ENDPOINT=https://otel.example.com \
elide test

The command span carries elide.ci.* attributes from GitHub Actions, GitLab CI, Buildkite, and CircleCI variables (see Emitted telemetry) and process.exit.code. Elide waits up to 5 seconds for the export before the command returns.

In GitHub Actions:

- name: Test
  run: elide test
  env:
    OTEL_EXPORTER_OTLP_ENDPOINT: ${{ vars.OTEL_ENDPOINT }}
    OTEL_EXPORTER_OTLP_HEADERS: ${{ secrets.OTEL_HEADERS }}
    OTEL_SERVICE_NAME: my-service-ci

Elide’s own logs

Elide’s warnings and errors are exported as log records in the dev.elide.runtime scope, at or above runtime.logs (warn by default), with the active span’s ids. Set runtime { logs = "off" } to stop them.

Not instrumented yet