@logfrog/node

Request tracing middleware for LogFrog. Records every HTTP request your API serves — method, route, status, duration, client IP — and ships it in batches to your LogFrog Traces dashboard.

Supports Express (v4/v5) and Fastify (v4/v5). Zero runtime dependencies; uses the built-in fetch (Node 18+).

Install

npm install @logfrog/node

Express

import express from "express";
import { logfrogExpressMiddleware } from "@logfrog/node/express";

const app = express();

app.use(logfrogExpressMiddleware({
  ingestUrl: "https://api.logfrog.io/api/ingest/traces/<your-token>",
  service: "my-api",
}));

// …your routes

Your ingest URL (with the project token baked in) is on the Traces page of your LogFrog dashboard.

Fastify

import Fastify from "fastify";
import { registerLogfrogFastify } from "@logfrog/node/fastify";

const app = Fastify();

registerLogfrogFastify(app, {
  ingestUrl: "https://api.logfrog.io/api/ingest/traces/<your-token>",
  service: "my-api",
});

// …your routes

registerLogfrogFastify returns the underlying tracer and automatically flushes pending spans when the Fastify instance closes.

Options

Both middlewares accept:

| option | type | description | | --- | --- | --- | | ingestUrl | string (required) | Your project's trace ingest URL from the dashboard. | | service | string | Service name shown in the Traces UI. | | ignore | (req) => boolean | Return true to skip recording a request (e.g. health checks). | | routeResolver | (req) => string \| undefined | Express only — override route template detection. |

Spans are batched (25 per POST) and flushed every 2 seconds. Failed batches are retried on the next flush with a bounded queue, so LogFrog outages never back-pressure your API.

Custom spans

For anything that isn't Express/Fastify, use the tracer directly:

import { createLogfrogTracer } from "@logfrog/node";

const tracer = createLogfrogTracer({
  ingestUrl: "https://api.logfrog.io/api/ingest/traces/<your-token>",
  service: "worker",
});

tracer.record({
  method: "POST",
  path: "/jobs/resize-image",
  status_code: 200,
  duration_ms: 132,
  timestamp: Date.now(),
});

// on shutdown
await tracer.flush();
tracer.stop();

License

MIT