Express

Add @sentry/node as a dependency:

Copied
npm install --save @sentry/node

Sentry should be initialized as early in your app as possible:

Copied
import express from "express";
import * as Sentry from "@sentry/node";

// or using CommonJS
// const express = require('express');
// const Sentry = require('@sentry/node');

const app = express();

// Sentry must be initialized as early as possible
Sentry.init({
  dsn: "https://examplePublicKey@o0.ingest.sentry.io/0",

  // Add Performance Monitoring by setting tracesSampleRate and adding integration
  // Set tracesSampleRate to 1.0 to capture 100% of transactions
  // We recommend adjusting this value in production
  tracesSampleRate: 1.0,
  integrations: [expressIntegration({ app })],
  // It is possible to specify the routes that should be traced by passing a router instance to the `router` option:
  // expressIntegration({ router: someRouterInstance })
});

// The Sentry request handler middleware must be added before any other handlers
app.use(Sentry.Handlers.requestHandler());
// Performance Monitoring: Create spans and traces for every incoming request
app.use(Sentry.Handlers.tracingHandler());

// All controllers should live here
app.get("/", function rootHandler(req, res) {
  res.end("Hello world!");
});

// The Sentry error handler middleware must be registered before any other error middleware and after all controllers
app.use(Sentry.Handlers.errorHandler());

// Optional fallthrough error handler
app.use(function onError(err, req, res, next) {
  // The ID of error events captured by the Sentry error middleware is attached to `res.sentry`.
  // You can use this ID for debugging, or to correlate requests with errors in Sentry.
  res.statusCode = 500;
  res.end(res.sentry + "\n");
});

app.listen(3000);

You can verify the Sentry integration by creating a route that will throw an error:

Copied
app.get("/debug-sentry", function mainHandler(req, res) {
  throw new Error("My first Sentry error!");
});

requestHandler accepts some options that let you decide what data should be included in the event sent to Sentry.

Possible options are:

Copied
// keys to be extracted from req
request?: boolean | string[]; // default: true = ['cookies', 'data', 'headers', 'method', 'query_string', 'url']

// server name
serverName?: boolean; // default: true

// generate transaction name
//   path == request.path (eg. "/foo")
//   methodPath == request.method + request.path (eg. "GET|/foo")
//   handler == function name (eg. "fooHandler")
transaction?: boolean | 'path' | 'methodPath' | 'handler'; // default: true = 'methodPath'

// keys to be extracted from req.user
user?: boolean | string[]; // default: true = ['id', 'username', 'email']

// client ip address
ip?: boolean; // default: false

// node version
version?: boolean; // default: true

// timeout for fatal route errors to be delivered
flushTimeout?: number; // default: undefined

For example, if you want to skip the server name and add just user, you would use requestHandler like this:

Copied
app.use(
  Sentry.Handlers.requestHandler({
    serverName: false,
    user: ["email"],
  })
);

By default, errorHandler will capture only errors with a status code of 500 or higher. If you want to change it, provide it with the shouldHandleError callback, which accepts middleware errors as its argument and decides, whether an error should be sent or not, by returning an appropriate boolean value.

Copied
app.use(
  Sentry.Handlers.errorHandler({
    shouldHandleError(error) {
      // Capture all 404 and 500 errors
      if (error.status === 404 || error.status === 500) {
        return true;
      }
      return false;
    },
  })
);

You can monitor the performance of your Express application by setting a tracesSampleRate, adding the expressIntegration, and registering the tracingHandler middleware.

Spans are created for the following operations:

  • HTTP requests made with request
  • get calls using native http and https modules
  • Middleware (Express.js only)

When capturing errors locally, ensure that your project's data filter for filtering localhost events is toggled off:

This ensures that errors produced by your browser (such as errors produced by HTTP methods) are properly captured.

Help improve this content
Our documentation is open source and available on GitHub. Your contributions are welcome, whether fixing a typo (drat!) or suggesting an update ("yeah, this would be better").