Cloudflare

Install

In addition to capturing errors, you can monitor interactions between multiple services or applications by enabling tracing.

Select which Sentry features you'd like to install in addition to Error Monitoring to get the corresponding installation and configuration instructions below.

Sentry captures data by using an SDK within your application’s runtime.

npm install @sentry/cloudflare --save

Configure

Configuration should happen as early as possible in your application's lifecycle.

To use the SDK, you'll need to set either the nodejs_compat or nodejs_als compatibility flags in your wrangler.toml. This is because the SDK needs access to the AsyncLocalStorage API to work correctly.

compatibility_flags = ["nodejs_compat"]
# compatibility_flags = ["nodejs_als"]

Then you can install the SDK and add it to your project:

You can either setup up the SDK for Cloudflare Pages or Cloudflare Workers.

Setup (Cloudflare Pages)

To use this SDK, add the sentryPagesPlugin as middleware to your Cloudflare Pages application.

We recommend adding a functions/_middleware.js for the middleware setup so that Sentry is initialized for your entire app.

import * as Sentry from "@sentry/cloudflare";

export const onRequest = [
  // Make sure Sentry is the first middleware
  Sentry.sentryPagesPlugin((context) => ({
    dsn: "https://examplePublicKey@o0.ingest.sentry.io/0",
    // Set tracesSampleRate to 1.0 to capture 100% of spans for tracing.
    // Learn more at
    // https://docs.sentry.io/platforms/javascript/configuration/options/#traces-sample-rate
    tracesSampleRate: 1.0,
  })),
  // Add more middlewares here
];

Setup (Cloudflare Workers)

To use this SDK, wrap your handler with the withSentry function. This will initialize the SDK and hook into the environment. Note that you can turn off almost all side effects using the respective options.

import * as Sentry from '@sentry/cloudflare';

export default withSentry(
  env => ({
    dsn: "https://examplePublicKey@o0.ingest.sentry.io/0",
    // Set tracesSampleRate to 1.0 to capture 100% of spans for tracing.
    // Learn more at
    // https://docs.sentry.io/platforms/javascript/configuration/options/#traces-sample-rate
    tracesSampleRate: 1.0,
  }),
  {
    async fetch(request, env, ctx) {
      return new Response('Hello World!');
    },
  } satisfies ExportedHandler<Env>,
);

Add Readable Stack Traces to Errors

Depending on how you've set up your project, the stack traces in your Sentry errors probably don't look like your actual code.

To fix this, upload your source maps to Sentry.

To start, add upload_source_maps = true to your wrangler.toml file to enable source map uploading.

Then run the Sentry Wizard to finish your set up:

npx @sentry/wizard@latest -i sourcemaps

The wizard will guide you through the following steps:

• Logging into Sentry and selecting a project
• Installing the necessary Sentry packages
• Configuring your build tool to generate and upload source maps
• Configuring your CI to upload source maps

For more information on source maps or for more options to upload them, head over to our Source Maps documentation.

Verify

This snippet includes an intentional error, so you can test that everything is working as soon as you set it up.

Verify your setup by adding the following snippet anywhere in your code and running it:

setTimeout(() => {
  throw new Error();
});

To view and resolve the recorded error, log into sentry.io and select your project. Clicking on the error's title will open a page where you can see detailed information and mark it as resolved.