@sentry/astro: Use the Cloudflare Vite plugin for Workers builds #25344

On Cloudflare Workers, an Astro app still needs a hand-written sentry.server.config.js that is also the wrangler main:

// sentry.server.config.js
import * as Sentry from '@sentry/cloudflare';
import handler from '@astrojs/cloudflare/entrypoints/server';
export default Sentry.withSentry(env => ({ dsn: env.E2E_TEST_DSN /* ... */ }), handler);

// wrangler.jsonc
{ "main": "./sentry.server.config.js" }

The goal is the setup that @sentry/cloudflare/vite gives other frameworks: wrangler main stays the package entry, and the options live in an instrument.server.* file beside the wrangler config.

// wrangler.jsonc
{ "main": "@astrojs/cloudflare/entrypoints/server" }

// instrument.server.js
import { defineCloudflareOptions } from '@sentry/cloudflare';
export default defineCloudflareOptions(env => ({ dsn: env.E2E_TEST_DSN /* ... */ }));

@sentry/cloudflare/vite will be able to wrap a package-specifier main as of #24522. The rest of the work is in @sentry/astro.

What blocks it

I tried this setup in the astro-6-cf-workers e2e app, with sentryCloudflareVitePlugin() added to vite.plugins in astro.config.mjs. The Cloudflare plugin wrapped the entry, but 9 of 11 tests failed with Sentry Logger [error]: Transport disabled.

1. Default server init with no DSN. With no sentry.server.config.* file, the integration falls back to buildServerSnippet() (packages/astro/src/integration/snippets.ts). It injects Sentry.init({ dsn: import.meta.env.PUBLIC_SENTRY_DSN, ... }) into every SSR page through injectScript('page-ssr', ...). In this app that builds as dsn: void 0, and this init disables the transport.
2. The integration does not add the Cloudflare plugin. For Workers builds, packages/astro/src/integration/index.ts adds its own sentryCloudflareVitePlugin() from ./cloudflare. That plugin wraps astrojs-ssr-virtual-entry, which @astrojs/cloudflare v13 no longer has, and it always passes () => undefined as the options. The user must add @sentry/cloudflare/vite by hand.
3. Two orchestrion plugins. The integration adds sentryOrchestrionPlugin() for Workers, and @sentry/cloudflare/vite adds another one (with the workerd-safe dcModule). With both, the build-time instrumentation runs twice.

Proposed fix

• For Cloudflare Workers builds, add sentryCloudflareVitePlugin() from @sentry/cloudflare/vite in place of the integration's own Cloudflare and orchestrion plugins.
• Do not inject the default server init snippet on Workers. The withSentry wrap does the init from instrument.server.*, or from env when there is no such file.
• Keep sentry.server.config.* working for apps that still use it as main, because the auto-instrument plugin leaves an entry that is already wrapped alone.
• Update astro-6-cf-workers (and astro-5-cf-workers if it applies): remove sentry.server.config.js, add instrument.server.js with defineCloudflareOptions, and set main to @astrojs/cloudflare/entrypoints/server.

Notes

• @astrojs/cloudflare v13 sets main to @astrojs/cloudflare/entrypoints/server when the wrangler config has none (cloudflareConfigCustomizer in its dist/wrangler.js).
• Its server.js ends with export { server_default as default }. @sentry/cloudflare/vite: Auto-instrumentation skips the Worker when wrangler main is a package specifier #24522 adds support for that export form to the auto-instrument transform.
• Check astro dev too: the integration only adds its Workers plugin when command !== 'dev', and @sentry/cloudflare/vite instruments vite dev as well.