feat(nextjs): Don't init SDK on Vercel Edge Runtime (#6408)

This PR fixes a problem where we crash out of the box on Vercel and also in production builds when the `experimental-edge` runtime is used in API routes.

We use the fact that Next.js string replaces the global `EdgeRuntime` when a server bundle is supposed to be run on the edge runtime. If this is the case we no-op `Sentry.init` and log a message. We also have to not wrap the API routes automatically in that case.

Tried to add quick tests that test if the API routes still crash. But with our integration test setup it was a pita to get working because this is only really a thing for Next.js 12+.

Author: Luca Forstner

packages/nextjs/src/config/templates/apiProxyLoaderTemplate.ts

@@ -23,7 +23,7 @@ type NextApiModule = (
     }
   // CJS export
   | NextApiHandler
-) & { config?: PageConfig };
+) & { config?: PageConfig & { runtime?: string } };
 
 const userApiModule = origModule as NextApiModule;
 
@@ -53,7 +53,13 @@ export const config = {
   },
 };
 
-export default userProvidedHandler ? Sentry.withSentryAPI(userProvidedHandler, '__ROUTE__') : undefined;
+const isEdgeRuntime = origConfig.runtime === 'experimental-edge';
+
+export default userProvidedHandler
+  ? isEdgeRuntime
+    ? userProvidedHandler
+    : Sentry.withSentryAPI(userProvidedHandler, '__ROUTE__')
+  : undefined;
 
 // Re-export anything exported by the page module we're wrapping. When processing this code, Rollup is smart enough to
 // not include anything whose name matchs something we've explicitly exported above.

packages/nextjs/src/index.client.ts

@@ -2,6 +2,7 @@ import { RewriteFrames } from '@sentry/integrations';
 import { configureScope, init as reactInit, Integrations } from '@sentry/react';
 import { BrowserTracing, defaultRequestInstrumentationOptions, hasTracingEnabled } from '@sentry/tracing';
 import { EventProcessor } from '@sentry/types';
+import { logger } from '@sentry/utils';
 
 import { nextRouterInstrumentation } from './performance/client';
 import { buildMetadata } from './utils/metadata';
@@ -29,10 +30,23 @@ export { BrowserTracing };
 // Treeshakable guard to remove all code related to tracing
 declare const __SENTRY_TRACING__: boolean;
 
+// This is a variable that Next.js will string replace during build with a string if run in an edge runtime from Next.js
+// v12.2.1-canary.3 onwards:
+// https://github.com/vercel/next.js/blob/166e5fb9b92f64c4b5d1f6560a05e2b9778c16fb/packages/next/build/webpack-config.ts#L206
+declare const EdgeRuntime: string | undefined;
+
 type GlobalWithAssetPrefixPath = typeof global & { __rewriteFramesAssetPrefixPath__: string };
 
 /** Inits the Sentry NextJS SDK on the browser with the React SDK. */
 export function init(options: NextjsOptions): void {
+  if (typeof EdgeRuntime === 'string') {
+    // If the SDK is imported when using the Vercel Edge Runtime, it will import the browser SDK, even though it is
+    // running the server part of a Next.js application. We can use the `EdgeRuntime` to check for that case and make
+    // the init call a no-op. This will prevent the SDK from crashing on the Edge Runtime.
+    __DEBUG_BUILD__ && logger.log('Vercel Edge Runtime detected. Will not initialize SDK.');
+    return;
+  }
+
   buildMetadata(options, ['nextjs', 'react']);
   options.environment = options.environment || process.env.NODE_ENV;
   addClientIntegrations(options);

packages/nextjs/src/index.server.ts

@@ -22,6 +22,11 @@ export { ErrorBoundary, showReportDialog, withErrorBoundary } from '@sentry/reac
 type GlobalWithDistDir = typeof global & { __rewriteFramesDistDir__: string };
 const domain = domainModule as typeof domainModule & { active: (domainModule.Domain & Carrier) | null };
 
+// This is a variable that Next.js will string replace during build with a string if run in an edge runtime from Next.js
+// v12.2.1-canary.3 onwards:
+// https://github.com/vercel/next.js/blob/166e5fb9b92f64c4b5d1f6560a05e2b9778c16fb/packages/next/build/webpack-config.ts#L206
+declare const EdgeRuntime: string | undefined;
+
 // Exporting this constant means we can compute it without the linter complaining, even if we stop directly using it in
 // this file. It's important that it be computed as early as possible, because one of its indicators is seeing 'build'
 // (as in the CLI command `next build`) in `process.argv`. Later on in the build process, everything's been spun out
@@ -37,6 +42,11 @@ export function init(options: NextjsOptions): void {
     logger.enable();
   }
 
+  if (typeof EdgeRuntime === 'string') {
+    __DEBUG_BUILD__ && logger.log('Vercel Edge Runtime detected. Will not initialize SDK.');
+    return;
+  }
+
   __DEBUG_BUILD__ && logger.log('Initializing SDK...');
 
   if (sdkAlreadyInitialized()) {