feat(nextjs): Auto-wrap API routes

packages/nextjs/rollup.npm.config.js

@@ -14,7 +14,11 @@ export default [
  ),
  ...makeNPMConfigVariants(
  makeBaseNPMConfig({
- entrypoints: ['src/config/templates/prefixLoaderTemplate.ts', 'src/config/templates/proxyLoaderTemplate.ts'],
+ entrypoints: [
+ 'src/config/templates/prefixLoaderTemplate.ts',
+ 'src/config/templates/pageProxyLoaderTemplate.ts',
+ 'src/config/templates/apiProxyLoaderTemplate.ts',
+ ],
 
  packageSpecificConfig: {
  plugins: [plugins.makeRemoveMultiLineCommentsPlugin()],

packages/nextjs/src/config/loaders/proxyLoader.ts

@@ -33,12 +33,6 @@ export default async function proxyLoader(this: LoaderThis<LoaderOptions>, userC
  // homepage), sub back in the root route
  .replace(/^$/, '/');
 
- // TODO: For the moment we skip API routes. Those will need to be handled slightly differently because of the manual
- // wrapping we've already been having people do using `withSentry`.
- if (parameterizedRoute.startsWith('api')) {
- return userCode;
- }
-
  // We don't want to wrap twice (or infinitely), so in the proxy we add this query string onto references to the
  // wrapped file, so that we know that it's already been processed. (Adding this query string is also necessary to
  // convince webpack that it's a different file than the one it's in the middle of loading now, so that the originals
@@ -47,7 +41,10 @@ export default async function proxyLoader(this: LoaderThis<LoaderOptions>, userC
  return userCode;
  }
 
- const templatePath = path.resolve(__dirname, '../templates/proxyLoaderTemplate.js');
+ const templateFile = parameterizedRoute.startsWith('/api')
+ ? 'apiProxyLoaderTemplate.js'
+ : 'pageProxyLoaderTemplate.js';
+ const templatePath = path.resolve(__dirname, `../templates/${templateFile}`);
  let templateCode = fs.readFileSync(templatePath).toString();
  // Make sure the template is included when runing `webpack watch`
  this.addDependency(templatePath);

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

@@ -0,0 +1,47 @@
+/**
+ * This file is a template for the code which will be substituted when our webpack loader handles API files in the
+ * `pages/` directory.
+ *
+ * We use `__RESOURCE_PATH__` as a placeholder for the path to the file being wrapped. Because it's not a real package,
+ * this causes both TS and ESLint to complain, hence the pragma comments below.
+ */
+
+// @ts-ignore See above
+// eslint-disable-next-line import/no-unresolved
+import * as origModule from '__RESOURCE_PATH__';
+import * as Sentry from '@sentry/nextjs';
+import type { PageConfig } from 'next';
+
+// We import this from `withSentry` rather than directly from `next` because our version can work simultaneously with
+// multiple versions of next. See note in `withSentry` for more.
+import type { NextApiHandler } from '../../utils/withSentry';
+
+type NextApiModule = {
+ default: NextApiHandler;
+ config?: PageConfig;
+};
+
+const userApiModule = origModule as NextApiModule;
+
+const maybeWrappedHandler = userApiModule.default;
+const origConfig = userApiModule.config || {};
+
+// Setting `externalResolver` to `true` prevents nextjs from throwing a warning in dev about API routes resolving
+// without sending a response. It's a false positive (a response is sent, but only after we flush our send queue), and
+// we throw a warning of our own to tell folks that, but it's better if we just don't have to deal with it in the first
+// place.
+export const config = {
+ ...origConfig,
+ api: {
+ ...origConfig.api,
+ externalResolver: true,
+ },
+};
+
+export default Sentry.withSentryAPI(maybeWrappedHandler, '__ROUTE__');
+
+// 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.
+// @ts-ignore See above
+// eslint-disable-next-line import/no-unresolved
+export * from '__RESOURCE_PATH__';

packages/nextjs/src/config/wrappers/index.ts

@@ -4,3 +4,4 @@ export { withSentryServerSideAppGetInitialProps } from './withSentryServerSideAp
 export { withSentryServerSideDocumentGetInitialProps } from './withSentryServerSideDocumentGetInitialProps';
 export { withSentryServerSideErrorGetInitialProps } from './withSentryServerSideErrorGetInitialProps';
 export { withSentryGetServerSideProps } from './withSentryGetServerSideProps';
+export { withSentryAPI } from './withSentryAPI';

packages/nextjs/src/config/wrappers/withSentryAPI.ts

@@ -0,0 +1,39 @@
+import { formatAsCode, nextLogger } from '../../utils/nextLogger';
+// We import these types from `withSentry` rather than directly from `next` because our version can work simultaneously
+// with multiple versions of next. See note in `withSentry` for more.
+import type { NextApiHandler, WrappedNextApiHandler } from '../../utils/withSentry';
+import { withSentry } from '../../utils/withSentry';
+
+/**
+ * Wrap the given API route handler for tracing and error capturing. Thin wrapper around `withSentry`, which only
+ * applies it if it hasn't already been applied.
+ *
+ * @param maybeWrappedHandler The handler exported from the user's API page route file, which may or may not already be
+ * wrapped with `withSentry`
+ * @param parameterizedRoute The page's route, passed in via the proxy loader
+ * @returns The wrapped handler
+ */
+export function withSentryAPI(
+ maybeWrappedHandler: NextApiHandler | WrappedNextApiHandler,
+ parameterizedRoute: string,
+): WrappedNextApiHandler {
+ // Log a warning if the user is still manually wrapping their route in `withSentry`. Doesn't work in cases where
+ // there's been an intermediate wrapper (like `withSentryAPI(someOtherWrapper(withSentry(handler)))`) but should catch
+ // most cases. Only runs once per route. (Note: Such double-wrapping isn't harmful, but we'll eventually deprecate and remove `withSentry`, so
+ // best to get people to stop using it.)
+ if (maybeWrappedHandler.name === 'sentryWrappedHandler') {
+ const [_sentryNextjs_, _autoWrapOption_, _withSentry_, _route_] = [
+ '@sentry/nextjs',
+ 'autoInstrumentServerFunctions',
+ 'withSentry',
+ parameterizedRoute,
+ ].map(phrase => formatAsCode(phrase));
+
+ nextLogger.info(
+ `${_sentryNextjs_} is running with the ${_autoWrapOption_} flag set, which means API routes no longer need to ` +
+ `be manually wrapped with ${_withSentry_}. Detected manual wrapping in ${_route_}.`,
+ );
+ }
+
+ return withSentry(maybeWrappedHandler, parameterizedRoute);
+}

packages/nextjs/src/index.server.ts

@@ -134,6 +134,7 @@ export {
  withSentryServerSideAppGetInitialProps,
  withSentryServerSideDocumentGetInitialProps,
  withSentryServerSideErrorGetInitialProps,
+ withSentryAPI,
 } from './config/wrappers';
 export { withSentry } from './utils/withSentry';
 

packages/nextjs/src/utils/nextLogger.ts

@@ -0,0 +1,31 @@
+/* eslint-disable no-console */
+import * as chalk from 'chalk';
+
+// This is nextjs's own logging formatting, vendored since it's not exported. See
+// https:/vercel/next.js/blob/c3ceeb03abb1b262032bd96457e224497d3bbcef/packages/next/build/output/log.ts#L3-L11
+// and
+// https:/vercel/next.js/blob/de7aa2d6e486c40b8be95a1327639cbed75a8782/packages/next/lib/eslint/runLintCheck.ts#L321-L323.
+
+const prefixes = {
+ wait: `${chalk.cyan('wait')} -`,
+ error: `${chalk.red('error')} -`,
+ warn: `${chalk.yellow('warn')} -`,
+ ready: `${chalk.green('ready')} -`,
+ info: `${chalk.cyan('info')} -`,
+ event: `${chalk.magenta('event')} -`,
+ trace: `${chalk.magenta('trace')} -`,
+};
+
+export const formatAsCode = (str: string): string => chalk.bold.cyan(str);
+
+export const nextLogger: {
+ [key: string]: (...message: unknown[]) => void;
+} = {
+ wait: (...message) => console.log(prefixes.wait, ...message),
+ error: (...message) => console.error(prefixes.error, ...message),
+ warn: (...message) => console.warn(prefixes.warn, ...message),
+ ready: (...message) => console.log(prefixes.ready, ...message),
+ info: (...message) => console.log(prefixes.info, ...message),
+ event: (...message) => console.log(prefixes.event, ...message),
+ trace: (...message) => console.log(prefixes.trace, ...message),
+};

packages/nextjs/src/utils/withSentry.ts

@@ -28,17 +28,32 @@ import { NextApiRequest, NextApiResponse } from 'next';
 // the test app would refer to the other version of the type (from the test app's `node_modules`). By using a custom
 // version of the type compatible with both the old and new official versions, we can use any Next version we want in
 // a test app without worrying about type errors.
-type NextApiHandler = (req: NextApiRequest, res: NextApiResponse) => void | Promise<void> | unknown | Promise<unknown>;
+export type NextApiHandler = (
+ req: NextApiRequest,
+ res: NextApiResponse,
+) => void | Promise<void> | unknown | Promise<unknown>;
 export type WrappedNextApiHandler = (req: NextApiRequest, res: NextApiResponse) => Promise<void> | Promise<unknown>;
 
+type AugmentedNextApiRequest = NextApiRequest & {
+ __withSentry_applied__?: boolean;
+};
+
 export type AugmentedNextApiResponse = NextApiResponse & {
  __sentryTransaction?: Transaction;
 };
 
 // eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
-export const withSentry = (origHandler: NextApiHandler): WrappedNextApiHandler => {
+export const withSentry = (origHandler: NextApiHandler, parameterizedRoute?: string): WrappedNextApiHandler => {
  // eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
- return async (req, res) => {
+ return async function sentryWrappedHandler(req: AugmentedNextApiRequest, res: NextApiResponse) {
+ // We're now auto-wrapping API route handlers using `withSentryAPI` (which uses `withSentry` under the hood), but
+ // users still may have their routes manually wrapped with `withSentry`. This check makes `sentryWrappedHandler`
+ // idempotent so that those cases don't break anything.
+ if (req.__withSentry_applied__) {
+ return origHandler(req, res);
+ }
+ req.__withSentry_applied__ = true;
+
  // first order of business: monkeypatch `res.end()` so that it will wait for us to send events to sentry before it
  // fires (if we don't do this, the lambda will close too early and events will be either delayed or lost)
  // eslint-disable-next-line @typescript-eslint/unbound-method
@@ -69,17 +84,23 @@ export const withSentry = (origHandler: NextApiHandler): WrappedNextApiHandler =
  const baggageHeader = req.headers && req.headers.baggage;
  const dynamicSamplingContext = baggageHeaderToDynamicSamplingContext(baggageHeader);
 
- const url = `${req.url}`;
- // pull off query string, if any
- let reqPath = stripUrlQueryAndFragment(url);
- // Replace with placeholder
- if (req.query) {
- // TODO get this from next if possible, to avoid accidentally replacing non-dynamic parts of the path if
- // they happen to match the values of any of the dynamic parts
- for (const [key, value] of Object.entries(req.query)) {
- reqPath = reqPath.replace(`${value}`, `[${key}]`);
+ // prefer the parameterized route, if we have it (which we will if we've auto-wrapped the route handler)
+ let reqPath = parameterizedRoute;
+
+ // If not, fake it by just replacing parameter values with their names, hoping that none of them match either
+ // each other or any hard-coded parts of the path
+ if (!reqPath) {
+ const url = `${req.url}`;
+ // pull off query string, if any
+ reqPath = stripUrlQueryAndFragment(url);
+ // Replace with placeholder
+ if (req.query) {
+ for (const [key, value] of Object.entries(req.query)) {
+ reqPath = reqPath.replace(`${value}`, `[${key}]`);
+ }
  }
  }
+
  const reqMethod = `${(req.method || 'GET').toUpperCase()} `;
 
  const transaction = startTransaction(

packages/nextjs/test/integration/pages/api/withSentryAPI/unwrapped/[...pathParts].ts

@@ -0,0 +1,7 @@
+import { NextApiRequest, NextApiResponse } from 'next';
+
+const handler = async (_req: NextApiRequest, res: NextApiResponse): Promise<void> => {
+ res.status(200).json({});
+};
+
+export default handler;

packages/nextjs/test/integration/pages/api/withSentryAPI/unwrapped/[animal].ts

@@ -0,0 +1,7 @@
+import { NextApiRequest, NextApiResponse } from 'next';
+
+const handler = async (_req: NextApiRequest, res: NextApiResponse): Promise<void> => {
+ res.status(200).json({});
+};
+
+export default handler;

packages/nextjs/test/integration/pages/api/withSentryAPI/unwrapped/noParams.ts

@@ -0,0 +1,7 @@
+import { NextApiRequest, NextApiResponse } from 'next';
+
+const handler = async (_req: NextApiRequest, res: NextApiResponse): Promise<void> => {
+ res.status(200).json({});
+};
+
+export default handler;

packages/nextjs/test/integration/pages/api/withSentryAPI/wrapped/[...pathParts].ts

@@ -0,0 +1,8 @@
+import { withSentry } from '@sentry/nextjs';
+import { NextApiRequest, NextApiResponse } from 'next';
+
+const handler = async (_req: NextApiRequest, res: NextApiResponse): Promise<void> => {
+ res.status(200).json({});
+};
+
+export default withSentry(handler);

packages/nextjs/test/integration/pages/api/withSentryAPI/wrapped/[animal].ts

@@ -0,0 +1,8 @@
+import { withSentry } from '@sentry/nextjs';
+import { NextApiRequest, NextApiResponse } from 'next';
+
+const handler = async (_req: NextApiRequest, res: NextApiResponse): Promise<void> => {
+ res.status(200).json({});
+};
+
+export default withSentry(handler);

packages/nextjs/test/integration/pages/api/withSentryAPI/wrapped/noParams.ts

@@ -0,0 +1,8 @@
+import { withSentry } from '@sentry/nextjs';
+import { NextApiRequest, NextApiResponse } from 'next';
+
+const handler = async (_req: NextApiRequest, res: NextApiResponse): Promise<void> => {
+ res.status(200).json({});
+};
+
+export default withSentry(handler);

packages/nextjs/test/integration/test/server/tracingWithSentryAPI.js

@@ -0,0 +1,54 @@
+const assert = require('assert');
+
+const { sleep } = require('../utils/common');
+const { getAsync, interceptTracingRequest } = require('../utils/server');
+
+module.exports = async ({ url: urlBase, argv }) => {
+ const urls = {
+ // testName: [url, route]
+ unwrappedNoParamURL: [`/api/withSentryAPI/unwrapped/noParams`, '/api/withSentryAPI/unwrapped/noParams'],
+ unwrappedDynamicURL: [`/api/withSentryAPI/unwrapped/dog`, '/api/withSentryAPI/unwrapped/[animal]'],
+ unwrappedCatchAllURL: [`/api/withSentryAPI/unwrapped/dog/facts`, '/api/withSentryAPI/unwrapped/[...pathParts]'],
+ wrappedNoParamURL: [`/api/withSentryAPI/wrapped/noParams`, '/api/withSentryAPI/wrapped/noParams'],
+ wrappedDynamicURL: [`/api/withSentryAPI/wrapped/dog`, '/api/withSentryAPI/wrapped/[animal]'],
+ wrappedCatchAllURL: [`/api/withSentryAPI/wrapped/dog/facts`, '/api/withSentryAPI/wrapped/[...pathParts]'],
+ };
+
+ const interceptedRequests = {};
+
+ Object.entries(urls).forEach(([testName, [url, route]]) => {
+ interceptedRequests[testName] = interceptTracingRequest(
+ {
+ contexts: {
+ trace: {
+ op: 'http.server',
+ status: 'ok',
+ tags: { 'http.status_code': '200' },
+ },
+ },
+ transaction: `GET ${route}`,
+ type: 'transaction',
+ request: {
+ url: `${urlBase}${url}`,
+ },
+ },
+ argv,
+ testName,
+ );
+ });
+
+ // Wait until all requests have completed
+ await Promise.all(Object.values(urls).map(([url]) => getAsync(`${urlBase}${url}`)));
+
+ await sleep(250);
+
+ const failingTests = Object.entries(interceptedRequests).reduce(
+ (failures, [testName, request]) => (!request.isDone() ? failures.concat(testName) : failures),
+ [],
+ );
+
+ assert.ok(
+ failingTests.length === 0,
+ `Did not intercept transaction request for the following tests: ${failingTests.join(', ')}.`,
+ );
+};