Add API config to allow disabling response size warning

packages/next/server/api-utils/node.ts

@@ -172,6 +172,7 @@ export async function apiResolver(
     }
     const config: PageConfig = resolverModule.config || {}
     const bodyParser = config.api?.bodyParser !== false
+    const bodyLimit = config.api?.bodyLimit ?? true
     const externalResolver = config.api?.externalResolver || false
 
     // Parsing of cookies
@@ -209,9 +210,9 @@ export async function apiResolver(
         contentLength += Buffer.byteLength(args[0] || '')
       }
 
-      if (contentLength >= 4 * 1024 * 1024) {
+      if (bodyLimit && contentLength >= 4 * 1024 * 1024) {
         console.warn(
-          `API response for ${req.url} exceeds 4MB. This will cause the request to fail in a future version. https://nextjs.org/docs/messages/api-routes-body-size-limit`
+          `API response for ${req.url} exceeds 4MB. API Routes are meant to respond quickly. https://nextjs.org/docs/messages/api-routes-body-size-limit`
         )
       }
 

packages/next/types/index.d.ts

@@ -63,6 +63,11 @@ export type NextPage<P = {}, IP = P> = NextComponentType<NextPageContext, IP, P>
 export type PageConfig = {
   amp?: boolean | 'hybrid'
   api?: {
+    /**
+     * Flag to disable warning "API response for ${req.url} exceeds 4MB.",
+     * due to deploying app outside Vercel, like AWS.
+     */
+    bodyLimit?: boolean
     /**
      * The byte limit of the body. This is the number of bytes or any string
      * format supported by `bytes`, for example `1000`, `'500kb'` or `'3mb'`.

test/integration/api-support/pages/api/large-response-with-config.js

@@ -0,0 +1,10 @@
+export const config = {
+  api: {
+    bodyLimit: false,
+  },
+}
+
+export default (req, res) => {
+  let body = '.'.repeat(5 * 1024 * 1024)
+  res.send(body)
+}

test/integration/api-support/test/index.test.js

@@ -451,13 +451,21 @@ function runTests(dev = false) {
     let res = await fetchViaHTTP(appPort, '/api/large-response')
     expect(res.ok).toBeTruthy()
     expect(stderr).toContain(
-      'API response for /api/large-response exceeds 4MB. This will cause the request to fail in a future version.'
+      'API response for /api/large-response exceeds 4MB. API Routes are meant to respond quickly.'
     )
 
     res = await fetchViaHTTP(appPort, '/api/large-chunked-response')
     expect(res.ok).toBeTruthy()
     expect(stderr).toContain(
-      'API response for /api/large-chunked-response exceeds 4MB. This will cause the request to fail in a future version.'
+      'API response for /api/large-chunked-response exceeds 4MB. API Routes are meant to respond quickly.'
+    )
+  })
+
+  it('should not warn if response body is larger than 4MB with config', async () => {
+    let res = await fetchViaHTTP(appPort, '/api/large-response-with-config')
+    expect(res.ok).toBeTruthy()
+    expect(stderr).not.toContain(
+      'API response for /api/large-response-with-config exceeds 4MB. API Routes are meant to respond quickly.'
     )
   })