Add asset relocator for production mode of serverless trace

packages/next/build/webpack-config.ts

@@ -83,6 +83,8 @@ export default async function getBaseWebpackConfig(
   const isServerlessTrace = target === 'experimental-serverless-trace'
   const isLikeServerless = isServerless || isServerlessTrace
 
+  const isProductionServerlessTrace = isServerlessTrace && !dev && isServer
+
   const outputDir = isLikeServerless ? SERVERLESS_DIRECTORY : SERVER_DIRECTORY
   const outputPath = path.join(distDir, isServer ? outputDir : '')
   const totalPages = Object.keys(entrypoints).length
@@ -403,10 +405,40 @@ export default async function getBaseWebpackConfig(
         ...nodePathList, // Support for NODE_PATH environment variable
       ],
     },
+    ...(isProductionServerlessTrace
+      ? {
+          // `@zeit/webpack-asset-relocator-loader` will relocated all assets
+          // so we can't let webpack mock this to `/` & `/index.js`.
+          //
+          // This is not enabled for `target: 'serverless'` for backwards
+          // compatibility reasons.
+          node: { __dirname: false, __filename: false },
+        }
+      : undefined),
     // @ts-ignore this is filtered
     module: {
       strictExportPresence: true,
       rules: [
+        // This loader relocates all build assets into a new folder since we
+        // change the emitted path structure during bundling.
+        //
+        // This is not enabled for `target: 'serverless'` for backwards
+        // compatibility reasons.
+        isProductionServerlessTrace && {
+          // These extensions have been transformed into traditional JavaScript
+          // by prior loaders.
+          test: /\.(tsx|ts|js|mjs|jsx|node)$/,
+          parser: { amd: false },
+          use: {
+            loader: '@zeit/webpack-asset-relocator-loader',
+            options: {
+              outputAssetBase: 'assets',
+              existingAssetNames: [],
+              wrapperCompatibility: false,
+              production: true,
+            },
+          },
+        },
         (selectivePageBuilding || config.experimental.terserLoader) &&
           !isServer && {
             test: /\.(js|mjs|jsx)$/,

packages/next/package.json

@@ -67,6 +67,7 @@
     "@babel/preset-typescript": "7.3.3",
     "@babel/runtime": "7.4.5",
     "@babel/runtime-corejs2": "7.4.5",
+    "@zeit/webpack-asset-relocator-loader": "0.6.2",
     "amphtml-validator": "1.0.23",
     "async-sema": "3.0.0",
     "autodll-webpack-plugin": "0.4.2",

yarn.lock

@@ -2342,6 +2342,13 @@
   dependencies:
     "@babel/preset-typescript" "^7.0.0"
 
+"@zeit/[email protected]":
+  version "0.6.2"
+  resolved "https://registry.yarnpkg.com/@zeit/webpack-asset-relocator-loader/-/webpack-asset-relocator-loader-0.6.2.tgz#b15353d8578562f299eddb94d4b771297acc0487"
+  integrity sha512-IUz2YvFAv03LHP4dhjHqG549ecZhdp7KU8B+vGfJRgcDzvlCmc9CA1YcYfJHVO96U8dU5z85RIysr2whYUXmgQ==
+  dependencies:
+    sourcemap-codec "^1.4.4"
+
 JSONStream@^1.0.4, JSONStream@^1.3.4:
   version "1.3.5"
   resolved "https://registry.yarnpkg.com/JSONStream/-/JSONStream-1.3.5.tgz#3208c1f08d3a4d99261ab64f92302bc15e111ca0"
@@ -12241,6 +12248,11 @@ source-map@^0.5.0, source-map@^0.5.3, source-map@^0.5.6:
   resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.5.7.tgz#8a039d2d1021d22d1ea14c80d8ea468ba2ef3fcc"
   integrity sha1-igOdLRAh0i0eoUyA2OpGi6LvP8w=
 
+sourcemap-codec@^1.4.4:
+  version "1.4.6"
+  resolved "https://registry.yarnpkg.com/sourcemap-codec/-/sourcemap-codec-1.4.6.tgz#e30a74f0402bad09807640d39e971090a08ce1e9"
+  integrity sha512-1ZooVLYFxC448piVLBbtOxFcXwnymH9oUF8nRd3CuYDVvkRBxRl6pB4Mtas5a4drtL+E8LDgFkQNcgIw6tc8Hg==
+
 spawn-sync@^1.0.15:
   version "1.0.15"
   resolved "https://registry.yarnpkg.com/spawn-sync/-/spawn-sync-1.0.15.tgz#b00799557eb7fb0c8376c29d44e8a1ea67e57476"