Exclude contextual module references from cleaning dll task

src/dev/build/lib/fs.js

@@ -47,6 +47,17 @@ export function assertAbsolute(path) {
   }
 }
 
+export function isFileAccessible(path) {
+  assertAbsolute(path);
+
+  try {
+    fs.accessSync(path);
+    return true;
+  } catch (e) {
+    return false;
+  }
+}
+
 function longInspect(value) {
   return inspect(value, {
     maxArrayLength: Infinity

src/dev/build/lib/index.js

@@ -31,6 +31,7 @@ export {
   deleteAll,
   deleteEmptyFolders,
   compress,
+  isFileAccessible,
 } from './fs';
 export { scanDelete } from './scan_delete';
 export { scanCopy } from './scan_copy';

src/dev/build/tasks/nodejs_modules/clean_client_modules_on_dll_task.js

@@ -68,13 +68,9 @@ export const CleanClientModulesOnDLLTask = {
 
     // Get dll entries filtering out the ones
     // from any whitelisted module
-    const dllEntries = await getDllEntries(dllManifestPath, whiteListedModules);
+    const dllEntries = await getDllEntries(dllManifestPath, whiteListedModules, baseDir);
 
     for (const relativeEntryPath of dllEntries) {
-      if (relativeEntryPath.includes('@elastic/eui')) {
-        continue;
-      }
-
       const entryPath = `${baseDir}/${relativeEntryPath}`;
 
       // Clean a module included into the dll

src/dev/build/tasks/nodejs_modules/webpack_dll.js

@@ -17,12 +17,17 @@
  * under the License.
  */
 
-import { deleteAll, read, write } from '../../lib';
-import { dirname, sep, relative } from 'path';
+import { deleteAll, isFileAccessible, read, write } from '../../lib';
+import { dirname, sep, relative, resolve } from 'path';
 import pkgUp from 'pkg-up';
 import globby from 'globby';
 
-export async function getDllEntries(manifestPath, whiteListedModules) {
+function checkDllEntryAccess(entry, baseDir = '') {
+  const resolvedPath = baseDir ? resolve(baseDir, entry) : entry;
+  return isFileAccessible(resolvedPath);
+}
+
+export async function getDllEntries(manifestPath, whiteListedModules, baseDir = '') {
   const manifest = JSON.parse(await read(manifestPath));
 
   if (!manifest || !manifest.content) {
@@ -46,7 +51,17 @@ export async function getDllEntries(manifestPath, whiteListedModules) {
     const isWhiteListed = whiteListedModules.some(nonEntry => entry.includes(`node_modules${sep}${nonEntry}${sep}`));
     const isNodeModule = entry.includes('node_modules');
 
-    return !isWhiteListed && isNodeModule;
+    // NOTE: when using dynamic imports on webpack the entry paths could be created
+    // with special context module (ex: lazy recursive) values over directories that are not real files
+    // and only exists in runtime, so we need to check if the entry is a real file.
+    // We found that problem through the issue https://github.com/elastic/kibana/issues/38481
+    //
+    // More info:
+    // https://github.com/webpack/webpack/blob/master/examples/code-splitting-harmony/README.md
+    // https://webpack.js.org/guides/dependency-management/#require-with-expression
+    const isAccessible = checkDllEntryAccess(entry, baseDir);
+
+    return !isWhiteListed && isNodeModule && isAccessible;
   });
 }
 

src/dev/build/tasks/nodejs_modules/webpack_dll.test.js

@@ -17,11 +17,12 @@
  * under the License.
  */
 
-import { read } from '../../lib';
+import { isFileAccessible, read } from '../../lib';
 import { getDllEntries } from './webpack_dll';
 
 jest.mock('../../lib', () => ({
-  read: jest.fn()
+  read: jest.fn(),
+  isFileAccessible: jest.fn(),
 }));
 
 const manifestContentMock = JSON.stringify({
@@ -49,13 +50,29 @@ describe('Webpack DLL Build Tasks Utils', () => {
   it('should get dll entries correctly', async () => {
     read.mockImplementationOnce(async () => manifestContentMock);
 
+    isFileAccessible.mockImplementation(() => true);
+
     const mockManifestPath = '/mock/mock_dll_manifest.json';
     const mockModulesWhitelist = [ 'dep1' ];
     const dllEntries = await getDllEntries(mockManifestPath, mockModulesWhitelist);
 
     expect(dllEntries).toEqual(expect.arrayContaining(['/mock/node_modules/dep2', '/mock/node_modules/dep3']));
   });
 
+  it('should only include accessible files', async () => {
+    read.mockImplementationOnce(async () => manifestContentMock);
+
+    isFileAccessible.mockImplementation(() => false);
+
+    const mockManifestPath = '/mock/mock_dll_manifest.json';
+    const mockModulesWhitelist = [ 'dep1' ];
+    const dllEntries = await getDllEntries(mockManifestPath, mockModulesWhitelist);
+
+    isFileAccessible.mockRestore();
+
+    expect(dllEntries.length).toEqual(0);
+  });
+
   it('should throw an error for no manifest file', async () => {
     read.mockImplementationOnce(async () => noManifestMock);