From 67a27774ac9e0aa906797fa3a02cccec40d71fcb Mon Sep 17 00:00:00 2001
From: Colum Ferry <cferry09@gmail.com>
Date: Thu, 9 Jun 2022 10:16:57 +0100
Subject: [PATCH] fix(angular): support secondary entry points #10329 (#10615)

---
 e2e/angular-core/src/projects.test.ts         | 18 ++++-
 packages/angular/src/utils/mfe/mfe-webpack.ts | 70 +++++++++++++++++++
 2 files changed, 85 insertions(+), 3 deletions(-)

diff --git a/e2e/angular-core/src/projects.test.ts b/e2e/angular-core/src/projects.test.ts
index 17649e6e37bb8..a1e3aec1ea18a 100644
--- a/e2e/angular-core/src/projects.test.ts
+++ b/e2e/angular-core/src/projects.test.ts
@@ -222,13 +222,14 @@ describe('Angular Projects', () => {
     expect(buildOutput).toContain('Successfully ran target build');
   });
 
-  it('MFE - should serve the host and remote apps successfully, even with a shared library between them', async () => {
+  it('MFE - should serve the host and remote apps successfully, even with a shared library with a secondary entry point between them', async () => {
     // ACT + ASSERT
     const port1 = 4200;
     const port2 = 4206;
     const hostApp = uniq('app');
     const remoteApp1 = uniq('remote');
-    const sharedLib = uniq('sharedLib');
+    const sharedLib = uniq('shared-lib');
+    const secondaryEntry = uniq('secondary');
 
     // generate host app
     runCLI(
@@ -241,7 +242,12 @@ describe('Angular Projects', () => {
     );
 
     // generate a shared lib
-    runCLI(`generate @nrwl/angular:library ${sharedLib} --no-interactive`);
+    runCLI(
+      `generate @nrwl/angular:library ${sharedLib} --buildable --no-interactive`
+    );
+    runCLI(
+      `generate @nrwl/angular:library-secondary-entry-point --library=${sharedLib} --name=${secondaryEntry} --no-interactive`
+    );
 
     // update the files to use shared library
     updateFile(
@@ -251,6 +257,9 @@ describe('Angular Projects', () => {
       import { ${
         names(sharedLib).className
       }Module } from '@${proj}/${sharedLib}';
+      import { ${
+        names(secondaryEntry).className
+      }Module } from '@${proj}/${secondaryEntry}';
       import { AppComponent } from './app.component';
       import { NxWelcomeComponent } from './nx-welcome.component';
       import { RouterModule } from '@angular/router';
@@ -285,6 +294,9 @@ describe('Angular Projects', () => {
     import { CommonModule } from '@angular/common';
     import { RouterModule } from '@angular/router';
     import { ${names(sharedLib).className}Module } from '@${proj}/${sharedLib}';
+      import { ${
+        names(secondaryEntry).className
+      }Module } from '@${proj}/${secondaryEntry}';
     import { RemoteEntryComponent } from './entry.component';
     
     @NgModule({
diff --git a/packages/angular/src/utils/mfe/mfe-webpack.ts b/packages/angular/src/utils/mfe/mfe-webpack.ts
index 46598b6868cfc..5dcacd41b6fc8 100644
--- a/packages/angular/src/utils/mfe/mfe-webpack.ts
+++ b/packages/angular/src/utils/mfe/mfe-webpack.ts
@@ -22,6 +22,65 @@ export interface SharedLibraryConfig {
   eager?: boolean;
 }
 
+function traverseUpFileTreeAndPerformActionUntil(
+  dirPath: string,
+  endPath: string,
+  action: (dirname: string) => boolean
+) {
+  while (dirPath !== endPath) {
+    if (action(dirPath)) {
+      break;
+    }
+    dirPath = dirname(dirPath);
+  }
+}
+
+function collectWorkspaceLibrarySecondaryEntryPoints(
+  library: string,
+  libraryPath: string,
+  tsconfigPathAliases: Record<string, string[]>
+) {
+  let libraryRootDirPath = libraryPath;
+  traverseUpFileTreeAndPerformActionUntil(
+    dirname(libraryRootDirPath),
+    workspaceRoot,
+    (currentDirPath) => {
+      if (existsSync(join(currentDirPath, 'package.json'))) {
+        libraryRootDirPath = currentDirPath;
+        return true;
+      }
+    }
+  );
+
+  const aliasesUnderLibrary = Object.keys(tsconfigPathAliases).filter(
+    (libName) => libName.startsWith(library) && libName !== library
+  );
+  const secondaryEntryPoints = [];
+  for (const alias of aliasesUnderLibrary) {
+    const pathToLib = dirname(
+      join(workspaceRoot, tsconfigPathAliases[alias][0])
+    );
+    let isSecondaryEntrypoint = false;
+    let searchDir = pathToLib;
+    traverseUpFileTreeAndPerformActionUntil(
+      searchDir,
+      libraryRootDirPath,
+      (currentDirPath) => {
+        if (existsSync(join(currentDirPath, 'ng-package.json'))) {
+          isSecondaryEntrypoint = true;
+          return true;
+        }
+      }
+    );
+
+    if (isSecondaryEntrypoint) {
+      secondaryEntryPoints.push({ name: alias, path: pathToLib });
+    }
+  }
+
+  return secondaryEntryPoints;
+}
+
 export function shareWorkspaceLibraries(
   libraries: string[],
   tsConfigPath = process.env.NX_TSCONFIG_PATH ?? getRootTsConfigPath()
@@ -48,6 +107,17 @@ export function shareWorkspaceLibraries(
   for (const [key, paths] of Object.entries(tsconfigPathAliases)) {
     if (libraries && libraries.includes(key)) {
       const pathToLib = normalize(join(workspaceRoot, paths[0]));
+      collectWorkspaceLibrarySecondaryEntryPoints(
+        key,
+        pathToLib,
+        tsconfigPathAliases
+      ).forEach(({ name, path }) =>
+        pathMappings.push({
+          name,
+          path,
+        })
+      );
+
       pathMappings.push({
         name: key,
         path: pathToLib,