feat(angular): add flag to include hydration when setting up ssr (#18675)

docs/generated/packages/angular/generators/setup-ssr.json

@@ -53,6 +53,10 @@
         "type": "boolean",
         "description": "Use Standalone Components to bootstrap SSR. _Note: This is only supported in Angular versions >= 14.1.0_."
       },
+      "hydration": {
+        "type": "boolean",
+        "description": "Set up Hydration for the SSR application. _Note: This is only supported in Angular versions >= 16.0.0_."
+      },
       "skipFormat": {
         "type": "boolean",
         "description": "Skip formatting the workspace after the generator completes.",

packages/angular/src/generators/setup-ssr/lib/add-hydration.ts

@@ -0,0 +1,73 @@
+import {
+  joinPathFragments,
+  readProjectConfiguration,
+  type Tree,
+} from '@nx/devkit';
+import { type Schema } from '../schema';
+import {
+  addProviderToAppConfig,
+  addProviderToModule,
+} from '../../../utils/nx-devkit/ast-utils';
+import { ensureTypescript } from '@nx/js/src/utils/typescript/ensure-typescript';
+import { SourceFile } from 'typescript';
+import { insertImport } from '@nx/js';
+
+let tsModule: typeof import('typescript');
+
+export function addHydration(tree: Tree, options: Schema) {
+  const projectConfig = readProjectConfiguration(tree, options.project);
+
+  if (!tsModule) {
+    tsModule = ensureTypescript();
+  }
+  const addImport = (
+    source: SourceFile,
+    symbolName: string,
+    packageName: string,
+    filePath: string,
+    isDefault = false
+  ): SourceFile => {
+    return insertImport(
+      tree,
+      source,
+      filePath,
+      symbolName,
+      packageName,
+      isDefault
+    );
+  };
+
+  const pathToClientConfigFile = options.standalone
+    ? joinPathFragments(projectConfig.sourceRoot, 'app/app.config.ts')
+    : joinPathFragments(projectConfig.sourceRoot, 'app/app.module.ts');
+
+  const sourceText = tree.read(pathToClientConfigFile, 'utf-8');
+  let sourceFile = tsModule.createSourceFile(
+    pathToClientConfigFile,
+    sourceText,
+    tsModule.ScriptTarget.Latest,
+    true
+  );
+
+  sourceFile = addImport(
+    sourceFile,
+    'provideClientHydration',
+    '@angular/platform-browser',
+    pathToClientConfigFile
+  );
+
+  if (options.standalone) {
+    addProviderToAppConfig(
+      tree,
+      pathToClientConfigFile,
+      'provideClientHydration()'
+    );
+  } else {
+    addProviderToModule(
+      tree,
+      sourceFile,
+      pathToClientConfigFile,
+      'provideClientHydration()'
+    );
+  }
+}

packages/angular/src/generators/setup-ssr/lib/index.ts

@@ -3,3 +3,4 @@ export * from './normalize-options';
 export * from './update-app-module';
 export * from './update-project-config';
 export * from './validate-options';
+export * from './add-hydration';

packages/angular/src/generators/setup-ssr/lib/normalize-options.ts

@@ -15,5 +15,6 @@ export function normalizeOptions(tree: Tree, options: Schema) {
     rootModuleClassName: options.rootModuleClassName ?? 'AppServerModule',
     skipFormat: options.skipFormat ?? false,
     standalone: options.standalone ?? isStandaloneApp,
+    hydration: options.hydration ?? false,
   };
 }

packages/angular/src/generators/setup-ssr/lib/validate-options.ts

@@ -1,11 +1,28 @@
 import type { Tree } from '@nx/devkit';
+import { stripIndents } from '@nx/devkit';
 import {
   validateProject,
   validateStandaloneOption,
 } from '../../utils/validations';
 import type { Schema } from '../schema';
+import { getInstalledAngularVersionInfo } from '../../utils/version-utils';
+import { lt } from 'semver';
 
 export function validateOptions(tree: Tree, options: Schema): void {
   validateProject(tree, options.project);
   validateStandaloneOption(tree, options.standalone);
+  validateHydrationOption(tree, options.hydration);
+}
+
+function validateHydrationOption(tree: Tree, hydration: boolean): void {
+  if (!hydration) {
+    return;
+  }
+
+  const installedAngularVersion = getInstalledAngularVersionInfo(tree).version;
+
+  if (lt(installedAngularVersion, '16.0.0')) {
+    throw new Error(stripIndents`The "hydration" option is only supported in Angular >= 16.0.0. You are currently using "${installedAngularVersion}".
+    You can resolve this error by removing the "hydration" option or by migrating to Angular 16.0.0.`);
+  }
 }

packages/angular/src/generators/setup-ssr/schema.d.ts

@@ -7,5 +7,6 @@ export interface Schema {
   rootModuleFileName?: string;
   rootModuleClassName?: string;
   standalone?: boolean;
+  hydration?: boolean;
   skipFormat?: boolean;
 }

packages/angular/src/generators/setup-ssr/schema.json

@@ -53,6 +53,10 @@
       "type": "boolean",
       "description": "Use Standalone Components to bootstrap SSR. _Note: This is only supported in Angular versions >= 14.1.0_."
     },
+    "hydration": {
+      "type": "boolean",
+      "description": "Set up Hydration for the SSR application. _Note: This is only supported in Angular versions >= 16.0.0_."
+    },
     "skipFormat": {
       "type": "boolean",
       "description": "Skip formatting the workspace after the generator completes.",

packages/angular/src/generators/setup-ssr/setup-ssr.spec.ts

@@ -237,6 +237,78 @@ describe('setupSSR', () => {
     `);
   });
 
+  it('should add hydration correctly for NgModule apps', async () => {
+    // ARRANGE
+    const tree = createTreeWithEmptyWorkspace({ layout: 'apps-libs' });
+
+    await generateTestApplication(tree, {
+      name: 'app1',
+    });
+
+    // ACT
+    await setupSsr(tree, { project: 'app1', hydration: true });
+
+    // ASSERT
+    expect(tree.read('apps/app1/src/app/app.module.ts', 'utf-8'))
+      .toMatchInlineSnapshot(`
+      "import { NgModule } from '@angular/core';
+      import {
+        BrowserModule,
+        provideClientHydration,
+      } from '@angular/platform-browser';
+      import { AppComponent } from './app.component';
+      import { NxWelcomeComponent } from './nx-welcome.component';
+
+      @NgModule({
+        declarations: [AppComponent, NxWelcomeComponent],
+        imports: [BrowserModule],
+        providers: [provideClientHydration()],
+        bootstrap: [AppComponent],
+      })
+      export class AppModule {}
+      "
+    `);
+  });
+
+  it('should add hydration correctly to standalone', async () => {
+    // ARRANGE
+    const tree = createTreeWithEmptyWorkspace({ layout: 'apps-libs' });
+
+    await generateTestApplication(tree, {
+      name: 'app1',
+      standalone: true,
+    });
+
+    // ACT
+    await setupSsr(tree, { project: 'app1', hydration: true });
+
+    // ASSERT
+    expect(tree.read('apps/app1/src/app/app.config.ts', 'utf-8'))
+      .toMatchInlineSnapshot(`
+      "import { ApplicationConfig } from '@angular/core';
+      import { provideClientHydration } from '@angular/platform-browser';
+
+      export const appConfig: ApplicationConfig = {
+        providers: [provideClientHydration()],
+      };
+      "
+    `);
+
+    expect(tree.read('apps/app1/src/app/app.config.server.ts', 'utf-8'))
+      .toMatchInlineSnapshot(`
+      "import { mergeApplicationConfig, ApplicationConfig } from '@angular/core';
+      import { provideServerRendering } from '@angular/platform-server';
+      import { appConfig } from './app.config';
+
+      const serverConfig: ApplicationConfig = {
+        providers: [provideServerRendering()],
+      };
+
+      export const config = mergeApplicationConfig(appConfig, serverConfig);
+      "
+    `);
+  });
+
   describe('compat', () => {
     it('should install the correct versions when using older versions of Angular', async () => {
       // ARRANGE

packages/angular/src/generators/setup-ssr/setup-ssr.ts

@@ -4,8 +4,12 @@ import {
   formatFiles,
   installPackagesTask,
 } from '@nx/devkit';
-import { versions } from '../utils/version-utils';
 import {
+  getInstalledPackageVersionInfo,
+  versions,
+} from '../utils/version-utils';
+import {
+  addHydration,
   generateSSRFiles,
   normalizeOptions,
   updateAppModule,
@@ -25,16 +29,26 @@ export async function setupSsr(tree: Tree, schema: Schema) {
     updateAppModule(tree, options);
   }
 
+  if (options.hydration) {
+    addHydration(tree, options);
+  }
+
   const pkgVersions = versions(tree);
 
   addDependenciesToPackageJson(
     tree,
     {
-      '@nguniversal/express-engine': pkgVersions.ngUniversalVersion,
+      '@nguniversal/express-engine':
-      '@angular/platform-server': pkgVersions.angularVersion,
+        getInstalledPackageVersionInfo(tree, '@nguniversal/express-engine')
+          ?.version ?? pkgVersions.ngUniversalVersion,
+      '@angular/platform-server':
+        getInstalledPackageVersionInfo(tree, '@angular/platform-server')
+          ?.version ?? pkgVersions.angularVersion,
     },
     {
-      '@nguniversal/builders': pkgVersions.ngUniversalVersion,
+      '@nguniversal/builders':
+        getInstalledPackageVersionInfo(tree, '@nguniversal/builders')
+          ?.version ?? pkgVersions.ngUniversalVersion,
     }
   );