CCDM: support @Push annotation

Fixes #6972

flow-client/src/main/resources/META-INF/resources/frontend/Flow.ts

@@ -3,14 +3,15 @@ export interface FlowConfig {
 }
 
 interface AppConfig {
-  productionMode: boolean,
-  appId: string,
-  uidl: object,
-  webComponentMode: boolean
+  productionMode: boolean;
+  appId: string;
+  uidl: object;
+  webComponentMode: boolean;
 }
 
 interface AppInitResponse {
   appConfig: AppConfig;
+  pushScript?: string;
 }
 
 interface HTMLRouterContainer extends HTMLElement {
@@ -178,13 +179,20 @@ export class Flow {
       // Enable or disable server side routing
       this.response.appConfig.webComponentMode = !serverSideRouting;
 
+      const {pushScript, appConfig} = this.response;
+
+      if (typeof pushScript === 'string') {
+        await this.loadScript(pushScript);
+      }
+      const {appId} = appConfig;
+
       // Load bootstrap script with server side parameters
       const bootstrapMod = await import('./FlowBootstrap');
       await bootstrapMod.init(this.response);
 
       // Load custom modules defined by user
       if (typeof this.config.imports === 'function') {
-        this.injectAppIdScript(this.response);
+        this.injectAppIdScript(appId);
         await this.config.imports();
       }
 
@@ -194,11 +202,10 @@ export class Flow {
 
       // When client-side router, create a container for server views
       if (!serverSideRouting) {
-        const id = this.response.appConfig.appId;
         // we use a custom tag for the flow app container
-        const tag = `flow-container-${id.toLowerCase()}`;
-        this.container = this.flowRoot.$[id] = document.createElement(tag);
-        this.container.id = id;
+        const tag = `flow-container-${appId.toLowerCase()}`;
+        this.container = this.flowRoot.$[appId] = document.createElement(tag);
+        this.container.id = appId;
 
         // It might be that components created from server expect that their content has been rendered.
         // Appending eagerly the container we avoid these kind of errors.
@@ -210,8 +217,17 @@ export class Flow {
     return this.response;
   }
 
-  private injectAppIdScript(response: AppInitResponse) {
-    const appId = response.appConfig.appId;
+  private async loadScript(url: string): Promise<void> {
+    return new Promise((resolve, reject) => {
+      const script = document.createElement('script');
+      script.onload = () => resolve();
+      script.onerror = reject;
+      script.src = url;
+      document.body.appendChild(script);
+    });
+  }
+
+  private injectAppIdScript(appId: string) {
     const appIdWithoutHashCode = appId.substring(0, appId.lastIndexOf('-'));
     const scriptAppId = document.createElement('script');
     scriptAppId.type = 'module';

flow-server/src/main/java/com/vaadin/flow/component/page/AppShellConfigurator.java

@@ -34,8 +34,10 @@
  * <li>{@link Viewport}: defines the viewport tag of the page</li>
  * <li>{@link BodySize}: configures the size of the body</li>
  * <li>{@link PageTitle}: establishes the page title</li>
- * <li>{@link PWA}: Defines application PWA properties</li>
+ * <li>{@link Push}: configures automatic server push</li>
+ * <li>{@link PWA}: defines application PWA properties</li>
  * </ul>
+ *
  * <p>
  * There is a single application shell for the entire Vaadin application, and
  * therefore there can be at max one class implementing {@link AppShellConfigurator}.
@@ -55,6 +57,7 @@
  * &#64;Viewport("width=device-width, initial-scale=1")
  * &#64;BodySize(height = "100vh", width = "100vw")
  * &#64;PageTitle("my-title")
+ * &#67;Push(value = PushMode.AUTOMATIC, transport = Transport.WEBSOCKET_XHR)
  * public class AppShell implements VaadinAppShell {
  * }
  * </code>

flow-server/src/main/java/com/vaadin/flow/server/AppShellRegistry.java

@@ -25,10 +25,12 @@
 import org.jsoup.nodes.Document;
 import org.jsoup.nodes.Element;
 
+import com.vaadin.flow.component.PushConfiguration;
 import com.vaadin.flow.component.page.BodySize;
 import com.vaadin.flow.component.page.Inline;
 import com.vaadin.flow.component.page.Inline.Position;
 import com.vaadin.flow.component.page.Meta;
+import com.vaadin.flow.component.page.Push;
 import com.vaadin.flow.component.page.TargetElement;
 import com.vaadin.flow.component.page.AppShellConfigurator;
 import com.vaadin.flow.component.page.Viewport;
@@ -260,6 +262,26 @@ public void modifyIndexHtml(Document document, VaadinRequest request) {
                         document.body()::appendChild));
     }
 
+    /**
+     * Modifies PushConfiguration instance based on the {@link Push}
+     * annotation on {@link AppShellConfigurator}
+     *
+     * @param pushConfiguration the PushConfigration instance to modify
+     */
+    public void modifyPushConfiguration(PushConfiguration pushConfiguration) {
+        List<Push> pushAnnotations = getAnnotations(Push.class);
+        if (pushAnnotations.size() > 1) {
+            throw new InvalidApplicationConfigurationException(String.format(
+                    AppShellRegistry.ERROR_MULTIPLE_ANNOTATION,
+                    Push.class.getSimpleName()));
+        } else if (!pushAnnotations.isEmpty()) {
+            Push push = pushAnnotations.get(0);
+            pushConfiguration.setPushMode(push.value());
+            pushConfiguration.setTransport(push.transport());
+        }
+    }
+
+
     private void insertElement(Element elm, Consumer<Element> action) {
         action.accept(elm);
         for (String cssQuery : UNIQUE_ELEMENTS) {

flow-server/src/main/java/com/vaadin/flow/server/communication/JavaScriptBootstrapHandler.java

@@ -38,6 +38,7 @@
 import com.vaadin.flow.server.VaadinResponse;
 import com.vaadin.flow.server.VaadinServletRequest;
 import com.vaadin.flow.server.VaadinSession;
+import com.vaadin.flow.server.AppShellRegistry;
 import com.vaadin.flow.shared.ApplicationConstants;
 import com.vaadin.flow.theme.ThemeDefinition;
 
@@ -122,12 +123,11 @@ protected BootstrapContext createAndInitUI(
         PushConfiguration pushConfiguration = context.getUI()
                 .getPushConfiguration();
         pushConfiguration.setPushUrl(pushURL);
+
+        AppShellRegistry registry = AppShellRegistry
+                .getInstance(session.getService().getContext());
+        registry.modifyPushConfiguration(pushConfiguration);
 
-        // TODO(manolo) this comment is left intentionally because we
-        // need to revise whether the info passed to client is valid
-        // when initialising push. Right now ccdm is not doing
-        // anything with push.
-        config.put("pushScript", getPushScript(context));
         config.put("requestURL", requestURL);
 
         return context;

flow-server/src/main/java/com/vaadin/flow/server/startup/VaadinAppShellInitializer.java

@@ -38,6 +38,7 @@
 import com.vaadin.flow.component.page.Inline;
 import com.vaadin.flow.component.page.Meta;
 import com.vaadin.flow.component.page.AppShellConfigurator;
+import com.vaadin.flow.component.page.Push;
 import com.vaadin.flow.component.page.Viewport;
 import com.vaadin.flow.function.DeploymentConfiguration;
 import com.vaadin.flow.router.PageTitle;
@@ -61,7 +62,7 @@
  */
 @HandlesTypes({ AppShellConfigurator.class, Meta.class, Meta.Container.class,
         PWA.class, Inline.class, Inline.Container.class, Viewport.class,
-        BodySize.class, PageTitle.class, PageConfigurator.class })
+        BodySize.class, PageTitle.class, PageConfigurator.class, Push.class })
 @WebListener
 public class VaadinAppShellInitializer implements ServletContainerInitializer,
         Serializable {

flow-server/src/test/java/com/vaadin/flow/server/MockServletServiceSessionSetup.java

@@ -7,7 +7,6 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
-
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -46,6 +45,7 @@ public class TestVaadinServletService extends VaadinServletService {
         private Router router;
         private List<BootstrapListener> bootstrapListeners = new ArrayList<>();
         private List<IndexHtmlRequestListener> indexHtmlRequestListeners = new ArrayList<>();
+        private VaadinContext context;
 
         public TestVaadinServletService(TestVaadinServlet testVaadinServlet,
                 DeploymentConfiguration deploymentConfiguration) {
@@ -113,6 +113,18 @@ public void modifyIndexHtmlResponse(IndexHtmlResponse response) {
 
             super.modifyIndexHtmlResponse(response);
         }
+
+        @Override
+        public VaadinContext getContext() {
+            if (context != null) {
+                return context;
+            }
+            return super.getContext();
+        }
+
+        public void setContext(VaadinContext context) {
+            this.context = context;
+        }
     }
 
     public class TestVaadinServlet extends VaadinServlet {
@@ -259,6 +271,10 @@ public String getContentType() {
     private TestVaadinServlet servlet;
     private TestVaadinServletService service;
     private MockDeploymentConfiguration deploymentConfiguration = new MockDeploymentConfiguration();
+    @Mock
+    private VaadinServletContext context;
+    @Mock
+    private AppShellRegistry appShellRegistry;
 
     public MockServletServiceSessionSetup() throws Exception {
         this(true);
@@ -310,6 +326,13 @@ public MockServletServiceSessionSetup(boolean sessionAvailable)
         }
 
         Mockito.when(request.getServletPath()).thenReturn("");
+
+        AppShellRegistry.AppShellRegistryWrapper attribute = new AppShellRegistry.AppShellRegistryWrapper(
+                appShellRegistry);
+        Mockito.when(context
+                .getAttribute(AppShellRegistry.AppShellRegistryWrapper.class))
+                .thenReturn(attribute);
+        service.setContext(context);
     }
 
     public TestVaadinServletService getService() {
@@ -344,6 +367,10 @@ public MockDeploymentConfiguration getDeploymentConfiguration() {
         return deploymentConfiguration;
     }
 
+    public AppShellRegistry getAppShellRegistry() {
+        return appShellRegistry;
+    }
+
     public WebBrowser getBrowser() {
         return browser;
     }

flow-server/src/test/java/com/vaadin/flow/server/communication/JavaScriptBootstrapHandlerTest.java

@@ -24,15 +24,20 @@
 import org.junit.Test;
 import org.mockito.Mockito;
 
+import com.vaadin.flow.component.PushConfiguration;
 import com.vaadin.flow.component.UI;
 import com.vaadin.flow.component.internal.JavaScriptBootstrapUI;
+import com.vaadin.flow.component.page.AppShellConfigurator;
+import com.vaadin.flow.component.page.Push;
 import com.vaadin.flow.dom.NodeVisitor.ElementType;
 import com.vaadin.flow.dom.TestNodeVisitor;
 import com.vaadin.flow.dom.impl.BasicElementStateProvider;
+import com.vaadin.flow.server.AppShellRegistry;
 import com.vaadin.flow.server.MockServletServiceSessionSetup;
 import com.vaadin.flow.server.MockServletServiceSessionSetup.TestVaadinServletResponse;
 import com.vaadin.flow.server.VaadinRequest;
 import com.vaadin.flow.server.VaadinSession;
+import com.vaadin.flow.shared.communication.PushMode;
 
 import elemental.json.Json;
 import elemental.json.JsonObject;
@@ -48,6 +53,10 @@ public class JavaScriptBootstrapHandlerTest {
     private VaadinSession session;
     private JavaScriptBootstrapHandler jsInitHandler;
 
+    @Push
+    static public class PushAppShell implements AppShellConfigurator {
+    }
+
     @Before
     public void setup() throws Exception {
         mocks = new MockServletServiceSessionSetup();
@@ -98,9 +107,7 @@ public void should_produceValidJsonResponse() throws Exception {
                 json.getObject("appConfig").get("serviceUrl"));
         Assert.assertEquals("http://localhost:8888/foo/", json.getObject("appConfig").getString("requestURL"));
 
-        // Using regex, because version depends on the build
-        Assert.assertTrue(json.getObject("appConfig").getString("pushScript")
-                .matches("^\\./VAADIN/static/push/vaadinPush\\.js\\?v=[\\w\\.\\-]+$"));
+        Assert.assertFalse(json.hasKey("pushScript"));
     }
 
     @Test
@@ -156,6 +163,57 @@ public void should_attachViewTo_Body_when_location() throws Exception {
         Mockito.verify(session, Mockito.times(1)).setAttribute(SERVER_ROUTING, Boolean.TRUE);
     }
 
+    @Test
+    public void should_respondPushScript_when_enabledInDeploymentConfiguration()
+            throws Exception {
+        mocks.getDeploymentConfiguration().setPushMode(PushMode.AUTOMATIC);
+
+        VaadinRequest request = mocks.createRequest(mocks,
+                "/foo/?v-r=init&foo");
+        jsInitHandler.handleRequest(session, request, response);
+
+        Assert.assertEquals(200, response.getErrorCode());
+        Assert.assertEquals("application/json", response.getContentType());
+        JsonObject json = Json.parse(response.getPayload());
+
+        // Using regex, because version depends on the build
+        Assert.assertTrue(json.getString("pushScript").matches(
+                "^\\./VAADIN/static/push/vaadinPush\\.js\\?v=[\\w\\.\\-]+$"));
+    }
+
+    @Test
+    public void should_invoke_modifyPushConfiguration()
+            throws Exception {
+        VaadinRequest request = mocks.createRequest(mocks,
+                "/foo/?v-r=init&foo");
+        jsInitHandler.handleRequest(session, request, response);
+
+        Mockito.verify(mocks.getAppShellRegistry())
+                .modifyPushConfiguration(Mockito.any(PushConfiguration.class));
+    }
+
+    @Test
+    public void should_respondPushScript_when_annotatedInAppShell()
+            throws Exception {
+        AppShellRegistry registry = mocks.getAppShellRegistry();
+        Mockito.doCallRealMethod().when(registry).setShell(PushAppShell.class);
+        registry.setShell(PushAppShell.class);
+        Mockito.doCallRealMethod().when(registry).getShell();
+        Mockito.doCallRealMethod().when(registry)
+                .modifyPushConfiguration(Mockito.any(PushConfiguration.class));
+
+        VaadinRequest request = mocks.createRequest(mocks, "/foo/?v-r=init&foo");
+        jsInitHandler.handleRequest(session, request, response);
+
+        Assert.assertEquals(200, response.getErrorCode());
+        Assert.assertEquals("application/json", response.getContentType());
+        JsonObject json = Json.parse(response.getPayload());
+
+        // Using regex, because version depends on the build
+        Assert.assertTrue(json.getString("pushScript").matches(
+                "^\\./VAADIN/static/push/vaadinPush\\.js\\?v=[\\w\\.\\-]+$"));
+    }
+
     private boolean hasNodeTag(TestNodeVisitor visitor, String htmContent, ElementType type) {
         Pattern regex = Pattern.compile(htmContent, Pattern.DOTALL);
         return visitor