Merge pull request #8 from penguineer/software-version

Display the software version

src/main/java/com/penguineering/gartenplus/ApplicationContextProvider.java

@@ -0,0 +1,23 @@
+package com.penguineering.gartenplus;
+
+import org.springframework.beans.BeansException;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+import org.springframework.lang.NonNull;
+import org.springframework.stereotype.Component;
+
+import java.util.Optional;
+
+@Component
+public class ApplicationContextProvider implements ApplicationContextAware {
+    private static ApplicationContext applicationContext = null;
+
+    @Override
+    public void setApplicationContext(@NonNull ApplicationContext applicationContext) throws BeansException {
+        ApplicationContextProvider.applicationContext = applicationContext;
+    }
+
+    public static Optional<ApplicationContext> getApplicationContext() {
+        return Optional.ofNullable(applicationContext);
+    }
+}

src/main/java/com/penguineering/gartenplus/ui/appframe/GartenplusHeader.java

@@ -1,10 +1,18 @@
 package com.penguineering.gartenplus.ui.appframe;
 
+import com.penguineering.gartenplus.ApplicationContextProvider;
 import com.penguineering.gartenplus.auth.user.UserDTO;
 import com.vaadin.flow.component.html.Div;
 import com.vaadin.flow.component.html.H1;
+import com.vaadin.flow.component.html.Span;
+import com.vaadin.flow.component.orderedlayout.FlexComponent;
 import com.vaadin.flow.component.orderedlayout.HorizontalLayout;
+import com.vaadin.flow.component.orderedlayout.VerticalLayout;
+import com.vaadin.flow.theme.lumo.LumoUtility;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
 
+import java.util.Map;
+import java.util.Optional;
 import java.util.function.Supplier;
 
 public class GartenplusHeader extends Div {
@@ -18,14 +26,40 @@ public GartenplusHeader(Supplier<UserDTO> currentUser) {
 
         headerLayout.add(new GartenplusLogo());
 
-        headerLayout.add(new H1("GartenPlus"));
+        HorizontalLayout headlineLayout = new HorizontalLayout();
+        headlineLayout.setPadding(false);
+        headlineLayout.setMargin(false);
+        headlineLayout.setAlignItems(FlexComponent.Alignment.BASELINE);
+        headerLayout.add(headlineLayout);
+
+        headlineLayout.add(new H1("GartenPlus"));
+
+        Optional.ofNullable(findVersion())
+                .or(() -> Optional.of("local"))
+                .map(Span::new)
+                .ifPresent(headlineLayout::add);
+
 
         Div spacer = new Div();
         spacer.setWidthFull();
         headerLayout.add(spacer);
+        headerLayout.setFlexGrow(1, spacer);
 
         headerLayout.add(new LoggedUserView(currentUser));
 
         this.add(headerLayout);
     }
+
+    private static String findVersion() {
+        // TODO better decoupling from the application context
+        return ApplicationContextProvider.getApplicationContext()
+                .map(c -> c.getBeansWithAnnotation(SpringBootApplication.class))
+                .map(Map::entrySet)
+                .flatMap(entries -> entries.stream().findFirst())
+                .map(Map.Entry::getValue)
+                .map(Object::getClass)
+                .map(Class::getPackage)
+                .map(Package::getImplementationVersion)
+                .orElse(null);
+    }
 }