Update spring boot from 2.2.5.RELEASE to 4.0.6

.gitignore

@@ -7,3 +7,4 @@
 **/*.jar
 **/target
 .idea/
+**/**/project.iml

edu-spring-postgres/backend/Dockerfile

@@ -1,26 +1,47 @@
-# syntax=docker/dockerfile:1.4
+# syntax=docker/dockerfile:1.6
 
-FROM --platform=$BUILDPLATFORM maven:3.9-eclipse-temurin-21 AS builder
-WORKDIR /workdir/server
-COPY pom.xml /workdir/server/pom.xml
-RUN mvn dependency:go-offline
+# Stage 1: Build
+FROM maven:3.9.14-eclipse-temurin-25-alpine AS builder
 
-COPY src /workdir/server/src
-RUN mvn install
+RUN apk upgrade --available --no-cache
 
-FROM builder AS prepare-production
-RUN mkdir -p target/dependency
-WORKDIR /workdir/server/target/dependency
-RUN jar -xf ../*.jar
+WORKDIR /app
 
-FROM eclipse-temurin:21-jre-noble
+COPY pom.xml .
+
+RUN mvn --batch-mode --errors --quiet dependency:go-offline
+
+# Copy the relevant directory
+COPY src ./src
+
+# If check passes, build the jar
+RUN mvn --batch-mode --errors --quiet clean package -DskipTests
+
+# Extract the jar file using an efficient layout
+RUN java -Djarmode=tools -jar target/project.jar extract --layers --destination extracted
+
+# Stage 2: Run the application
+FROM eclipse-temurin:25.0.2_10-jre-alpine-3.23
+
+LABEL org.opencontainers.image.source=https://github.com/notalib/workshop-containerisation
+LABEL org.opencontainers.image.description="Spring Boot example application"
+
+# Upgrade packages
+RUN apk upgrade --available --no-cache
+
+# Copy the extracted jar contents from the builder container into the working directory in the runtime container
+# Every copy step creates a new docker layer
+# This allows docker to only pull the changes it really needs
+COPY --from=builder /app/extracted/dependencies/ ./
+COPY --from=builder /app/extracted/spring-boot-loader/ ./
+COPY --from=builder /app/extracted/snapshot-dependencies/ ./
+COPY --from=builder /app/extracted/application/ ./
 
-EXPOSE 8080
-VOLUME /tmp
-ARG DEPENDENCY=/workdir/server/target/dependency
-COPY --from=prepare-production ${DEPENDENCY}/BOOT-INF/lib /app/lib
-COPY --from=prepare-production ${DEPENDENCY}/META-INF /app/META-INF
-COPY --from=prepare-production ${DEPENDENCY}/BOOT-INF/classes /app
 COPY entrypoint.sh /entrypoint.sh
 RUN chmod +x /entrypoint.sh
+
+# Add a non-root user
+RUN addgroup --system spring && adduser --system --ingroup spring spring
+USER spring:spring
+
 ENTRYPOINT ["/entrypoint.sh"]

edu-spring-postgres/backend/entrypoint.sh

@@ -5,4 +5,12 @@ if [ -f /run/secrets/db-password ]; then
   export POSTGRES_PASSWORD="$(cat /run/secrets/db-password)"
 fi
 
-exec java -cp "app:app/lib/*" com.company.project.Application
+# Run Spring Boot app
+# Start the application jar - this is not the uber jar used by the builder
+# This jar only contains application code and references to the extracted jar files
+# This layout is efficient to start up and AOT cache (and CDS) friendly
+# -XX:+UseContainerSupport is on by default in Java 11+ but explicit is better than implicit.
+# -XX:MaxRAMPercentage=75.0 tells the JVM to use up to 75% of the container’s available memory for the heap. Leaving the remaining 25% for native memory, Metaspace, and thread stacks is a reasonable default for most applications.
+# -XX:+ExitOnOutOfMemoryError makes the JVM exit (and the container restart) rather than limping along in a degraded state when it runs out of memory
+
+exec java -XX:+UseContainerSupport -XX:MaxRAMPercentage=75.0 -XX:+ExitOnOutOfMemoryError -jar project.jar

edu-spring-postgres/backend/pom.xml

@@ -2,26 +2,24 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
-
-    <groupId>com.company</groupId>
-    <artifactId>project</artifactId>
-    <version>0.0.1-SNAPSHOT</version>
-    <packaging>jar</packaging>
-
-    <name>New App</name>
-    <description>My new SpringBoot app</description>
-
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>3.4.13</version>
+        <version>4.0.6</version>
         <relativePath/>
     </parent>
+    <groupId>com.company</groupId>
+    <artifactId>project</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>New App</name>
+    <description>My new SpringBoot app</description>
+    <packaging>jar</packaging>
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
-        <java.version>21</java.version>
+        <java.version>25</java.version>
+        <testcontainers.version>2.0.5</testcontainers.version>
     </properties>
 
     <dependencies>
@@ -44,6 +42,7 @@
         <dependency>
             <groupId>org.postgresql</groupId>
             <artifactId>postgresql</artifactId>
+            <version>42.7.11</version>
             <scope>runtime</scope>
         </dependency>
         <dependency>
@@ -60,43 +59,34 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
-            <exclusions>
-                <exclusion>
-                    <groupId>org.junit.vintage</groupId>
-                    <artifactId>junit-vintage-engine</artifactId>
-                </exclusion>
-            </exclusions>
         </dependency>
-
         <dependency>
-            <groupId>org.testcontainers</groupId>
-            <artifactId>testcontainers-junit-jupiter</artifactId>
-            <version>2.0.5</version>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-resttestclient</artifactId>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.testcontainers</groupId>
-            <artifactId>testcontainers</artifactId>
-            <version>2.0.5</version>
+            <artifactId>testcontainers-junit-jupiter</artifactId>
+            <version>${testcontainers.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.testcontainers</groupId>
             <artifactId>testcontainers-postgresql</artifactId>
-            <version>2.0.1</version>
+            <version>${testcontainers.version}</version>
             <scope>test</scope>
         </dependency>
-
         <dependency>
             <groupId>org.jsoup</groupId>
             <artifactId>jsoup</artifactId>
-            <version>1.18.3</version>
+            <version>1.22.2</version>
             <scope>test</scope>
         </dependency>
-
     </dependencies>
 
     <build>
+        <finalName>${project.artifactId}</finalName>
         <plugins>
             <plugin>
                 <groupId>org.springframework.boot</groupId>

edu-spring-postgres/backend/src/main/java/com/company/project/Application.java

@@ -6,7 +6,7 @@
 @SpringBootApplication
 public class Application {
 
-    public static void main(String[] args) {
-        SpringApplication.run(Application.class, args);
-    }
+  public static void main(String[] args) {
+    SpringApplication.run(Application.class, args);
+  }
 }

edu-spring-postgres/backend/src/main/java/com/company/project/controller/GreetingController.java

@@ -0,0 +1,77 @@
+package com.company.project.controller;
+
+import com.company.project.entity.Greeting;
+import com.company.project.service.IGreetingService;
+import java.util.UUID;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.server.ResponseStatusException;
+
+@Controller
+public class GreetingController {
+
+    private static final Logger log = LoggerFactory.getLogger(GreetingController.class);
+
+    private final IGreetingService iGreetingService;
+
+    @Autowired
+    public GreetingController(IGreetingService iGreetingService) {
+        this.iGreetingService = iGreetingService;
+    }
+
+    @GetMapping("/")
+    public String showHome(Model model) {
+        String greetingDocker = "Docker";
+        log.info("GET / — loading default greeting with name='{}'", greetingDocker);
+        Greeting dockerGreeting = iGreetingService.showHome(greetingDocker).orElseThrow(() -> {
+            log.warn("Greeting with name='{}' not found", greetingDocker);
+            return new ResponseStatusException(HttpStatus.NOT_FOUND, "Greeting '" + greetingDocker + "' not found");
+        });
+        log.info("Loaded greeting: '{}'", dockerGreeting.getName());
+        model.addAttribute("name", dockerGreeting.getName());
+        model.addAttribute("body", "Connected to database!");
+        return "greeting-single";
+    }
+
+    @GetMapping("/greetings")
+    public String listGreetings(Model model) {
+        log.info("GET /greetings — listing all greetings");
+        Iterable<Greeting> greetings = iGreetingService.listGreetings();
+        model.addAttribute("greetings", greetings);
+        return "greetings";
+    }
+
+    @GetMapping("/greetings/{id}")
+    public String sayHello(@PathVariable UUID id, Model model) {
+        log.info("GET /greetings/{} — looking up greeting", id);
+        Greeting greeting = iGreetingService.sayHello(id).orElseThrow(() -> {
+            log.warn("Greeting with id='{}' not found", id);
+            return new ResponseStatusException(HttpStatus.NOT_FOUND, "Greeting '" + id + "' not found");
+        });
+        log.info("Found greeting id='{}' name='{}'", id, greeting.getName());
+        model.addAttribute("name", greeting.getName());
+        model.addAttribute("body", "Greeting #" + id);
+        return "greeting-single";
+    }
+
+    @GetMapping("/new")
+    public String newGreetingForm() {
+        return "new";
+    }
+
+    @PostMapping("/greetings")
+    public String createGreeting(@RequestParam String name) {
+        log.info("POST /greetings — creating new greeting with name='{}'", name);
+        Greeting greeting = iGreetingService.createGreeting(name);
+        log.info("Saved new greeting id='{}' name='{}'", greeting.getId(), greeting.getName());
+        return "redirect:/greetings/" + greeting.getId();
+    }
+}