2 Spring apps on different ports (Vaadin + REST API)

Question

A little bit of background:

I'm using Maven.

I have a SpringBoot Vaadin 24 project that also uses SpringBoot Security.

I also have a SpringBoot REST API based on Spring Web.

Both apps use Spring starters.

The Vaadin app has to have access to some of the REST API classes or viceversa because the Vaadin app has the DB access methods and other stuff while the API app simply exposes and defines routes.

The apps have to run on different ports. (example: Vaadin@8443 & API@8081)

What I've tried to do:

• I've tried using a single .pom initally using a custom @PropertySource for each app (started 2 Vaadin apps on the 2 ports)

• I've tried following this guide and made 3 .pom files (everything goes well but when I try to link the 2 apps including one in the dependency list of the other I get 2 Vaadin apps)

• I've tried running the apps in separate threads and that resulted in 2 Vaadin apps

• The last thing I tried was removing SpringBoot and use simple Spring but Vaadin after v14 has big problems with that.

What I think that happens:

I think that the Vaadin app dependencies are taking over the API app ones and everything becomes Vaadin if I include one app as a dependency in the other.

Vaadin app .pom file without the other app as a dependency:

<?xml version="1.0" encoding="UTF-8"?>
<!--
  ~ Copyright (c) 2023. Maxim Gabriel Nicolai Palotti
  ~ All rights reserved.
  -->

<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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.1.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <!-- Project from https://start.vaadin.com/project/4e52dedc-ceb8-4221-a2a7-59d966e78c3a -->
    <groupId>org.company.xxx</groupId>
    <artifactId>xxx</artifactId>
    <name>xxx</name>
    <version>1.0.0</version>
    <packaging>jar</packaging>

    <properties>
        <java.version>17</java.version>
        <vaadin.version>24.1.4</vaadin.version>
        <selenium.version>4.10.0</selenium.version>
    </properties>

    <repositories>
        <repository>
            <id>Vaadin Directory</id>
            <url>https://maven.vaadin.com/vaadin-addons</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.vaadin</groupId>
                <artifactId>vaadin-bom</artifactId>
                <version>${vaadin.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>com.vaadin</groupId>
            <!-- Replace artifactId with vaadin-core to use only free components -->
            <artifactId>vaadin-core</artifactId>
        </dependency>
        <dependency>
            <groupId>com.vaadin</groupId>
            <artifactId>vaadin-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.parttio</groupId>
            <artifactId>line-awesome</artifactId>
            <version>1.1.0</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.vaadin</groupId>
            <artifactId>vaadin-testbench-junit5</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <defaultGoal>spring-boot:run</defaultGoal>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <jvmArguments>-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=5151</jvmArguments>
                    <wait>500</wait>
                    <maxAttempts>240</maxAttempts>
                </configuration>
            </plugin>

            <plugin>
                <groupId>com.vaadin</groupId>
                <artifactId>vaadin-maven-plugin</artifactId>
                <version>${vaadin.version}</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>prepare-frontend</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <profiles>
        <profile>
            <!-- Production mode is activated using -Pproduction -->
            <id>production</id>
            <dependencies>
                <!-- Exclude development dependencies from production -->
                <dependency>
                    <groupId>com.vaadin</groupId>
                    <artifactId>vaadin-core</artifactId>
                    <exclusions>
                        <exclusion>
                            <groupId>com.vaadin</groupId>
                            <artifactId>vaadin-dev</artifactId>
                        </exclusion>
                    </exclusions>
                </dependency>
            </dependencies>
            <build>
                <plugins>
                    <plugin>
                        <groupId>com.vaadin</groupId>
                        <artifactId>vaadin-maven-plugin</artifactId>
                        <version>${vaadin.version}</version>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>build-frontend</goal>
                                </goals>
                                <phase>compile</phase>
                            </execution>
                        </executions>
                    </plugin>
                </plugins>
            </build>
        </profile>

        <profile>
            <id>it</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-maven-plugin</artifactId>
                        <executions>
                            <execution>
                                <id>start-spring-boot</id>
                                <phase>pre-integration-test</phase>
                                <goals>
                                    <goal>start</goal>
                                </goals>
                            </execution>
                            <execution>
                                <id>stop-spring-boot</id>
                                <phase>post-integration-test</phase>
                                <goals>
                                    <goal>stop</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>

                    <!-- Runs the integration tests (*IT) after the server is started -->
                    <plugin>
                        <groupId>org.apache.maven.plugins</groupId>
                        <artifactId>maven-failsafe-plugin</artifactId>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>integration-test</goal>
                                    <goal>verify</goal>
                                </goals>
                            </execution>
                        </executions>
                        <configuration>
                            <trimStackTrace>false</trimStackTrace>
                            <enableAssertions>true</enableAssertions>
                        </configuration>
                    </plugin>
                </plugins>
            </build>
        </profile>

    </profiles>
</project>

REST API .pom file without the other app as a dependency:

<?xml version="1.0" encoding="UTF-8"?>
<!--
  ~ Copyright (c) 2023. Maxim Gabriel Nicolai Palotti
  ~ All rights reserved.
  -->

<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.1.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>org.company.yyy</groupId>
    <artifactId>yyy</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>yyy</name>
    <description>A standard API</description>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Answer 1

With the help of maven multi module you should be able to solve your problem.

1. Move Spring starter in parent module pom
2. Make Vaadin and Rest API module as the child module of parent module.
3. Further divide the Rest API module in 2 sub module a) App Module containing Main Class, Controller classes and application property. b) Domain Module containing Services and Entities.
4. Include only the 3.b as dependency in your Vaadin module.
5. Include 3.b as dependency in App Module 3.a as well.
6. Run Both Application main class separately.

You can check this sample https://github.com/ashishkumar-07/vaadin-multi-module-example.This is the fork of official Vaadin multi module sample