Multi-module spring-boot project, container can't be started, got Error "Could not find or load main class"

Environment:

• *Jib version: * 2.2.0
• Build tool: Maven 3.6.3
• *OS: * Windows 10

Description of the issue: Hello,

i have a multi-module spring-boot-project, as follows the project structure: (root - Parent Project “Zi_DeliveryService”) ± delivery-service # Sub-Module with a main class, it has module “delivery-common” as dependency ± delivery-common #Sub-Module, does not have main class

However, by running “mvn clean deploy jib:build” in the root, the image can be built and pushed into image-repo, but the container cannot be started, and the error message is “Could not find or load main class com.zi.delivery.Application”.

If i want to containerize the sub-module, by runing “mvn clean package jib:build -pl delivery-service -am” Image can not even be built, I got unauthorized error

Ways to reproduce: Way 1.
If i run Jenkins-Skript: sh ‘mvn clean deploy jib:build -Dmaven.test.skip=true -Djib.from.auth.username=$imageRepoUser -Djib.from.auth.password=$imageRepoPassword -Djib.to.auth.username=$imageRepoUser -Djib.to.auth.password=$imageRepoPassword’

Image can be built and pushed to image-repo, no unauthorized error. But Container cannot be started, Error message: “Could not find or load main class com.zi.delivery.Application” in the pod

Way 2. Jenkins-Skript: sh ‘mvn clean deploy jib:build -pl delivery-service -am -Dmaven.test.skip=true -Djib.from.auth.username=$imageRepoUser -Djib.from.auth.password=$imageRepoPassword -Djib.to.auth.username=$imageRepoUser -Djib.to.auth.password=$imageRepoPassword’

The jenkins-job will fail and the error message is: [ERROR] I/O error for image [harbor.zi.com:443/open-jdk-8u242-base-image]: [ERROR] java.net.SocketException [ERROR] Socket closed [INFO] ------------------------------------------------------------------------ [INFO] ZiDeliveryService …SUCCESS [ 13.479 s] [INFO] delivery-common …SUCCESS [ 4.247 s] [INFO] delivery-service …FAILURE [ 8.629 s] [INFO] ------------------------------------------------------------------------ [INFO] BUILD FAILURE [ERROR] Failed to execute goal com.google.cloud.tools:jib-maven-plugin:2.2.0:build (default-cli) on project delivery-service: Build image failed, perhaps you should make sure your credentials for ‘harbor.zi.com:443’ are set up correctly. Unauthorized for harbor.zi.com:443: 500 Internal Server Error -> [Help 1]

Details: (1) There is @SpringBootApplication Annotation in the main Class (2) I only wrote one main class, which is in the delivery-service module (3) In the parent-pom, the jib-plugin is in the part PluginManagement; in the child-pom of module “delivery-service”, i must specify the mainClass with <mainClass>com.zi.delivery.Application</mainClass>, otherwise the error message will be “Could not find or load main class ${start-class}”; in the child-pom of the module “delivery-common”, i set jib.skip as true.

jib-maven-plugin Configuration in parent pom:

<build>
        <pluginManagement>
            <plugins>
                <plugin>
                    <groupId>com.google.cloud.tools</groupId>
                    <artifactId>jib-maven-plugin</artifactId>
                    <version>${jib-maven-plugin.version}</version>
                </plugin>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                    <version>${spring.boot.version}</version>
                </plugin>
              </plugins>
            </pluginManagement>
         </build>

jib-maven-plugin Configuration in child pom of the module “delivery-service”, which contains a main class:

<build>
                <plugins>
                    <plugin>
                        <groupId>com.google.cloud.tools</groupId>
                        <artifactId>jib-maven-plugin</artifactId>
                        <configuration>
                            <container>
                                <mainClass>com.zi.delivery.Application</mainClass>
                                <jvmFlags>
                                    <jvmFlag>-Xmx3G</jvmFlag>
                                </jvmFlags>
                            </container>
                            <from>
                                <image>${image.from}</image>
                            </from>
                            <to>
                                <image>${image.to}</image>
                                <tags>
                                    <tag>${project.version}</tag>
                                    <tag>${image.tag}</tag>
                                </tags>
                            </to>
                        </configuration>
                    </plugin>
                    <plugin>
                       <groupId>org.springframework.boot</groupId>
                       <artifactId>spring-boot-maven-plugin</artifactId>
                       <configuration>
                             <mainClass>com.zi.delivery.Application</mainClass>
                            <executable>true</executable>
                       </configuration>
                       <executions>
                          <execution>
                             <goals>
                                <goal>repackage</goal>
                             </goals>
                         </execution>
                      </executions>
                   </plugin>
                </plugins>
            </build>

jib-maven-plugin Configuration in child pom of the other module “delivery-common”, which does not have any main class, and jib.skip is set as true:

    <properties>
        <jib.skip>true</jib.skip>
    </properties>

Please give me some advise, thank you very much.

Best regards, Zi

[SangZi]

Hi @chanseokoh,

today i tried the following and the Error “Could not find or load main class” is gone, and i can build and push image to harbor, and i also can start container.

What i did:

1. parent-pom: only do one thing, set jib in as profile

    <profile>
        <id>jib</id>
        <build>
            <plugins>
                <plugin>
                    <groupId>com.google.cloud.tools</groupId>
                    <artifactId>jib-maven-plugin</artifactId>
                    <version>${jib-maven-plugin.version}</version>
                    <configuration>
                        <container>
                           <!-- THE MAIN CLASS PATH OF YOUR MODULE WITH MAIN CLASS -->
                            <mainClass>com.zi.delivery.Application</mainClass>
                        </container>
                        <from>
                            <image>${image.from}</image>
                        </from>
                        <to>
                            <image>${image.to}</image>
                            <tags>
                                <tag>${project.version}</tag>
                                <tag>${image.tag}</tag>
                            </tags>
                        </to>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>

2. In the module with mainClass, in my use-case “delivery-service”

• set NOTHING regarding jib

• set “spring-boot-maven-plugin” as follows:

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <mainClass>com.zi.delivery.Application</mainClass>
                    <executable>true</executable>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </build>

I refered to the link https://github.com/GoogleContainerTools/jib/issues/1539 , and the answer from andxu

3. In all the other modules, without mainClass, set jib.skip, in my use-case “delivery-common”

<properties>
    <jib.skip>true</jib.skip>
</properties>

4. Run with

mvn clean deploy jib:build -Pjib -Dmaven.test.skip=true -Djib.from.auth.username=$harboruser -Djib.from.auth.password=$harborpassword -Djib.to.auth.username=$harboruser -Djib.to.auth.password=$harborpassword

PS: at the end, through it works. But, i could not explain, why i cannot jib:build locally in console and get the Unauthorized 500 Internal Server Error from Harbor, and why it only works via jenkins-job.

BR, Zi

[SangZi]

Hi @chanseokoh

thank you very much!

Yes, as you said, in my case, the problem is, spring-boot-maven-plugin runs in both delivery-service and deliver-common, as this plugin is defined in <pluginManagement>, and run in all sub-modules, so <goal>repackage</goal> is set in the module with mainClass and not only .jar file, but also a .jar.original file is created in this sub-module.

I am thinking maybe some configuration is missing in my computer (proxy or something else), i am trying to set no_proxy for the harbor link on my computer. If i can do it sucessfully, I will give an update here.

BR, Zi