Record a service deployment failure troubleshooting

background

Last Friday, after the local development of a certain function was completed , It needs to be deployed to the offline environment for front and rear end joint commissioning . Prompt during deployment “ The process restarts repeatedly ” So the deployment fails , When starting locally, the code can start normally .

The screening process

First log in to the deployed offline machine , View the deployment log , Prompt in the discovery log “war Package is damaged or invalid ”. decompression war package , Tips war Package is empty , So there should be an error when building the package （ When building packages , The company's platform has always been prompted that the construction and packaging have been successful , So at first, I thought there was a problem with the compiled or deployed script , No problem found after inspection ）.

Then check the log of the build package , I found that there was a mistake in this place , The reason for the error is

[ERROR] Failed to execute goal org.springframework.boot:spring-boot-maven-plugin:2.6.7:repackage (repackage) on project demo: Execution repackage of goal org.springframework.boot:spring-boot-maven-plugin:2.6.7
:repackage failed: Unable to find a single main class from the following candidates [com.example.demo.DemoApplication, com.example.demo.service.MainService] -> [Help 1]

It's easy to find the cause of the error , The error prompt has stated that there is more than one main function in the code . And already in [] The classes with main functions are marked in , We just need to delete the redundant main functions or in pom Just indicate the main function in the file .

terms of settlement

I'm here because another main function was inadvertently brought in , So delete the redundant main function . In addition to removing redundant main functions , We can still do that pom Specify the main function in the file . Or use @SpringBootApplication Annotation is OK .

stay pom The document specifies

<plugin>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-maven-plugin</artifactId>
    <version>1.5.9.RELEASE</version>
    <configuration>
        <mainClass>com.xx.xxx.startApp</mainClass>
    </configuration>
    <executions>
        <execution>
            <goals>
                <goal>repackage</goal>
            </goals>
        </execution>
    </executions>
</plugin>

Use @SpringBootApplication annotation

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class DemoApplication {
    

    public static void main(String[] args) {
    
        SpringApplication.run(DemoApplication.class, args);
    }

}

This can also solve the above problems .

reflection

Why is it IDEA It can start normally in ？

because IDEA The main function is explicitly specified in the configuration of .

PS： The project construction failed, but the company platform suggested that the construction and packaging were successful, which misled me for a long time ==