Build jar file but (dockerize) Spring Boot Application starts

thadeuszlay :

I want to build a jar file from my Spring Boot Application, in order to build a docker image.

I select "package" resp. run maven with "package" as commandline. Instead it runs the whole Spring Boot Application. At the end it fails because it refers to a dockerize mysql db. Since the db and the Spring Boot application are in different networks, it fails of course:

2020-03-11 01:37:11.655 ERROR 6128 --- [           main] com.zaxxer.hikari.pool.HikariPool        : HikariPool-1 - Exception during pool initialization.

java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 5 times. Giving up.
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_171]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_171]
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_171]
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_171]

...
Caused by: java.net.UnknownHostException: shortenedurlmysqldb

My application.properties file:

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://shortenedurlmysqldb/bootdb2?createDatabaseIfNotExist=true&autoReconnect=true&maxReconnects=5&allowPublicKeyRetrieval=true&useSSL=false
spring.datasource.username=newuser
spring.datasource.password=password
spring.datasource.platform=mysql
spring.datasource.initialization-mode=always

My Dockerfile:

From openjdk:8
copy ./target/jugtours-0.0.1-SNAPSHOT.jar jugtours-0.0.1-SNAPSHOT.jar
CMD ["java","-jar","jugtours-0.0.1-SNAPSHOT.jar"]

My application.yml

spring:
  profiles:
    active: spring.profiles.active@
  security:
    oauth2:
      client:
        registration:
          okta:
            client-id: [...secret...]
            client-secret: [...secret...]
            scope: openid, email, profile
        provider:
          okta:
            issuer-uri: [...secret...]

I don't understand why the Spring Boot Application has to be started to begin with. Can't maven create a jar file without starting the Spring Boot App?

MyTwoCents :

I think its happening because you have some TestCases, even if you have added none, default Spring boot will have a empty Test File.

Try to skip testcases while mvn package trigger

mvn package -DskipTests