Fails to start with Java Buildpack v4.18 (offline): hibernate fails with unknown mariadb dialect

[gberche-orange]

-----> Downloading Maria Db JDBC 2.4.0 from https://java-buildpack.cloudfoundry.org/mariadb-jdbc/mariadb-jdbc-2.4.0.jar (found in cache)
[...]
0 of 2 instances running, 1 starting, 1 crashed
	
FAILED
	
Error restarting application: Start unsuccessful
[...]

Caused by: org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
	at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:244)
	at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:208)
	at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:189)
	at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51)
	at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
	at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:217)
	at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:189)
	at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352) 
	at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111) 
	at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:847) 
	at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:874) 
	at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:60) 
	at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:338) 
	at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:373) 
	at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:362) 
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637) 
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574) 
	... 24 common frames omitted 
Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set 
	at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.determineDialect(DialectFactoryImpl.java:100) 
	at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:54) 
	at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:137) 
	at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35) 
	at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:88) 
	at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:234) 
	... 40 common frames omitted

Root cause is that hibernate only supports natively mariadb starting in version 5.2.8 https://planet.jboss.org/post/mariadb_dialects.

Similar issue than https://github.com/orange-cloudfoundry/paas-templates/issues/299

[gberche-orange]

The hibernate version is pulled by spring-boot-starter-data-jpa

Latest 1.5.21.RELEASE still points to hibernate-core 5.0.12.Final.

This therefore would require a bump to 2.1.5.RELEASE which points to org.hibernate » hibernate-core 5.3.10.Final

[gberche-orange]

Alternative fixes:

• bump springboot to 2.1.5 to get hibernate mariadb support
  • See https://github.com/snicoll-demos/spring-boot-migration with step by steps commits
  • https://github.com/spring-projects/spring-boot/wiki/Spring-Boot-2.0-Migration-Guide
• workaround by temporary pinning mariadb driver version to an older 2.3.0 version. See https://github.com/orange-cloudfoundry/paas-templates/issues/299#issuecomment-496213245