Substitute environment variables in Hibernate configuration files

Current Situation

• JOC Cockpit offers the Hibernate layer for database access.
• This includes
  • to specify credentials for database access from a hibernate.cfg.xml file.
  • not to use credentials but to apply "Integrated Security" based on the run-time account that is used for JOC Cockpit. This mechanism is frequently applied for SQL Server on Windows and for Oracle using Oracle Wallet.

Desired Behavior

• Users would like to apply Kubernetes standard mechanisms to read secrets from a secure source and to inject secrets into containers.
• The Kubernetes CSI provider allows to expose environment variables holding secrets. Such environment variables are populated from a number of "Secrets Engines" including for example HashiCorp Vault.
• The JOC Cockpit should support substitution of environment variables in Hibernate configuration files.
  • Example:

    <?xml version="1.0" encoding="UTF-8" standalone="no"?>
    <hibernate-configuration>
           <session-factory>
                   <property name="hibernate.connection.driver_class">org.mariadb.jdbc.Driver</property>
                   <property name="hibernate.connection.password">${JS7_DBMS_PASSWORD}</property>
                   <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/jobscheduler200?serverTimezone=UTC${JS7_DBMS_URL_PARAMETER}</property>
                   <property name="hibernate.connection.username">${JS7_DBMS_USER}</property>
                   <property name="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</property>
                   <property name="hibernate.show_sql">false</property>
                   <property name="hibernate.format_sql">true</property>
                   <property name="hibernate.temp.use_jdbc_metadata_defaults">false</property>
                   <property name="javax.persistence.validation.mode">none</property>
                   <!-- Hikari Connection Pool -->
                   <property name="hibernate.connection.provider_class">org.hibernate.hikaricp.internal.HikariCPConnectionProvider</property>
                   <property name="hibernate.hikari.maximumPoolSize">10</property>
           </session-factory>
    </hibernate-configuration>
    

• • This means that the following environment variables will be replaced:
    • ${JS7_DBMS_USER}
    • ${JS7_DBMS_PASSWORD}
    • ${JS7_DBMS_URL_PARAMETER}
  • This should not work as a general substitution mechanism for environment variables but will replace the indicated variables with the given syntax only – including use of ${...}.

Patch

• This patch is available for release 2.5.2.
• https://download.sos-berlin.com/patches/2.5.2-patch/patch-20230315-JOC-1510-2.5.2.jar
• See attached Wiki page how to apply the patch.