Setting PostgreSQL max_connections value in properties gives PSQLException

[Cécile Fécherolle]

Hi,

I'm using the library for my tests with a PostgreSQL database and the Zonky provider.
I have tried setting the PostgreSQL max_connections property in my Spring Boot configuration, like this:

zonky:
  test:
    database:
      postgres:
        client:
          properties:
            max_connections: 300

When launching a test class, the Spring Boot context fails to load and gives me the following error:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is io.zonky.test.db.shaded.com.google.common.util.concurrent.UncheckedExecutionException: io.zonky.test.db.provider.ProviderException: Unexpected error when prefetching a database; nested exception is java.lang.RuntimeException: org.postgresql.util.PSQLException: Unsupported property name: max_connections

After diving a bit deeper in the source code, I found that the enum org.postgresql.PGProperty is being used by the lib as a reference to set the properties of the PostgreSQL database. Problem is: this enum does not contain any "max connections" value.

I'm unsure how this configuration is supposed to be working, could someone help me?
Thank you.

[Cécile Fécherolle]

Ok, my bad, I used client.properties when it should have been server.properties 😅
Problem solved! Feel free to delete this issue.

[Tomáš Vaněk]

Ok, glad to hear it works as expected 🙂