I have a Spring Boot application which uses Hibernate, and HikariDataSource / HikariPool to talk to the database.
A special feature in the app triggers database restart. Currently this breaks the connections in HikariPool:
Caused by: org.postgresql.util.PSQLException: ERROR: relation "relation_which_really_exists" does not exist Position: 113 at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2532) at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:2267) at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:312) at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:448) at org.postgresql.jdbc.PgStatement.execute(PgStatement.java:369)
Old version of the app does call programmatically
org.hibernate.SessionFactory.close(); which causes restart of HikariDataSource / HikariCP:
2020-08-17T11:36:42.628Z [qtp1340328248-76] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-1 - Shutdown initiated... 2020-08-17T11:36:42.698Z [qtp1340328248-76] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-1 - Shutdown completed. 2020-08-17T11:36:51.266Z [qtp1340328248-12] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-2 - Starting... 2020-08-17T11:36:51.515Z [qtp1340328248-12] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-2 - Start completed.
I would like to do the same, but how can I programmatically restart the connection pool in my app? I’ve seen things like Spring Boot – Handle to Hibernate SessionFactory to get a handle to sessionFactory, and maybe something similar to get a handle to DataSource or CP….but is it OK to close / restart those objects violently, is the Spring Boot context designer to handle such action properly?
There’s probably some HikariCP configuration parameters that I can start to experiment with to try reach the same end result, but replicating the old implementation tempts as the easiest / most figured out and most probable to reach same end result.
After some study, found out that you can get handle of HikariCP and trigger connection eviction by:
HikariDataSource hikariDs = (HikariDataSource) dataSource; HikariPoolMXBean poolBean = hikariDs.getHikariPoolMXBean(); poolBean.softEvictConnections();