How can I tell if connections are being routed to the reader node?

[efenderbosch-atg]

I have all classes that have a Spring JPA repo injected tagged w/ @Transactional(readOnly = true) and individual functions tagged w/ @Transactional(readOnly = write) if any rows are inserted/updated/deleted.

I can see the driver is introspecting the topology and finding the writer and reader nodes:

11:36:36.653 TRACE [nio-8084-exec-2] s.a.j.h.RdsHostListProvider              : Topology: 
   HostSpec[host=qa-reader.xxxx.us-east-1.rds.amazonaws.com, port=3306, READER, AVAILABLE, weight=1905, 2024-05-07 15:36:36.624203]
   HostSpec[host=qa.xxxx.us-east-1.rds.amazonaws.com, port=3306, WRITER, AVAILABLE, weight=5, 2024-05-07 15:36:36.237519]

But I also see logs like this, which seem to indicate that it isn't routing to the reader node:

11:36:36.624 TRACE [nio-8084-exec-2] s.a.jdbc.states.SessionStateServiceImpl  : Current session state:
autoCommit: true -> true
readOnly: false -> false
catalog: xxxx -> (blank)
schema: (blank) -> (blank)
holdability: (blank) -> (blank)
networkTimeout: 0 -> 5000
transactionIsolation: 4 -> (blank)
typeMap: (blank) -> (blank)

I have loggers turned up in application.yml:

spring:
  datasource:
    driver-class-name: software.amazon.jdbc.Driver
    hikari:
      data-source-properties:
        keepSessionStateOnFailover: true
      exception-override-class-name: software.amazon.jdbc.util.HikariCPSQLException

logging.level:
  software.amazon.jdbc: trace
  software.amazon.jdbc.plugin.DefaultConnectionPlugin: debug
  com.zaxxer.hikari: trace
  com.mysql: trace
  org.springframework.data.jpa: debug

How can I verify that my read-only transactions are going to the reader node?

[efenderbosch-atg]

Figured it out. I needed to enable the readWriteSplitting along w/ the default plugins.

spring.datasource.hikari.data-source-properties.wrapperPlugins=readWriteSplitting,auroraConnectionTracker,failover,efm2

However, now it isn't connecting to the reader node.

TRACE [nio-8084-exec-1] s.amazon.jdbc.DriverConnectionProvider   : Connecting to jdbc:mysql://qa-reader.xxxx.us-east-1.rds.amazonaws.com:3306/wavebid
WARN [nio-8084-exec-1] s.a.j.p.r.ReadWriteSplittingPlugin       : Failed to connect to reader host: 'wavebid-qa-catalog-v2-reader.cna3kjeaiowf.us-east-1.rds.amazonaws.com:3306/'

[karenc-bq]

Hi @efenderbosch-atg, are you able to connect successfully to the reader instance endpoint wavebid-qa-catalog-v2-reader.cna3kjeaiowf.us-east-1.rds.amazonaws.com without the read/write splitting plugin? Could you please provide us with the complete driver logs so we can root cause the connection issue?