JDBC for caching/session storage

[DonaldChung-HK]

Describe The Problem To Be Solved
I am trying to deploy a distributed IAM and running a HA redis infrastructure will increase the complexity and chances of failure of the system. Thus, I propose adding JDBC support for external session storage.

Solution suggestion

• Details of the technical implementation
  • Add spring-jdbc-session dependency
  • review and disable any caching strategy that is not suitable for SQL
  • (Optional) support a separate datasource(database) for session storage, most HA MySQL options will benefit from having caching at a separate DB as most IAM data are written in a low frequency while catching and session are accessed at high frequency.
• Tradeoffs made in design decisions
  • May reduce performance as SQL are in general slower
• Caveats and considerations for the future
  • Addition of Postgres option as it offers faster distributed HA options such as CockroachDB