Configuring session namespace does not change activeSessionsKey

[goeh]

Task List

• Steps to reproduce provided
• Stacktrace (if present) provided
• Example that reproduces the problem uploaded to Github
• Full description of the issue provided (see below)

Steps to Reproduce

Change the default namespace for session keys in Redis:

micronaut.session.http.redis.namespace: 'myapp_sessions:'

Sessions are stored in Redis with the namespace prefix, but the key holding active sessions still uses the default prefix micronaut.session:

If you want active sessions to be under the same namespace you must also change active-sessions-key to include your namespace prefix, like this:

micronaut.session.http.redis.active-sessions-key: 'myapp_sessions:active-sessions'

Expected Behaviour

I expected active sessions to be stored with the namespace prefix when I configured namespace.

Actual Behaviour

Active sessions uses the default prefix "micronaut.session:' unless you explicitly configure micronaut.session.http.redis.active-sessions-key.

The key is prefixed with namespace when the class is instantiated but it is not changed when namespace is changed.
https://github.com/micronaut-projects/micronaut-redis/blob/master/redis-lettuce/src/main/java/io/micronaut/configuration/lettuce/session/RedisHttpSessionConfiguration.java#L42

IMO the behavior should be changed. If that's not possible due to the breaking change, it should be documented with a warning to avoid unexpected namespace pollution.

Some might argue that finding all active sessions (cross namespaces) using a single key is a feature. But I think that's a corner case.

Environment Information

• Operating System: MacOS 10.15.5
• Micronaut Version: 1.3.7
• JDK Version: OpenJDK 11.0.7

Example Application

• TODO: link to github repository with example that reproduces the issue