Blocking operations in TypedRequestArgumentBinder implementation

[thaDude]

I implemented a TypedRequestArgumentBinder which extracts information from the HttpRequest's Authentication instance and then does a DB look-up based on that information. Is this safe or will it lead to blocked event loop issues?

I run my application with:

  server:
    thread-selection: IO

but this setting does not apply in the binding context since it's executed before the controller code.

To give a more complete picture of what I am trying to accomplish:

• Custom SecurityRule processes Authentication instance -> does DB look-up -> adds returned entity to HttpRequest as attribute
• The TypedRequestArgumentBinder either reads from that attribute and only does the DB look-up if has not not already been set by the SecurityRule.

Micronaut 3.x changes allow having non-blocking SecurityRule implementations but if the above pattern breaks in the argument binding phase it won't work.

Thank you,

David