Missing logger accessor attributes

[aks]

Code that uses redis.logger or redis.logger = other_logger fails when using MockRedis. The emulation should include these attributes.

[sds]

Happy to accept a pull request!

[jdelStrother]

AFAICT redis-rb doesn't implement logger accessors -

irb(main):007:0> Redis.new.logger
Traceback (most recent call last):
        1: from (irb):7
Redis::CommandError (ERR unknown command `logger`, with args beginning with:)

- I assume you're just asking for the ability to log redis commands as they're executed? eg:

irb(main):011:0> Redis.new(logger: Logger.new(STDOUT)).hgetall "foo"
D, [2021-05-12T16:29:05.939290 #76845] DEBUG -- : [Redis] command=HGETALL args="foo"
D, [2021-05-12T16:29:05.940348 #76845] DEBUG -- : [Redis] call_time=0.80 ms
=> {}

I started to implement it in mock-redis here: jdelStrother@2ba1a14 - though it's kind of tricky to do it cleanly. Redis has the advantage of pushing all commands through the process method, which gives a single entrypoint for logging. In my version I just attach logging to all public methods of the Database modules. In addition, some mock-redis methods are built on top of each other - eg hmget uses hget internally, so a single call to hmget produces multiple logs like this:

D, [2021-05-12T16:35:57.356922 #77623] DEBUG -- : [MockRedis] command=HMGET args="key" "a" "b" "c"
D, [2021-05-12T16:35:57.356943 #77623] DEBUG -- : [MockRedis] command=HGET args="key" "a"
D, [2021-05-12T16:35:57.356943 #77623] DEBUG -- : [MockRedis] command=HGET args="key" "b"
D, [2021-05-12T16:35:57.356943 #77623] DEBUG -- : [MockRedis] command=HGET args="key" "c"

which would be fixable by refactoring hget into public & private parts - eg:

def hget(key, field)
  _hget(key, field)
end
def hmget(key, *fields)
  fields.flatten.map { |f| _hget(key, f) }
end

private
def _hget(key, field)
  with_hash_at(key) { |h| h[field.to_s] }
end

since only the public methods are logged, but that's starting to sound like a lot of tedious work. Any suggestions on a better implementation?

[jdelStrother]

Actually scratch all that, jdelStrother@dde6209 seems a much saner approach. I'll submit a PR for proper review.

[sds]

Implemented in #211.