feat(redis-v5): add new command to enable keyspace notifications

[coreypurcell]

Creates a new command for Redis.

heroku redis:keyspace-notifications HEROKU_REDIS_CPURCELL_GREEN_URL -c 'AKE' -a cp-testing

Adds another field to the info command

heroku redis:info -a cp-testing
=== redis-cpurcell-aerodynamic-53841 (HEROKU_REDIS_CPURCELL_GREEN_URL)
Plan:                   Premium 0
Status:                 available
Created:                2020-09-10 18:39
Version:                6.0.6
Timeout:                300
Maxmemory:              noeviction
Maintenance:            not required
Maintenance window:     Wednesdays 18:00 to 22:00 UTC
Persistence:            AOF
HA Status:              Available
Requires TLS:           Yes
Keyspace Notifications: AKE
=== redis-cpurcell-spherical-17414 (HEROKU_REDIS_CPURCELL_PUCE_URL)
Plan:                   Premium 0
Status:                 available
Created:                2020-09-10 18:20
Version:                6.0.6
Timeout:                300
Maxmemory:              noeviction
Maintenance:            not required
Maintenance window:     Wednesdays 18:00 to 22:00 UTC
Persistence:            AOF
HA Status:              Available
Requires TLS:           Yes
Keyspace Notifications: Disabled

Help output

set the keyspace notifications configuration

USAGE
  $ heroku redis:keyspace-notifications [DATABASE]

OPTIONS
  -a, --app=app        (required) app to run command against
  -c, --config=config  (required) set keyspace notifications configuration
  -r, --remote=remote  git remote of app to use

DESCRIPTION
  Set the configuration to enable keyspace notification events:
       K     Keyspace events, published with __keyspace@<db>__ prefix.
       E     Keyevent events, published with __keyevent@<db>__ prefix.
       g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
       $     String commands
       l     List commands
       s     Set commands
       h     Hash commands
       z     Sorted set commands
       t     Stream commands
       x     Expired events (events generated every time a key expires)
       e     Evicted events (events generated when a key is evicted for maxmemory)
       m     Key miss events (events generated when a key that doesn't exist is accessed)
       A     Alias for "g$lshztxe", so that the "AKE" string means all the events except "m".

       pass an empty string ('') to disable keyspace notifications

[RasPhilCo]

@coreypurcell looks good! We try not to have hyphenated command names, if possible, but leveraging your experience here: is keyspace-notifications the best command name?

[coreypurcell]

@RasPhilCo the actual redis key is notify-keyspace-events but the docs call it Keyspace notifications. I don't know of any other way to refer to it.

[RasPhilCo]

🏄

[coreypurcell]

@RasPhilCo what needs to happen to get this shipped? We need a customer to test it out ASAP