Is it possible to support AWS MemoryDB AZ?

[nickngsr]

AWS MemoryDB is currently limited to Valkey 7.3, and therefore there is no availability_zone presented on a HELLO, however it is present on an INFO SERVER.

HELLO 3:

1# "server" => "redis"
2# "version" => "7.3.0"
3# "proto" => (integer) 3
4# "id" => (integer) 70832
5# "mode" => "cluster"
6# "role" => "master"
7# "modules" => (empty array)

INFO SERVER:

# Server
redis_version:7.2.4
server_name:valkey
valkey_version:7.3.0
redis_git_sha1:0
redis_git_dirty:0
redis_build_id:0
redis_mode:cluster
os:Amazon MemoryDB
arch_bits:64
monotonic_clock:ARM CNTVCT @ 121 ticks/us
multiplexing_api:epoll
atomicvar_api:c11-builtin
gcc_version:0.0.0
process_id:1
run_id:
tcp_port:6379
server_time_usec:1768266036089426
uptime_in_seconds:1066504
uptime_in_days:12
hz:10
configured_hz:10
lru_clock:6658356
executable:-
config_file:-
availability_zone:eu-west-1b

Is there a method of retrieving that 'availability_zone' so we can use the ReadNodeSelector function?

[rueian]

Upgrading the server to 8.1 or above might be the easiest way.

Otherwise, we may need to change these lines to get AZ from the response of the INFO command.

valkey-go/cluster.go

Lines 277 to 284 in ff09074

	for j := i + 1; j < i+4 && j < len(g.nodes); j++ {
	wg.Add(1)
	go func(wg *sync.WaitGroup, info *NodeInfo) {
	info.AZ = info.conn.AZ()
	wg.Done()
	}(&wg, &g.nodes[j])
	}
	g.nodes[i].AZ = g.nodes[i].conn.AZ()

[nickngsr]

Unfortunately MemoryDB doesn't have the option for anything higher than 7.3 yet. I assume that when 9.1 is released, given the efforts around data durability, it is likely MemoryDB will get that as the next version.

[nickngsr]

had a look at seeing how it can be implemented, and came up with the commit nickngsr@6791e12, doesn't feel like a particularly clean way of doing it, but it does work.

[rueian]

had a look at seeing how it can be implemented, and came up with the commit nickngsr@6791e12, doesn't feel like a particularly clean way of doing it, but it does work.

Cool, it looks good to me generally. Would you like to open a PR?