@baris I've added some debug code in the place you mentioned. Having opened two browsers, each connected to a different NodeBB instance I see the following behaviour:
- there's a lot of keys being cleared all the time
- among them, if I modify widgets I see
widgets:globalbeing cleared but only on the instance that initiated the change. - the second instance shows no sign of clearing
widgets:global(and the change obviously is not visible on it) - this is consistent for any other change - navbar changes, profile edits...
So the question is: should I not be seeing the same cache key being cleared on both instances?
[UPDATE]
This looks interesting:
PUBSUB CHANNELS
*2
$27
db:0:adapter_key-request#/#
$28
db:0:adapter_key-response#/#
I see no pubsub_channel in our Redis instance...
[UPDATE 2]
It all seems clear to me now. In https://github.com/NodeBB/NodeBB/commit/e85aabbe74d7838185d0b102bf37a20c1a1b62a1 a logic was added that looks at isCluster to determine whether initialize "real" pub/sub mechanism or a "fake" local only. In our scenario we have instances running on separate machines and each instance is running just one NodeBB process. Therefore isCluster is false as determined by process.env.isCluster = ports.length > 1; in loader.js:118.
I am fixing this temporarily in our codebase by reversing the if...else if...else..if so that is does not look at isCluster in src/pubsub.js because I am not sure if "faking" or "forcing" NodeBB to recognize our scenario as clustered is correct and would not have any side-effects.
Advices?
To clarify, the code after my fix looks like this:
var pubsub;
if (nconf.get('redis')) {
pubsub = require('./database/redis/pubsub');
} else if (nconf.get('mongo')) {
pubsub = require('./database/mongo/pubsub');
} else {
var EventEmitter = require('events');
pubsub = new EventEmitter();
pubsub.publish = pubsub.emit.bind(pubsub);
}
Feel free to borrow it if it looks okay to you. It works for us
