Cannot call redis.get() function inside websocket ping

Question

I have the following node.js code running well, but I cannot seem to get console.log to execute - what could the reason be? The redis is in scope and the redis.get() works fine in an earlier location (so I know the syntax is fine).. The console.log that does not execute is commented with the line "# cannot execute this line" in the code. Would be grateful for any pointers on how to debug..

The program prints out 'pong' and 'pong2', so I know it is responding to a ping.

var WebSocketServer = require('ws').Server
var wss = new WebSocketServer({
    port: 8080
});
var redis = redis_server.createClient(6379, 'localhost');

wss.on('connection', function(ws) {
    ws_auth(redis, ws, function(authresult, uid) {
        if (!authresult) {
            ws.close();
            return;
        }
        ws.on('ping', function() {
            console.log('pong')
            var cookie = ws.upgradeReq.headers.cookie;
            cookie_json = JSON.parse(cookie);
            redis.get('session:' + cookie_json.sessionid, function(err, value) {
                console.log(getDateTime() + ': value ' + value + " session exits");#cannot execute this line
            });
            ws.pong();
            console.log('pong2')
        });
    });
});

Is some client sending a `ping` message to your server to trigger that first `console.log()` statement? You may want to read this: http://stackoverflow.com/a/10586583/816620. — jfriend00, Apr 11 '15 at 02:12
@jfriend00 Thanks - The program prints out 'pong', so I know it is responding to a ping. — Trewq, Apr 11 '15 at 02:15
then perhaps you should clarify in your question which `console.log()` you're asking about. — jfriend00, Apr 11 '15 at 02:16
@jfriend00 I did - the code says "# cannot execute this line" - but I will add this to the question body rather than the code. — Trewq, Apr 11 '15 at 02:20
What is `ws_auth()`? It's being passed the `redis` handle, so it may be doing stuff to it that is causing `redis.get()` to fail somehow. — robertklep, Apr 11 '15 at 06:50
Add try catch block around the code to see what exception is being thrown. May be that can give you some pointers. — andHapp, Apr 11 '15 at 17:52

score 0 · Answer 1 · answered Apr 11 '15 at 02:22

0

Perhaps the JSON.parse is throwing an error which is being swallowed. It would be valuable to determine if the reddit server is receiving an event or not.

answered Apr 11 '15 at 02:22

Venar303

313
3
6

Thank for the reply! I updated the code to reflect that is prints pong and pong2 (shows that it is going through the code). cookie_json.sessionid also evaluated properly (I replaced the whole key with 'name' and no difference. I also ran redis in monitor mode, and I see that that the string gets set in redis, but the command from the .js program never reaches the redis server. – Trewq Apr 11 '15 at 02:29

Cannot call redis.get() function inside websocket ping

1 Answers1