Pipes should be escaped or replaced before sending to datadog

[hurricane766]

Hi,

This is how I'm using connect-datadog in my app:
var connectDatadog = require('connect-datadog');
app.use(connectDatadog({response_code: true, path: true, method: true}));

I've noticed that my syslogs are filling up with errors like this:

ERROR (dogstatsd.py:309): Error receiving datagram#012Traceback (most recent call last):#12 File "/opt/datadog-agent/agent/dogstatsd.py", line 297, in start#012 aggregator_submit(message)#12 File "/opt/datadog-agent/agent/aggregator.py", line 606, in submit_packets#012 parsed_packets = self.parse_metric_packet(packet)#12 File "/opt/datadog-agent/agent/aggregator.py", line 481, in parse_metric_packet#012 raise Exception('Metric value must be a number: %s, %s' % (name, raw_value))#012Exception: Metric value must be a number: node.express.router.response_code.all, url(api

I've got some javascript files missing obviously, but I didn't think this should be causing syslog errors. I wrote some more information out of /opt/datadog-agent/agent/aggregator.py and here is the packet that is being passed through to be parsed, as well as the associated error:

Packet:node.express.router.response_code.404:1|c|#route:/:url(api|components|app|bower_components|assets)/*,method:get,path:/app/shims/combos/1.js,response_code:404

Error: Metric value must be a number: node.express.router.response_code.404, url(api

aggregator.py does state that the schema of a dogstatsd packet is expected like this:
<name>:<value>|<metric_type>|@<sample_rate>|#<tag1_name>:<tag1_value>,<tag2_name>:<tag2_value>:<value>|<metric_type>...

For some reason it looks like the parser is seeing url(api as the value for node.express.router.response_code.404.

I'm not sure where the actual error is, but the parser is choking on these types of packets.

Thanks

[hurricane766]

Update from datadog support:

| is used by the statsd protocol to delimit the fields. When used in a tag, it
needs to be escaped or it'll break Dogstatsd parsing packet method 
and leads to some weird side effect errors.

The node-dogstatsd package needs to escape the | character (which is not
officially supported by Datadog), i.e. to replace it with something else.

[hurricane766]

I have verified that the problem is you can use pipes when defining express.js routes, and then node-connect-datadog is sending them to datadog. But datadog uses pipes to delimit fields.

For example

//This will match paths starting with `/ab` and `/ac`:
app.use('/a(b|c)', function (req, res, next) {
  next();
});