NSQ Output plugin

[jrxFive]

NSQ output plugin #309, following the NSQ methodology output is a producer
to one instance of NSQD. The go library does not accept array values. String
default for a Producer. Additionally service discovery is generally
done as a consumer.

Follows same methodology as Kafka Output without the tag reference.

[sparrc]

@jrxFive You've written this based on an outdated version of telegraf. The Write function doesn't take BatchPoints anymore, it takes []*client.Point

You should rebase your changes from HEAD, you'll see that the kafka output is quite a bit different too. It should actually simplify the Write function, because you will not need to deal with a .Raw or any Tag inheritance and parsing.

[sparrc]

@jrxFive Thank you very much for this! It looks good other than needing to be rebased

[jrxFive]

Sorry should have done that prior. It's a lot simpler than before :). I'll commit the change soon.

[sparrc]

What does port 4151 do?

[jrxFive]

4150 is an TCP listener port, 4151 is for HTTP even though the plugin isnt using that feature should I remove it?

[sparrc]

that's fine, you can keep it

[sparrc]

@jrxFive did you run the NSQ docker test? I'm getting a connection refused failure on OSX:

2015/10/27 13:12:38 INF    1 (192.168.99.100:4150) connecting to nsqd
2015/10/27 13:12:38 ERR    1 (192.168.99.100:4150) error connecting to nsqd - dial tcp 192.168.99.100:4150: getsockopt: connection refused
--- FAIL: TestConnectAndWrite (0.00s)
        Error Trace:    nsq_test.go:27
    Error:      No error is expected but got FAILED to send NSQD message: dial tcp 192.168.99.100:4150: getsockopt: connection refused

FAIL
FAIL    github.com/influxdb/telegraf/outputs/nsq    0.018s

[jrxFive]

Hmm I ran tests on a Linux VM and directly against a NSQ daemon. Weird I'll try on OSX to reproduce.

[sparrc]

@jrxFive I'm trying to debug, for some reason the NSQ container is not starting for me

[sparrc]

It looks like we're missing the "command", it needs to look like this in docker-compose

nsq:
    image: nsqio/nsq
    command: /nsqd
    ports:
        - "4150:4150"
        - "4151:4151"

[sparrc]

@jrxFive I'll make the change and merge this

[jrxFive]

Ahh good catch! Hmm why didnt this fail on the Circle-CI test? Its using Ubuntu Circle-CI? Wonder why OSX caught that though?

[sparrc]

CircleCI isn't currently running the "long" docker tests, see #293

I need to find some time to get that env working on Circle

[sparrc]

Boy, that became a doozy. I decided to eliminate docker-compose from the unit tests, instead just running the docker containers directly from the Makefile. docker-compose seems to do a lot of caching that I wasn't able to disable.

I never really liked the docker-compose requirement anyways :-)