Internal Metrics Channel

[ryandotsmith]

In regards to #81, this is an implementation of an internal metrics channel. The interface looks like this:

verbose := false
mchan := metchan.New(verbose, "https://u:[email protected]/...")

func hello() {
    defer mchan.Measure("some.function", time.Now())
    return
}

This will buffer and send a complex measurement to Librato's API.

[ryandotsmith]

The metchan feature is enabled by specifying $METCHAN_URL which consequently holds the Librato URI (credentials included) for which the metchan will outlet the metrics to.

[ryandotsmith]

There is extensive GoDoc code that explains how to use this new feature from a developer's perspective.

[ryandotsmith]

This code uses its own HTTP client and is orthogonal to the librato outlet that user traffic flows though. Basically, metchan is completely isolated from normal l2met operations.

[ryandotsmith]

Going to add a few integration tests tomorrow.

[ryandotsmith]

It may be worth considering #76 with this feature. Since metchan has the ability to print the metrics to stdout, we may want to use the log package so that we can solve the problem mentioned in #76

[ryandotsmith]

I have started documenting the areas of the system which metchan is now monitoring. The docs are found in the wiki: https://github.com/ryandotsmith/l2met/wiki/Administration#monitoring