Adding support for Default Haproxy Stats Page

[pasancario]

Related to #1019

[sparrc]

@pasancario you appear to have broke a unit test with this change and changed the default behavior. Can you explain why this was necessary?

[sparrc]

@pasancario I think I understand the problem now.

But how about we just change this to have users specify the full path? guessing and parsing URLs is a recipe for failure.

So rather than parsing, just have the servers list look like this:

servers = [
  "http://myhaproxy.com:1936/;csv",
  "http://anotherhaproxy.com:1936/haproxy?stats;csv"
]

[pasancario]

HI @sparrc ,

I just tried with this configuration:
servers = [ "http://myhaproxy.com:80/haproxy?stats", "http://myhaproxy.com:80/haproxy?stats;csv" ]
But it doesn't work as your are appending ;csv in final petition:
fmt.Sprintf("%s://%s%s/;csv", u.Scheme, u.Host, u.Path), nil)

I was only trying to give support to default haproxy configuration URI. We can change then URI passed by configuration file, and let haproxy plugin use it as a final request, without modifying or appending anything.

[sparrc]

@pasancario I can merge this if you make the changes to have users specify the full URL

[pasancario]

I changed it made user specify full URL, and also change default behaviour (with ;csv too)

[sparrc]

you need to run go fmt ./... on your code

[sparrc]

So what does this change for users exactly? Does the SampleConfig need to change?

Also please update the changelog

[sparrc]

@pasancario Thanks for the readme, but I meant the SampleConfig() function, this needs to change to return the correct URLs.

You'll also need to rebase because there was a separate PR for haproxy unix socket support.

[sparrc]

closing for lack of updates, @pasancario please feel free to open a new PR with your changes rebased off of master.