BatchedDogStatsd static variables

[SamMousa]

Because the BatchedDogStatsd class uses static variables instead it is essentially a singleton.

It is not possible to have multiple instances which target different daemons or have different buffer sizes.

All variables in this class should be non-static.

[timrourke]

@SamMousa just curious - do you get any use out of BatchedDogStatsd? It's not a terrible idea in principle to give users a way to batch sends, but given the nature of PHP (not generally a long-running process), and the tiny size of this class, I wonder how much value it actually provides to users?

One could write a cleaner implementation of this "batching" behavior to suit their specific use case without a ton of trouble. Does BatchedDogStatsd earn its keep?

[SamMousa]

In the end I have written my own class that doesn't user the daemon, but instead uses the TCP endpoint directly.

Batch sending is definitely needed if you log a lot of informational messages.

[timrourke]

@SamMousa yeah I take your point, especially after writing these tests: https://github.com/DataDog/php-datadogstatsd/pull/70/files#diff-d0bbee088a9ac139cc0ce4ae6f91921bR7

Boo to static variables, they must go.