Log exception when dogstatsd server fails to start. Fixes #480

[elijahandrews]

Fixes #480.

[clofresh]

This won't work in python 2.4 (which we support for the agent), you'll need to do a nested dealie of

try:
    try:
        ...
    except Exception:
        ...
finally:
   ...

Also, you probably want to reraise the exception, otherwise dogstatsd will exit with a 0 exit code instead of a 1

[elijahandrews]

Ah, thanks for pointing that out. Didn't realized that try blocks were exclusively either except or finally blocks before 2.5.

Also, wouldn't we want dogstatsd to exit with an exit code of 1 if it can't start the server, so supervisor can identify that it didn't start correctly? Or are you thinking we try to recover from an Address already in use error by starting the server on a different port.

[elijahandrews]

Just realized I misread the second part of your comment. Forget the second part of my comment above :)

[clofresh]

We do want it to exit with 1. With your new except clause though, you're catching the exception so the code will exit normally as if nothing happened. You'd want to add a raise after your log statement so that the exception bubbles up to the top level and causes an exit 1.

[clutchski]

looks good.