logging re-triggered on subsequent tests

[willscott]

After adding the Dash test in the performance group, I notice that logging seems to get re-added with each subsequent test.

When running ooni run performance, one sees expected output during Dash run, but then when NDT runs all log lines are duplicated, e.g.

   • Submitting test results; please be patient...
   • Submitting test results; please be patient...
   • Results successfully submitted
   • Results successfully submitted
   • OnProgress: 0.950000 - ending the test
   • OnProgress: 0.950000 - ending the test
   • Closing report; please be patient...
   • Closing report; please be patient...
   • Report successfully closed
   • Report successfully closed
   • OnProgress: 1.000000 - test complete
   • OnProgress: 1.000000 - test complete

[hellais]

Good call. The root cause of this was that the handler map was a global instead of being per nettest. To overcome this I refactored it to be instead part of the Nettest and created a NewNettest constructor. See: measurement-kit/go-measurement-kit@e6bf66a.

If you pull from the current master and run:

dep ensure -update github.com/measurement-kit/go-measurement-kit

You should find it fixed.