When batching, same object is mutated destroying exception information

[calleo]

While testing Azure Exporter to see if exceptions (and traces) where propagated correctly to Application Insights I noticed that stack traces ended upp in a custom field called "stacktrace" but they where not tagged as exceptions in Application Insights.

Each time an exception occurs within a span, the function span_data_to_envelope will yield twice. The problem is that the same envelope object is re-used and modified. The current tests won't fail because each yield is tested in isolation, given the nature of next.

In my setup, emit is always called with a batch of span's, meaning all of them are processed before sent to Application Insights. As a result I end up with two envelopes of type Microsoft.ApplicationInsights.Request. I would expect one of type Microsoft.ApplicationInsights.Exception and one of Microsoft.ApplicationInsights.Request.

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[lzchen]

Good catch, please fix the build errors and then we can merge this.

[calleo]

Good catch, please fix the build errors and then we can merge this.

Thanks @lzchen. Updated the way the object is copied, so hopefully works now. Had some unrelated tests fail locally (prometheus extension), but I believe something is not properly setup in my environment.

[lzchen]

@calleo
Please rebase from latest master to get the builds running :)

[lzchen]

@calleo
Would you kindly add a CHANGELOG entry?

[calleo]

@calleo Would you kindly add a CHANGELOG entry?

Thanks' for reviewing. I've added this fix to the changelog now.