not print successfully if there are Unprocessed segments

[wangzlei]

Issue #, if available:
#63

Description of changes:
If part of segments break the x-ray rules like invalid ID, at present the log is:

2020-08-11T22:59:59-07:00 [Info] Successfully sent batch of 2 segments (0.064 seconds)

This fix improves log detail, if there are Unprocessed segments returned, print:

2020-08-11T23:00:15-07:00 [Info] Sent batch of 2 segments but had 1 Unprocessed segments (0.080 seconds)

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[anuraaga]

Thanks!

[willarmiros]

Isn't this still N^2 logging? E.g. in the case of an entire batch of 50 segments being unprocessed, I believe this would still print out 52 messages/segment = 2,600 messages total.

IMO we either don't need to print out the entire batch ever, or we should just do it once outside the UnprocessedTraceSegments loop.

[wangzlei]

We just print the Unprocessed segments here, see the test result:

2020-08-11T23:00:00-07:00 [Info] Successfully sent batch of 2 segments (0.077 seconds)
2020-08-11T23:00:01-07:00 [Info] Successfully sent batch of 2 segments (0.076 seconds)
2020-08-11T23:00:02-07:00 [Info] Successfully sent batch of 2 segments (0.081 seconds)
2020-08-11T23:00:03-07:00 [Info] Successfully sent batch of 2 segments (0.066 seconds)
2020-08-11T23:00:11-07:00 [Info] Successfully sent batch of 1 segments (0.067 seconds)
2020-08-11T23:00:12-07:00 [Info] Sent batch of 2 segments but had 1 Unprocessed segments (0.088 seconds)
2020-08-11T23:00:12-07:00 [Error] Unprocessed segment: {
  ErrorCode: "InvalidId",
  Id: "0",
  Message: "Invalid segment. ErrorCode: InvalidId"
}
2020-08-11T23:00:13-07:00 [Info] Sent batch of 2 segments but had 1 Unprocessed segments (0.063 seconds)
2020-08-11T23:00:13-07:00 [Error] Unprocessed segment: {
  ErrorCode: "InvalidId",
  Id: "0",
  Message: "Invalid segment. ErrorCode: InvalidId"
}

[willarmiros]

Is debug level logging enabled in this test?

[wangzlei]

oh, will fix that in #62

[anuraaga]

This PR I think is just a small one to improve the log message (not always say Successfully), it's not a fix for the n^2 logging @willarmiros

[willarmiros]

Ah ok, was confused by the closure of #63