[onecollector] Serialization fixes

[CodeBlanch]

Changes

• Change WriteDirectlyToTransportSink logic so it sends multiple requests to OneCollector until the batch is drained
• Update CommonSchemaJsonSerializer logic to drop any individual item which cannot fit into the max payload size

Details

OneCollector is strict about the amount of data it will process. Given a batch OneCollectorExporter will serialize items until it reaches the max payload size. The previous behavior was it would leave anything remaining in the batch expecting to process those records as part of the next batch. This leads to dropped telemetry though because BatchExportProcessor disposes\drains the batch after calling the exporter. The fix for this is OneCollectorExporter will now just make multiple transmissions until it has drained the batch itself. It will now also drop any single item which itself cannot fit into the max payload size.

Merge requirement checklist

• [X] CONTRIBUTING guidelines followed (license requirements, nullable enabled, static analysis, etc.)
• [X] Unit tests added/updated
• [X] Appropriate CHANGELOG.md files updated for non-trivial changes
• [ ] Changes in public API reviewed (if applicable)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 96.92308% with 2 lines in your changes missing coverage. Please review.

Project coverage is 93.22%. Comparing base (71655ce) to head (409bed9). Report is 380 commits behind head on main.

Files	Patch %	Lines
...tor/Internal/Sinks/WriteDirectlyToTransportSink.cs	95.34%	2 Missing :warning:

Additional details and impacted files

[](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry) ```diff @@ Coverage Diff @@ ## main #1999 +/- ## =========================================== + Coverage 73.91% 93.22% +19.30% =========================================== Files 267 27 -240 Lines 9615 1033 -8582 =========================================== - Hits 7107 963 -6144 + Misses 2508 70 -2438 ``` | [Flag](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry) | Coverage Δ | | |---|---|---| | [unittests-Exporter.OneCollector](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry) | `93.22% <96.92%> (?)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry#carryforward-flags-in-the-pull-request-comment) to find out more. | [Files](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry) | Coverage Δ | | |---|---|---| | [...lector/Internal/OneCollectorExporterEventSource.cs](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999?src=pr&el=tree&filepath=src%2FOpenTelemetry.Exporter.OneCollector%2FInternal%2FOneCollectorExporterEventSource.cs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry#diff-c3JjL09wZW5UZWxlbWV0cnkuRXhwb3J0ZXIuT25lQ29sbGVjdG9yL0ludGVybmFsL09uZUNvbGxlY3RvckV4cG9ydGVyRXZlbnRTb3VyY2UuY3M=) | `66.66% <100.00%> (+23.80%)` | :arrow_up: | | [...Internal/Serialization/BatchSerializationResult.cs](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999?src=pr&el=tree&filepath=src%2FOpenTelemetry.Exporter.OneCollector%2FInternal%2FSerialization%2FBatchSerializationResult.cs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry#diff-c3JjL09wZW5UZWxlbWV0cnkuRXhwb3J0ZXIuT25lQ29sbGVjdG9yL0ludGVybmFsL1NlcmlhbGl6YXRpb24vQmF0Y2hTZXJpYWxpemF0aW9uUmVzdWx0LmNz) | `100.00% <100.00%> (ø)` | | | [.../Internal/Serialization/BatchSerializationState.cs](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999?src=pr&el=tree&filepath=src%2FOpenTelemetry.Exporter.OneCollector%2FInternal%2FSerialization%2FBatchSerializationState.cs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry#diff-c3JjL09wZW5UZWxlbWV0cnkuRXhwb3J0ZXIuT25lQ29sbGVjdG9yL0ludGVybmFsL1NlcmlhbGl6YXRpb24vQmF0Y2hTZXJpYWxpemF0aW9uU3RhdGUuY3M=) | `100.00% <100.00%> (ø)` | | | [...ternal/Serialization/CommonSchemaJsonSerializer.cs](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999?src=pr&el=tree&filepath=src%2FOpenTelemetry.Exporter.OneCollector%2FInternal%2FSerialization%2FCommonSchemaJsonSerializer.cs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry#diff-c3JjL09wZW5UZWxlbWV0cnkuRXhwb3J0ZXIuT25lQ29sbGVjdG9yL0ludGVybmFsL1NlcmlhbGl6YXRpb24vQ29tbW9uU2NoZW1hSnNvblNlcmlhbGl6ZXIuY3M=) | `90.00% <100.00%> (+1.11%)` | :arrow_up: | | [...tor/Internal/Sinks/WriteDirectlyToTransportSink.cs](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999?src=pr&el=tree&filepath=src%2FOpenTelemetry.Exporter.OneCollector%2FInternal%2FSinks%2FWriteDirectlyToTransportSink.cs&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry#diff-c3JjL09wZW5UZWxlbWV0cnkuRXhwb3J0ZXIuT25lQ29sbGVjdG9yL0ludGVybmFsL1NpbmtzL1dyaXRlRGlyZWN0bHlUb1RyYW5zcG9ydFNpbmsuY3M=) | `97.33% <95.34%> (+6.19%)` | :arrow_up: | ... and [261 files with indirect coverage changes](https://app.codecov.io/gh/open-telemetry/opentelemetry-dotnet-contrib/pull/1999/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=open-telemetry)