[logs] Support OTel Logs Bridge API

[CodeBlanch]

The OpenTelemetry Specification has been updated with some new logging APIs marked stable:

API: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/logs/bridge-api.md
SDK: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/logs/sdk.md

This issue is for tracking the work to implement this in OTel .NET.

Note: This work has been made an experimental feature (see #4735). The APIs will be public in prerelease builds of OpenTelemetry .NET (starting with 1.6.0-alpha.1) but will be internal in stable builds.

• OpenTelemetry.Api updates
  • Initial definition: [api-logs] Add internal artifacts for OTel spec log bridge API #4422
  • Drop class InstrumentationScope: [api-logs] Remove InstrumentationScope class #4436
  • LogRecordSeverity enum: [api-logs] LogRecordSeverity enum tweaks #4451
  • Expose implementation publicly: [api-logs] Expose logging artifacts as public #4552
  • EmitLog API feedback: [api-logs] Removed default parameter from the EmitLog API #4559
• OpenTelemetry.Api.ProviderBuilderExtensions updates (DI surface)
  • Initial definition: [di-logs] Add internal artifacts for OTel spec log bridge API  #4434
  • Updates for recent changes to tracing & metrics: [di] Expose a detached LoggerProviderBuilder extension on IServiceCollection which may modify services #4531
  • Expose implementation publicly: [di-logs] Expose logging implementation as public #4558
• OpenTelemetry (SDK) updates
  • Define IServiceCollection builder: [sdk-logs] Add LoggerProviderServiceCollectionBuilder to SDK #4441
  • Define BatchExportLogRecordProcessorOptions: [sdk-logs] Add BatchExportLogRecordProcessorOptions to SDK #4446
  • Define sdk builder: [sdk-logs] Add LoggerProviderBuilderSdk to SDK #4447
  • Define builder extensions: [sdk-logs] Add LoggerProviderBuilderExtensions to SDK #4450
  • Define provider extensions: [sdk-logs] Add LoggerProvider extensions #4480
  • Define LoggerProviderSdk: [sdk-logs] Implement LoggerProviderSdk #4453
  • Define LoggerSdk: [sdk-logs] Define LoggerSdk #4455
  • LogRecord updates: [sdk-logs] Update LogRecord for Logger API additions #4456
    • Unit test: [sdk-logs] LogRecord LogLevel/Severity conversion test #4462
  • Update BatchExportLogRecordProcessorOptions for spec stable: [sdk-logs] Update the XML comments on BatchExportLogRecordProcessorOptions #4463
  • Define Sdk.CreateLoggerProviderBuilder: [sdk-logs] Add Sdk.CreateLoggerProviderBuilder #4464
  • Add tests for sdk builder extensions & provider: [sdk-logs] Tests and bug fixes for logging builder & provider #4467
  • Update ILoggerProvider to use OTel LoggerProvider: [sdk-logs] Update ILogger integration to use LoggerProvider #4473
    • New API surface for passing LoggerProvider to ILogger integration: [logging] UseOpenTelemetry extension & WithLogging default behavior #5072
      • Proposal 1: [sdk-logs] Introduce ConfigureOpenTelemetry ILoggingBuilder extension (proposal 1) #4496
      • Proposal 2: [sdk-logs] Introduce AddOpenTelemetryLogging ILoggingBuilder extension (proposal 2) #4501
      • Proposal 3: [sdk-logs] Support builder behavior on OpenTelemetryLoggerOptions (proposal 3) #4502
      • Proposal 4: [sdk-logs] Introduce OpenTelemetryLoggingBuilder (proposal 4) #4506
  • Expose implementation publicly: [sdk-logs] Expose logging SDK implementation as public #4568
  • Instrumentation scope version fix: [sdk.logs] Fix the version reported by LogRecord.Logger when using ILogger integration #4635
• OpenTelemetry.Extensions.Hosting updates
  • Define WithLogging: [hosting-logs] Add WithLogging #4483
  • Remove auto-registration of ILogger: [hosting-logs] Don't register ILogger when calling WithLogging #4535
  • Expose implementation publicly: [build] Use compiler constant to toggle experimental public apis #4735
• OpenTelemetry.Exporter.InMemory updates
  • Add LoggerProviderBuilder registration extension: [inmemory-exporter] Add extension on LoggerProviderBuilder #4541
  • Expose implementation publicly: [inmemory-logs] Expose LoggerProviderBuilder extension #4584
• OpenTelemetry.Exporter.Console updates
  • Add LoggerProviderBuilder registration extension: [console-exporter] Add extension on LoggerProviderBuilder #4549
  • Updates for LogRecord.Severity & LogRecord.SeverityText: [sdk-logs] Expose logging SDK implementation as public #4568
  • Expose implementation publicly: [console-logs] Expose LoggerProviderBuilder extension #4583
• OpenTelemetry.Exporter.OpenTelemetryProtocol.Logs updates
  • Updates for LogRecord.Severity & LogRecord.SeverityText: [sdk-logs] Expose logging SDK implementation as public #4568
  • Add LoggerProviderBuilder registration extension: Add otlp log extension methods for LoggerProviderBuilder #5103
  • Add support for Body set directly on LogRecord: [Logs Bridge API] Add support for Body set directly on LogRecord for OTLP Exporter. #5268
  • Add support for LogRecords without CategoryName set: [otlp] Use LogRecord.Logger.Name for instrumentation scope if LogRecord.CategoryName is null #5300
• Before marking stable future open/follow-up items:
  • LogRecord.Severity nullable: [sdk-logs] Update LogRecord for Logger API additions #4456 (comment)
  • Discuss obsoletions:
    • OpenTelemetryLoggerOptions.AddProcessor & OpenTelemetryLoggerOptions.SetResourceBuilder
    • InMemoryExporter, ConsoleExporter, & OtlpExporter OpenTelemetryLoggerOptions registration extensions
  • Remove added InternalsVisibleTo
    • OpenTelemetry.Api: [api-logs] Expose logging artifacts as public #4552
    • OpenTelemetry.Api.ProviderBuilderExtensions: [di-logs] Expose logging implementation as public #4558
    • OpenTelemetry: [sdk-logs] Expose logging SDK implementation as public #4568
  • Documentation updates
  • Example updates
  • Public API review

Relates to #4014

[alrz]

Is there a PR to add .WithLogging(c => c.AddOtlpExporter());? didn't find it in the list.

[cijothomas]

Is there a PR to add .WithLogging(c => c.AddOtlpExporter());? didn't find it in the list.

It is separate from Bridge itself. See #5648

[juliuskoval]

Hi, is there an ETA on when the bridge API might be stable? I'm using the API to create an NLog target (https://github.com/juliuskoval/NLog.Targets.OpenTelemetryProtocol) and it would be nice if the package didn't require pre-release versions of OpenTelemetry packages to work.