Configure SDK when running in Lambda environment

[srprash]

Description of changes:

The following behaviors are implemented when the ADOT Java SDK is running in a Lambda environment:

• Replace the OTLP SpanExporters (either HTTP or GRPC ones) with OtlpUdpSpanExporter to export spans to Lambda agent over UDP.
• Disable the other AWS resource providers via the otel.java.disabled.resource.providers configuration.
• Set the BSP configuration otel.bsp.max.export.batch.size to 10 for the auto-configured BatchSpanProcessor that exports the sampled spans.
• When Application Signals is enabled:
  • Export unsampled spans too via the AwsUnsampledOnlySpanProcessor. Also, setting the batch size for the AwsUnsampledOnlySpanProcessor to be 10.
  • Disable generating Application Signals metrics from the SDK.

Compare to the ADOT Python implementation: aws-observability/aws-otel-python-instrumentation#257

Testing

• The unit tests for AwsApplicationSignalsCustomizerProvider does not exist and is high effort to add it with this PR.
• Built the agent jar and tested with a simple application. Captured the debug logs from the ADOT Java agent.
  • The maxExportBatchSize is 10 for the default auto-configured BatchSpanProcessor

    spanProcessorsAll=[BatchSpanProcessor{spanExporter=software.amazon.opentelemetry.javaagent.providers.AwsMetricAttributesSpanExporter@193f604a, exportUnsampledSpans=false, scheduleDelayNanos=5000000000, maxExportBatchSize=10, exporterTimeoutNanos=30000000000}, io.opentelemetry.javaagent.tooling.AddThreadDetailsSpanProcessor@50ad3bc1, SimpleSpanProcessor{spanExporter=LoggingSpanExporter{}, exportUnsampledSpans=false}, software.amazon.opentelemetry.javaagent.providers.AttributePropagatingSpanProcessor@223aa2f7, software.amazon.opentelemetry.javaagent.providers.AwsUnsampledOnlySpanProcessor@6d3a388c]}}

  • When Application Signals is disabled, the configured exporter is still the OtlpUdpSpanExporter

    spanProcessorsAll=[BatchSpanProcessor{spanExporter=software.amazon.opentelemetry.javaagent.providers.OtlpUdpSpanExporter@394df057, exportUnsampledSpans=false, scheduleDelayNanos=5000000000, maxExportBatchSize=10, exporterTimeoutNanos=30000000000}, io.opentelemetry.javaagent.tooling.AddThreadDetailsSpanProcessor@71e9ddb4, SimpleSpanProcessor{spanExporter=LoggingSpanExporter{}, exportUnsampledSpans=false}]

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

[wangzlei]

Do we have a way to verify it? either manually or by unit test.

[srprash]

I think it can be only verified manually that the functionality works. Unit test can likely only tell if the config was set properly.

[srprash]

I will do a manual check to verify this.