Java worker instrumentation

[RohitRanjanMS]

• Enable the worker's capability to prevent the generation of duplicate logs. (Application Insights example in Isolated)

• Implement a Resource Detector, set resource attributes for applications running on Azure Functions. Applicable to traces and logs, but potentially metrics as well.

Attributes Description -
cloud.platform azure_functions
cloud.provider azure
cloud.resource_id /subscriptions/{subscriptionId}/resourceGroups/{groupName}/providers/Microsoft.Web/sites/{appName}
cloud.region e.g., "East US", "West Europe", etc
deployment.environment The deployment slot where the Functions App is running, such as "staging", "production", etc.

Python resource API - https://github.com/open-telemetry/opentelemetry-python/blob/main/opentelemetry-sdk/src/opentelemetry/sdk/resources/__init__.py
Example of APP Service resource detector in .Net - https://github.com/open-telemetry/opentelemetry-dotnet-contrib/tree/main/src/OpenTelemetry.ResourceDetectors.Azure

• Context Propagation : context.trace_context.Traceparent and context.trace_context.Tracestate are passed to the worker as part of the invocation request.
• Generate a span based on the context.
• Designate this span as the current one.
• Execute the customer's code within this context.
• Avoid initiating the span to prevent it from being monitored; we do not intend to export this span.
• Set the attributes like invocationid, processId and hostinstanceId.