[BUG] HTTP spans have wrong parent in ApplicationInsights

[lmolkova]

Note this is likely azure-core issue, not related to storage

Describe the bug
HTTP span is reported as child of incoming request, not the logical downloadBlob in SpringBoot app

Here is the transaction

Exception or Stack Trace
N/A

To Reproduce

1. create a simple SpringBoot app
2. in the controller make a call to upload blob
3. deploy to azure app service
4. configure app insights on the app-service
5. enable Azure SDK collection

Code Snippet

	@RequestMapping("/")
		BlobClient blobClient = this.containerClient.getBlobClient("blob" + System.currentTimeMillis());
		blobClient.upload(BinaryData.fromString("test"));

		return "Greetings from Spring Boot!";
	}

Expected behavior
http span (azmondemo) should be child of upload blob span

Screenshots

Setup (please complete the following information):

• OS: Linux
• IDE: IntelliJ
• Library/Libraries: azure-core:1.17.0

Additional context

Information Checklist

• Bug Description Added
• Repro Steps Added
• Setup information Added

[lmolkova]

Investigation

All users who use agent (AppInsight or OTel) are affected

• Azure Core produces spans as expected: logical (upload blob) and physical HTTP PUT as a child
• Bytecode instrumentation agent adds another HTTP PUT span
• ApplicationInsights SDK suppresses Azure SDK Http span (which is a duplicate of the above)

Here's how it looks in Zipkin

Action items

• long term: OTel needs solution for double-instrumentation across all languages Prevent duplicate telemetry when using both library and auto instrumentation open-telemetry/opentelemetry-java-instrumentation#903
• short term: I'm looking into possible mitigation for OTel and Application Insights
• (minor) investigate span names difference (and other) between Azure SDK and agent instrumentation
• duration difference investigation: it's real, but caused by a cold start (several policies in SDK run after OTel policy and before channel handler)

/cc @trask

[lmolkova]

ApplicationInsights agent issue does not affect new agent 3.1.1+ if there is no azure-core-tracing-opentelemetry.

If user installs it AND enables otel api support, there is duplication

[lmolkova]

Fixed in OpenTelemetry Java agent v1.12.0