[SVLS-8179] add debug log for flush strategy

[jchrostek-dd]

Overview

• Add debug log for flush strategy.
• Add debug log for incoming telemetry records. This excludes Extension telemetry since that would lead to an infinite loop.

Testing

• Deployed and invoked function. Confirm we see flush strategy and incoming telemetry records.

[lym953]

We are already logging telemetry events here:

datadog-lambda-extension/bottlecap/src/bin/bottlecap/main.rs

Line 1213 in 57315b8

debug!("Telemetry event received: {:?}", event);

Is the new log added to help debug what happens in between?

[jchrostek-dd]

Yeah, helpful for what happens in between. When I was looking at logs for Durable Functions, it seemed like we were missing some things.

[astuyve]

We should probably revert this. If we’re missing something for durable functions then let’s find out why it’s not being captured and sent to Datadog or via a Datadog flare. This will cause us to double log everything the user sends if debug logs are enabled, which will more than 2x the cost for no value.