Add Service and Environment dimensions to EMF metrics when Application Signals is enabled

[syed-ahsan-ishtiaque]

Summary

When both OTEL_AWS_APPLICATION_SIGNALS_ENABLED and
OTEL_AWS_APPLICATION_SIGNALS_EMF_EXPORT_ENABLED are true, inject
"Service" and "Environment" dimensions into EMF metrics.

• Service: extracted from resource via get_service_attribute(), falls
  back to "UnknownService"
• Environment: extracted from deployment.environment resource attribute,
  falls back to "lambda:default"
• Case-insensitive check prevents overwriting user-set dimensions
• Lambda wrapper sets OTEL_AWS_APPLICATION_SIGNALS_EMF_EXPORT_ENABLED=true
  by default

Test plan

• Unit tests added for Lambda dimension injection in test_base_emf_exporter.py
• Unit tests added for is_lambda parameter in test_console_emf_exporter.py
• Existing configurator tests updated in test_aws_opentelementry_configurator.py
• Integration tested on Lambda
• Verified EMF output contains Service and Environment dimensions
• Verified CloudWatch metrics have correct dimensions

Testing

Lambda Code

import json
import os

import boto3
import requests
from opentelemetry import metrics, trace

# Get tracer and meter
tracer = trace.get_tracer(__name__)
meter = metrics.get_meter(__name__)

# Create a counter for custom metrics
request_counter = meter.create_counter(
    "test.requests",
    unit="1",
    description="Test request counter"
)

# Initialize S3 client (outside handler for connection reuse)
s3_client = boto3.client("s3")


def lambda_handler(event, context):
    # 1. Custom span with HTTP call - generates Application Signals service metrics
    with tracer.start_as_current_span("my-custom-span") as span:
        span.set_attribute("key1", "value1")
        span.add_event("custom-event", {"detail": "something happened"})
        requests.get("https://aws.amazon.com/")

    # 2. AWS SDK call - generates Application Signals dependency metrics
    s3_client.list_buckets()

    # 3. Custom metric emission - will be converted to EMF
    request_counter.add(1, {"operation": "test"})

    return {
        "statusCode": 200,
        "body": json.dumps({
            "message": "Metrics and traces emitted",
            "function_name": os.environ.get("AWS_LAMBDA_FUNCTION_NAME"),
            "trace_id": os.environ.get("_X_AMZN_TRACE_ID")
        })
    }

CW Metrics

Application Signals Related Metrics

🤖 Generated with Claude Code