# OpenTelemetry for Python on AWS Lambda

The Baselime Python OpenTelemetry tracer for AWS Lambda instruments your Python AWS Lambda functions with OpenTelemetry and automatically sends OpenTelemetry traces to Baselime. This is the most powerful and flexible way to instrument your Python AWS Lambda functions.

# Automatic Instrumentation

To automatically instrument your AWS Lambda functions with the Baselime Python OpenTelemetry tracer for AWS Lambda, set the following tag to your AWS Lambda functions: baselime:tracing=true.

For detailed instructions on how to add the tag to for your framework go to the OpenTelemetry for AWS Lambda Guide

# Adding custom OpenTelemetry spans

To add custom spans to your OpenTelemetry traces, install the opentelemetry-api package.

poetry add opentelemetry-api

And manually add spans to your traces.

from opentelemetry import trace
tracer = trace.get_tracer("your-custom-spans", "1.0.0")

def handler(event, context)
    with tracer.start_as_current_span("a-custom-span") as span:
        span.set_attribute("key", "value")
        span.set_attributes({ 'foo': 'bar'})
        span.add_event("events going down")
        try:
            json_region = os.environ['AWS_REGION']
            return {
                "statusCode": 200,
                "headers": {
                    "Content-Type": "application/json"
                },
                "body": json.dumps({
                    "Region ": json_region
                })
            }

        except Exception as e:
            span.record_exception(e)
            return {
                "statusCode": 500,
                "headers": {
                    "Content-Type": "application/json"
                },
                "body": json.dumps({
                    "Message ": "Sorry"
                })
            }