rebrandly-otel 0.4.5

Python OTEL wrapper by Rebrandly

rebrandly-otel (Python)

OpenTelemetry SDK for Rebrandly Python services.

Installation

pip install rebrandly-otel

Environment Variables

Variable	Required	Description
OTEL_SERVICE_NAME	Yes	Service identifier
OTEL_SERVICE_APPLICATION	Yes	Application namespace (groups services)
OTEL_EXPORTER_OTLP_ENDPOINT	Yes	OTLP collector endpoint
OTEL_REPO_NAME	No	Repository name
OTEL_COMMIT_ID	No	Commit ID for version tracking

Lambda Handler

from rebrandly_otel import lambda_handler, logger

@lambda_handler(name="my-function")
def handler(event, context):
    logger.info("Processing", extra={"event_id": event.get("id")})
    return {"statusCode": 200}

AWS Message Handler

from rebrandly_otel import aws_message_handler

@aws_message_handler(name="process-message")
def process_record(record):
    # trace context automatically extracted from message
    return {"success": True}

Framework Middleware

Flask

from flask import Flask
from rebrandly_otel import otel, setup_flask

app = Flask(__name__)
setup_flask(otel, app)

@app.route('/api/users')
def get_users():
    return {"users": []}

FastAPI

from fastapi import FastAPI
from rebrandly_otel import otel, setup_fastapi

app = FastAPI()
setup_fastapi(otel, app)

@app.get('/api/users')
async def get_users():
    return {"users": []}

Custom Instrumentation

Manual Spans

from rebrandly_otel import otel

with otel.span("operation-name", attributes={"user.id": user_id}):
    # your code

Structured Logging

from rebrandly_otel import logger

logger.info("Order processed", extra={"order_id": order_id, "amount": amount})

HTTP Client Tracing

Using requests

from rebrandly_otel import requests_with_tracing

session = requests_with_tracing()
response = session.get('https://api.rebrandly.com/v1/links')

Using httpx

from rebrandly_otel import httpx_with_tracing

client = httpx_with_tracing()
response = client.get('https://api.rebrandly.com/v1/links')

Manual Header Injection

from rebrandly_otel import inject_traceparent

headers = {'Content-Type': 'application/json'}
inject_traceparent(headers)
# headers now includes traceparent

Custom Metrics

from rebrandly_otel import meter

# Counter
request_counter = meter.meter.create_counter(
    name='http.requests.total',
    description='Total HTTP requests'
)
request_counter.add(1, {'method': 'GET', 'endpoint': '/api/users'})

# Histogram
duration = meter.meter.create_histogram(
    name='http.request.duration',
    description='Request duration in ms',
    unit='ms'
)
duration.record(123, {'endpoint': '/api/users'})

# Gauge
gauge = meter.meter.create_gauge(
    name='queue.size',
    description='Current queue size'
)
gauge.record(42)

Database Instrumentation

PyMySQL

import pymysql
from rebrandly_otel import otel, instrument_pymysql

connection = pymysql.connect(host='localhost', user='user', password='pass', database='db')
connection = instrument_pymysql(otel, connection)

# All queries now automatically traced
with connection.cursor() as cursor:
    cursor.execute("SELECT * FROM users WHERE id = %s", (123,))

AWS Message Handling (SQS/SNS)

Sending with Trace Context

from rebrandly_otel import otel

trace_attrs = otel.tracer.get_attributes_for_aws_from_context()
sqs.send_message(QueueUrl=url, MessageBody=json.dumps(data), MessageAttributes=trace_attrs)

Receiving with Context Extraction

from rebrandly_otel import aws_message_span

with aws_message_span("process-message", message=record):
    # trace context automatically extracted

Force Flush (Critical for Lambda)

from rebrandly_otel import force_flush, shutdown

# Before Lambda exits
force_flush(timeout_millis=5000)
shutdown()

Span Status Methods

from rebrandly_otel import otel

otel.tracer.set_span_error("Operation failed")
otel.tracer.set_span_error("Failed", exception=e)
otel.tracer.set_span_success()

Cost Optimization (Errors-Only Filtering)

For high-volume services, filter out successful spans to reduce costs by 90-99%:

export OTEL_SPAN_ATTRIBUTES="span.filter=errors-only"

This adds the filter attribute to all spans. The OTEL Gateway drops successful spans while keeping all errors. Metrics are still generated from 100% of traces at the agent level.

Tips

• Always call force_flush() before Lambda exits
• Use OTEL_DEBUG=true for local debugging
• Keep metric cardinality low (< 1000 combinations)
• Add 2-3 seconds buffer to Lambda timeout for flush

Troubleshooting

No Data Exported:

• Verify OTEL_EXPORTER_OTLP_ENDPOINT is set
• Enable OTEL_DEBUG=true for console output
• Check network connectivity to collector

Missing Traces in Lambda:

• Ensure force_flush() is called before exit
• Add 2-3s buffer to Lambda timeout
• Use @lambda_handler decorator with auto_flush=True

Context Not Propagating:

• Sending: Use otel.tracer.get_attributes_for_aws_from_context() for SQS/SNS
• HTTP: Use inject_traceparent(headers) before requests
• Receiving: Use aws_message_span context manager

Best Practices

Do:

• Use context managers for spans (auto-cleanup)
• Use meaningful span names (fetch-user-profile, not handler)
• Add business context (order.id, user.id) to spans
• Flush telemetry before Lambda exits
• Use bounded attribute values in metrics

Don't:

• Store large payloads in span attributes (< 1KB)
• Use high-cardinality attributes in metrics (user_id, request_id)
• Hardcode service names (use env vars)
• Skip error recording in except blocks