Python and FastAPI — Telemio Documentation

Install OpenTelemetry in FastAPI

Python services use the vendor-neutral OpenTelemetry SDK and exporters. Use a gateway when multiple services need policy enforcement.

Before you begin: Create a Telemio workspace and a scoped ingest credential in the console. Keep server keys in deployment secrets. Set service.name and an environment on every service, and verify signals in the console after starting the process.

Shell

pip install fastapi uvicorn opentelemetry-distro opentelemetry-exporter-otlp
opentelemetry-bootstrap -a install
export OTEL_SERVICE_NAME="recommendation-api"
export OTEL_RESOURCE_ATTRIBUTES="deployment.environment.name=production"
export OTEL_EXPORTER_OTLP_PROTOCOL="http/protobuf"
export OTEL_EXPORTER_OTLP_ENDPOINT="https://your-collector.example.com"
opentelemetry-instrument uvicorn app:app --host 0.0.0.0 --port 8000

Configure OTLP authentication on the trusted exporter or collector. Use a reachable, HTTPS endpoint and do not place credentials in the client-visible code.

Add a span for business logic

Automatic instrumentation covers inbound HTTP. Manually name domain operations for meaningful trace exploration.

Python

from fastapi import FastAPI
from opentelemetry import trace

app = FastAPI()
tracer = trace.get_tracer("recommendation-api")

@app.get("/recommendations/{category}")
def recommendations(category: str):
    with tracer.start_as_current_span("recommendations.rank") as span:
        span.set_attribute("recommendations.category", category)
        items = ["item-1", "item-2"]
        span.set_attribute("recommendations.count", len(items))
        return {"items": items}

Use the OpenTelemetry context propagators to correlate outbound HTTP calls and downstream Java or Node.js services.

Verify the trace

Run curl http://localhost:8000/recommendations/books and confirm the parent HTTP span and the ranking child span appear together.

If absent, check the Collector receiver port, protocol, authentication headers and sampling policy.