FastAPI

The example below is using the Python guide for OpenTelemetry (opens in a new tab).

Libraries

First, install the required dependencies.

>_ Terminal

 
pip install opentelemetry-distro opentelemetry-exporter-otlp opentelemetry-instrumentation-fastapi

Instrumentation

Method: Code changes

There are many ways to instrument your FastAPI service. The below example requires updating your code.

main.py

 
import logging
 
from fastapi import FastAPI
 
from opentelemetry.sdk.resources import SERVICE_NAME, Resource
 
from opentelemetry.trace import set_tracer_provider
from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
 
from opentelemetry._logs import set_logger_provider
from opentelemetry.sdk._logs import LoggerProvider, LoggingHandler
from opentelemetry.sdk._logs.export import BatchLogRecordProcessor
from opentelemetry.exporter.otlp.proto.http._log_exporter import  OTLPLogExporter
 
app = FastAPI()
 
logger = logging.getLogger("your-service-name")
 
resource = Resource(attributes={
    SERVICE_NAME: "your-service-name"
})
 
trace_provider = TracerProvider(resource=resource)
processor = BatchSpanProcessor(OTLPSpanExporter())
trace_provider.add_span_processor(processor)
trace.set_tracer_provider(trace_provider)
 
log_provider = LoggerProvider(resource=resource)
log_processor = BatchLogRecordProcessor(OTLPLogExporter())
log_provider.add_log_record_processor(log_processor)
set_logger_provider(log_provider)
 
logger.addHandler(LoggingHandler(logger_provider=log_provider))
 
FastAPIInstrumentor.instrument_app(app)

Method: Agent

If you prefer not to update your code, you will need to bootstrap your service.

>_ Terminal

 
opentelemetry-bootstrap -a install

Run the agent

>_ Terminal

 
opentelemetry-instrument \
    --service_name your-service-name \
    python main.py # replace with your run command

Required configuration

The following environment variables are always required.

.env

 
OTEL_EXPORTER_OTLP_ENDPOINT="https://collect.smallhours.dev/"
OTEL_EXPORTER_OTLP_HEADERS="small-hours-api-key=YOUR_API_KEY,small-hours-service-id=YOUR_SERVICE_ID"

OpenTelemetry NextJS