Django

Learn how to instrument your Django code with OpenTelemetry.

This guide will help you instrument your Django application(s) with OpenTelemetry and send traces to Checkly.

Step 1: Install the OpenTelemetry SDK

Install the relevant OpenTelemetry packages:

Terminal

pip install opentelemetry-sdk \
  opentelemetry-exporter-otlp \
  opentelemetry-instrumentation-django \
  requests

Step 2: Initialize the instrumentation

Based on the web server you are using, you need to initialize the OpenTelemetry SDK and set up the necessary instrumentation.

Gunicorn

Open your gunicorn.config.py file and add the following code. This will initialize the OpenTelemetry SDK and set up the necessary instrumentation.

Notice the HttpHeaderSampler class. This is a custom, head-based sampler that will only sample spans that are generated by Checkly by inspecting the trace state. This way you only pay for the egress traffic generated by Checkly and not for any other traffic.

Note the code in the post_fork function. This will instrument your Django app with OpenTelemetry.

gunicorn.config.py

from opentelemetry import trace
from opentelemetry.exporter.otlp.proto.grpc.trace_exporter import OTLPSpanExporter
from opentelemetry.sdk.trace.sampling import Sampler, SamplingResult, Decision
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.instrumentation.django import DjangoInstrumentor
from requests import request

class HttpHeaderSampler(Sampler):
    def get_description(self) -> str:
        return "HttpHeaderSampler"
    def should_sample(
            parent_context, trace_id, name, kind=None, attributes=None, links=None, trace_state=None
    ) -> SamplingResult:
        if request.headers.get('tracestate') == 'checkly=true':
            return SamplingResult(Decision.RECORD_AND_SAMPLE)
        else:
            return SamplingResult(Decision.DROP )

trace.set_tracer_provider(TracerProvider(sampler=HttpHeaderSampler()))
trace.get_tracer_provider().add_span_processor(BatchSpanProcessor(OTLPSpanExporter()))

def post_fork(server, worker):
    DjangoInstrumentor().instrument(tracer_provider=trace.get_tracer_provider())

uWSGI

When using uWSGI, you can use the post_fork hook to instrument your Django app with OpenTelemetry. Note you will need to install the uwsgidecorators package.

Terminal

pip install uwsgidecorators

And then add the following code to your wsgi.py file.

wsgi.py

from uwsgidecorators import postfork
from opentelemetry import trace
from opentelemetry.exporter.otlp.proto.grpc.trace_exporter import OTLPSpanExporter
from opentelemetry.sdk.trace.sampling import Sampler, SamplingResult, Decision
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.instrumentation.django import DjangoInstrumentor
from requests import request

class HttpHeaderSampler(Sampler):
    def get_description(self) -> str:
        return "HttpHeaderSampler"
    def should_sample(
            parent_context, trace_id, name, kind=None, attributes=None, links=None, trace_state=None
    ) -> SamplingResult:
        if request.headers.get('tracestate') == 'checkly=true':
            return SamplingResult(Decision.RECORD_AND_SAMPLE)
        else:
            return SamplingResult(Decision.DROP )

trace.set_tracer_provider(TracerProvider(sampler=HttpHeaderSampler()))
trace.get_tracer_provider().add_span_processor(BatchSpanProcessor(OTLPSpanExporter()))

@postfork
def init_tracing():
    DjangoInstrumentor().instrument(tracer_provider=trace.get_tracer_provider())

Step 3: Start your app with the instrumentation

Toggle on Import Traces and grab your OTel API key in the OTel API keys section of the Traces page in the Checkly app and take a note of the endpoint for the region you want to use.

Now, export your API key in your shell by setting the OTEL_EXPORTER_OTLP_HEADERS environment variable.

export OTEL_EXPORTER_OTLP_HEADERS="authorization=<your-api-key>"

Next, export the endpoint for the region you want to use and give your service a name.

export OTEL_EXPORTER_OTLP_ENDPOINT="https://otel.eu-west-1.checklyhq.com"
export OTEL_SERVICE_NAME="your-service-name"

Then, explicitly set the protocol to use for the OTLP exporter.

export OTEL_EXPORTER_OTLP_PROTOCOL="http/protobuf"

We are using the standard OpenTelemetry environment variables here to configure the OTLP exporter.

Variable	Description
OTEL_EXPORTER_OTLP_HEADERS	The Authorization HTTP header containing your Checkly OTel API key.
OTEL_EXPORTER_OTLP_ENDPOINT	The Checkly OTel API endpoint for the region you want to use.
OTEL_EXPORTER_OTLP_PROTOCOL	The protocol to use for the OTLP exporter.
OTEL_SERVICE_NAME	The name of your service to identify it among the spans in the web UI.

Finally, start your app using the relevant command:

For Gunicorn, your startup command will look similar to

Terminal

gunicorn myapp.wsgi -c gunicorn.config.py --workers 2 --threads 2

For uWSGI, your startup command will look similar to

Terminal

uwsgi --http :8000 --wsgi-file myapp.wsgi --master --processes 4 --threads 2

🎉 You are done. Any interactions with your app that are triggered by a Checkly synthetic monitoring check will now generate traces, which are sent back to Checkly and displayed in the Checkly UI.