This example shows all the code you will need to add to your index.php.
Notice the ChecklySampler 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.
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.
Next, export the endpoint for the region you want to use and give your service a name.
Then, explicitly set the protocol to use for the OTLP exporter.
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:
🎉 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.