Alternative backends

Logfire uses the OpenTelemetry standard. This means that you can configure the SDK to export to any backend that supports OpenTelemetry.

The easiest way is to set the OTEL_EXPORTER_OTLP_ENDPOINT environment variable to a URL that points to your backend. This will be used as a base, and the SDK will append /v1/traces and /v1/metrics to the URL to send traces and metrics, respectively.

Alternatively, you can use the OTEL_EXPORTER_OTLP_TRACES_ENDPOINT and OTEL_EXPORTER_OTLP_METRICS_ENDPOINT environment variables to specify the URLs for traces and metrics separately. These URLs should include the full path, including /v1/traces and /v1/metrics.

Note

The data will be encoded using Protobuf (not JSON) and sent over HTTP (not gRPC).

Make sure that your backend supports this!

Example with Jaeger

Run this minimal command to start a Jaeger container:

docker run --rm \
  -p 16686:16686 \
  -p 4318:4318 \
  jaegertracing/all-in-one:latest

Then run this code:

import os

import logfire

# Jaeger only supports traces, not metrics, so only set the traces endpoint
# to avoid errors about failing to export metrics.
# Use port 4318 for HTTP, not 4317 for gRPC.
traces_endpoint = 'http://localhost:4318/v1/traces'
os.environ['OTEL_EXPORTER_OTLP_TRACES_ENDPOINT'] = traces_endpoint

logfire.configure(
    # Setting a service name is good practice in general, but especially
    # important for Jaeger, otherwise spans will be labeled as 'unknown_service'
    service_name='my_logfire_service',

    # Sending to Logfire is on by default regardless of the OTEL env vars.
    # Keep this line here if you don't want to send to both Jaeger and Logfire.
    send_to_logfire=False,
)

with logfire.span('This is a span'):
    logfire.info('Logfire logs are also actually just spans!')

Finally open http://localhost:16686/search?service=my_logfire_service to see the traces in the Jaeger UI.

Other environment variables

If OTEL_TRACES_EXPORTER and/or OTEL_METRICS_EXPORTER are set to any non-empty value other than otlp, then Logfire will ignore the corresponding OTEL_EXPORTER_OTLP_* variables. This is because Logfire doesn't support other exporters, so we assume that the environment variables are intended to be used by something else. Normally you don't need to worry about this, and you don't need to set these variables at all unless you want to prevent Logfire from setting up these exporters.

See the OpenTelemetry documentation for information about the other headers you can set, such as OTEL_EXPORTER_OTLP_HEADERS.