Observability

This document describes how to configure Flipt’s observability mechanisms including metrics and tracing.

Metrics

Flipt exposes Prometheus metrics at the /metrics HTTP endpoint. To see which metrics are currently supported, point your browser to FLIPT_HOST/metrics (ex: localhost:8080/metrics).

You should see a bunch of metrics being recorded such as:

flipt_cache_hit_total{cache="memory",type="flag"} 1
flipt_cache_miss_total{cache="memory",type="flag"} 1
---
go_gc_duration_seconds{quantile="0"} 8.641e-06
go_gc_duration_seconds{quantile="0.25"} 2.499e-05
go_gc_duration_seconds{quantile="0.5"} 3.5359e-05
go_gc_duration_seconds{quantile="0.75"} 6.6594e-05
go_gc_duration_seconds{quantile="1"} 0.00026651 go_gc_duration_seconds_sum
0.000402094 go_gc_duration_seconds_count 5

An example showing how to set up Flipt with Prometheus can be found in the GitHub repository.

Dashboards

We provide a set of Grafana dashboards that you can use to visualize the metrics collected by Flipt, including both server health and flag evaluation metrics.

You can find the dashboards in our grafana-dashboards repository.

Tracing

Flipt supports distributed tracing via the OpenTelemetry project.

Currently, we support the following tracing backends:

• Jaeger
• Zipkin
• OTLP.

Enable tracing via the values described in the Tracing configuration and point Flipt to your configured collector to record spans.

Examples showing how to set up Flipt with each of the supported tracing backends can be found in the main GitHub repository .

OTLP

OTLP supports additional configuration such as specifying the protocol to use (gRPC or HTTP) as well as providing custom headers to send with the request.

Custom headers can be used to provide authentication information to the collector which may be required if you are using a hosted collector such as NewRelic, DataDog, or Honeycomb.

These can be configured via the tracing.otlp configuration section.

tracing:
  otlp:
    endpoint: "https://{your-collector-url}"
    headers:
      "X-Some-Header": "some-value"