krakend-otel/doc/TODO.md

TODO

• we are reporting the size and time in io.instruments.go as both a counter and a histogram (count can be extracted from histogram in all "backends": prometheus, datadog, new relic, etc..?)

• allow different formats for the propagation of the trace (the TextMapPropagator) in endpoint.go and in state.go.

• review how we pass the state.

• we cannot use skipPaths with the same value that we have to define the endpoints at the global layer, because we cannot know the matched pattern

• clean shutdown

• add configuration options to allow to use grpc credentials

• allow to tweak the bucket limits for different histograms (like latency and size)

  • http/client/transport_metrics.go: timeBucketsOpt, sizeBucketsOpt
  • http/server/metrics.go: timeBucketsOpt, sizeBucketsOpt
  • io/instrumens.go: timeBucketsOpt, sizeBucketsOpt
  • lura/proxy.go: timeBucketsOpt, sizeBucketsOpt

• review all metric instruments and procive the correct metric.WithUnit value.

TO DECIDE

• do we want to have the service_name to override the global ServiceConfig name for the KrakenD gateway ?

• in exporter/prometheus/prometheus.go we could add a config option that will add a prefix to all reported metrics (using the WithNamespace option).

• in lura/backend.go and lura/proxy.go we are setting the static attrs, and using semconv.ServerAddress, to set the concatenated list of hosts. Is that something that we want ?

TO CHECK

• in exporter/otelcollector/otelcollector.go, the WithEndpoint states that no http schema should be in cluded (nor path). To use http reporting methods, the WithInsecure option should be used (and to user a path WithURLPath). Check that current implementation works as expected, or fix it.

• in http/client/transport.go we have commented out the StartOptions for trace: review if would be useful to expose that in the config.

Known Issues

There is an issue, that we might have already started an span at the global layer, because we do not know if that path had to be ignored. So, at the global layer, there is no way to skip the paths