prometheus/client_model

_(If you are reading this because you are interested in Prometheus's native histograms, pay special attention to the last paragraph below.)_ # Deprecation note This repository used to contain the [protocol buffer](https://developers.google.com/protocol-buffers) code that defined both the data model and the exposition format of Prometheus metrics. Starting with v2.0.0, the [Prometheus server](https://github.com/prometheus/prometheus) does not ingest the protobuf-based exposition format anymore. Currently, all but one of the [official instrumentation libraries](https://prometheus.io/docs/instrumenting/clientlibs/) do not expose the protobuf-based exposition format. The [Go instrumentation library](https://github.com/prometheus/client_golang), however, has been built around the protobuf-based data model. As a byproduct thereof, it is still able to expose the protobuf-based exposition format. The Go instrumentation library is the only remaining repository within the [Prometheus GitHub org](https://github.com/prometheus) directly using the prometheus/client_model repository. Check out the [OpenMetrics project](https://openmetrics.io/) for the future of the data model and exposition format used by Prometheus and others. Note, though, that in an ironic twist of fate, the protobuf-based exposition format got revived to suppert native histograms in Prometheus. Therefore, starting with v2.40.0, the Prometheus server is again capable of ingesting the protobuf-based exposition format. Eventually, native histogram support will be added in some form to OpenMetrics, too.