3.0.0

This major release dedicated mostly to reduce memory allocation especially while scrape collection to achieve this we made number of improvements and breaking changes.

Improvements:

• Introduced IMetricsWriter, which used to produce metric samples without creation of CMetricFamily.
• Added target to netcore2.2 which allow us to use non-allocating format methods. This dramatically reduces allocation while scrapping for application run on netcore2.2.
• ICollectorRegistry and ICollector interfaces were reviewed.
• Histogram and Summary now expose current state through Value property (which returns snapshot of the state).
• Added CounterInt64 - counter optimized for integer values. It uses atomic operations instead of optimistic lock on value increment.
• Added IValueObserver abstraction for Histogram and Summary, together with extension methods for convenient duration observation.
• All value observation methods now support explicit setting timestamp for the observation.
• Fluent syntax to register default collectors into the CollectorRegistry.
• Reviewed MetricFactory to avoid unnecessary metric creation before checking CollectorRegistry for existing one.
• Improved unit tests coverage and added benchmarks.
• Library is Strong Named now.

Breaking changes:

• Legacy .Net Framework 4.5 is not supported anymore.
• Removed PerfCounter collectors as a platform dependent feature.
• Removed all Contracts because of moving to IMetricsWriter.
• TextFormatter was removed in favor of MetricsTextWriter.
• CollectorRegistry.Instance was moved into Metrics.DefaultCollectorRegistry to isolate all static API into Metrics entry point.
• Base classes Collector and Labelled have lots of changes to correspond new API and reduce allocation.
• IOnDemandCollector was removed in favor of ICollector.
• ScrapeHandler.Process methods is async now to follow .NET Core 3.0 synchronous operations restrictions.

2.2.2

• [#35] Timestamp is in milliseconds

2.2.1

• Fix compatibility for v2.* . Use Gauge than Untyped in default metrics.

2.2.0

• [#13] Add Untyped. And use it for defaults metrics
• Rename Child -> Labelled, *.ThisChild -> .Labelled

2.1.0

• [#18] Support for timestamps in metrics
• Optimization collect metrics

2.0.0

• [#12] Remove protobuf-net and ProtoFormatter. Since prometheus 2.0 protobuf is not supported
• [#14] Change metric type names to lowercase for support prometheus 2.4.0
• Change api in ScrapeHandler, need update extensions
• Change default collectors
• Prepare for optimize code
• Move some interfaces to Prometheus.Client.Collectors.Abstractions

1.5.1

• TextFomatter: now Stream is leaveOpen

1.5.0

• Warning! Add prefix name for Contracts classes

1.4.1

• Update protobuf-net to 2.3.7

1.4.0

• Perfomance (prometheus-net/prometheus-net#68)
• Change behavior Reset() in Counter
• Refactor in Contracts