funcCollectAndCompare¶

func CollectAndCompare(cprometheus.Collector, expectedio.Reader, metricNames ...string)error

CollectAndCompare collects the metrics identified by `metricNames` and compares them in the Prometheus textexposition format to the data read from expected.

NOTE: Be mindful of accidental discrepancies between expected and metricNames; metricNames filterboth expected and collected metrics. Seehttps://github.com/prometheus/client_golang/issues/1351.

funcCollectAndCount¶added inv0.12.1

func CollectAndCount(cprometheus.Collector, metricNames ...string)int

CollectAndCount registers the provided Collector with a newly createdpedantic Registry. It then calls GatherAndCount with that Registry and withthe provided metricNames. In the unlikely case that the registration or thegathering fails, this function panics. (This is inconsistent with the otherCollectAnd… functions in this package and has historical reasons. Changingthe function signature would be a breaking change and will therefore onlyhappen with the next major version bump.)

funcCollectAndFormat¶added inv1.20.0

func CollectAndFormat(cprometheus.Collector, formatexpfmt.FormatType, metricNames ...string) ([]byte,error)

CollectAndFormat collects the metrics identified by `metricNames` and returns them in the given format.

funcCollectAndLint¶added inv0.12.1

func CollectAndLint(cprometheus.Collector, metricNames ...string) ([]promlint.Problem,error)

CollectAndLint registers the provided Collector with a newly created pedanticRegistry. It then calls GatherAndLint with that Registry and with theprovided metricNames.

funcGatherAndCompare¶

func GatherAndCompare(gprometheus.Gatherer, expectedio.Reader, metricNames ...string)error

GatherAndCompare gathers all metrics from the provided Gatherer and comparesit to an expected output read from the provided Reader in the Prometheus textexposition format. If any metricNames are provided, only metrics with thosenames are compared.

NOTE: Be mindful of accidental discrepancies between expected and metricNames; metricNames filterboth expected and gathered metrics. Seehttps://github.com/prometheus/client_golang/issues/1351.

funcGatherAndCount¶added inv0.12.1

func GatherAndCount(gprometheus.Gatherer, metricNames ...string) (int,error)

GatherAndCount gathers all metrics from the provided Gatherer and countsthem. It returns the number of metric children in all gathered metricfamilies together. If any metricNames are provided, only metrics with thosenames are counted.

funcGatherAndLint¶added inv0.12.1

func GatherAndLint(gprometheus.Gatherer, metricNames ...string) ([]promlint.Problem,error)

GatherAndLint gathers all metrics from the provided Gatherer and checks themwith the linter in the promlint package. If any metricNames are provided,only metrics with those names are checked.

funcScrapeAndCompare¶added inv1.13.0

func ScrapeAndCompare(urlstring, expectedio.Reader, metricNames ...string)error

ScrapeAndCompare calls a remote exporter's endpoint which is expected to return some metrics inplain text format. Then it compares it with the results that the `expected` would return.If the `metricNames` is not empty it would filter the comparison only to the given metric names.

NOTE: Be mindful of accidental discrepancies between expected and metricNames; metricNames filterboth expected and scraped metrics. Seehttps://github.com/prometheus/client_golang/issues/1351.

funcToFloat64¶

func ToFloat64(cprometheus.Collector)float64

ToFloat64 collects all Metrics from the provided Collector. It expects thatthis results in exactly one Metric being collected, which must be a Gauge,Counter, or Untyped. In all other cases, ToFloat64 panics. ToFloat64 returnsthe value of the collected Metric.

The Collector provided is typically a simple instance of Gauge or Counter, or– less commonly – a GaugeVec or CounterVec with exactly one element. But anyCollector fulfilling the prerequisites described above will do.

Use this function with caution. It is computationally very expensive and thusnot suited at all to read values from Metrics in regular code. This is reallyonly for testing purposes, and even for testing, other approaches are oftenmore appropriate (see this package's documentation).

A clear anti-pattern would be to use a metric type from the prometheuspackage to track values that are also needed for something else than theexposition of Prometheus metrics. For example, you would like to track thenumber of items in a queue because your code should reject queuing furtheritems if a certain limit is reached. It is tempting to track the number ofitems in a prometheus.Gauge, as it is then easily available as a metric forexposition, too. However, then you would need to call ToFloat64 in yourregular code, potentially quite often. The recommended way is to track thenumber of items conventionally (in the way you would have done it withoutconsidering Prometheus metrics) and then expose the number with aprometheus.GaugeFunc.

funcTransactionalGatherAndCompare¶added inv1.13.0

func TransactionalGatherAndCompare(gprometheus.TransactionalGatherer, expectedio.Reader, metricNames ...string)error

TransactionalGatherAndCompare gathers all metrics from the provided Gatherer and comparesit to an expected output read from the provided Reader in the Prometheus textexposition format. If any metricNames are provided, only metrics with thosenames are compared.

NOTE: Be mindful of accidental discrepancies between expected and metricNames; metricNames filterboth expected and gathered metrics. Seehttps://github.com/prometheus/client_golang/issues/1351.