diff options
Diffstat (limited to 'vendor/github.com/prometheus/client_golang/prometheus/doc.go')
| -rw-r--r-- | vendor/github.com/prometheus/client_golang/prometheus/doc.go | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/doc.go b/vendor/github.com/prometheus/client_golang/prometheus/doc.go deleted file mode 100644 index 5d9525d..0000000 --- a/vendor/github.com/prometheus/client_golang/prometheus/doc.go +++ /dev/null @@ -1,201 +0,0 @@ -// Copyright 2014 The Prometheus Authors -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package prometheus is the core instrumentation package. It provides metrics -// primitives to instrument code for monitoring. It also offers a registry for -// metrics. Sub-packages allow to expose the registered metrics via HTTP -// (package promhttp) or push them to a Pushgateway (package push). There is -// also a sub-package promauto, which provides metrics constructors with -// automatic registration. -// -// All exported functions and methods are safe to be used concurrently unless -// specified otherwise. -// -// A Basic Example -// -// As a starting point, a very basic usage example: -// -// package main -// -// import ( -// "log" -// "net/http" -// -// "github.com/prometheus/client_golang/prometheus" -// "github.com/prometheus/client_golang/prometheus/promhttp" -// ) -// -// var ( -// cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{ -// Name: "cpu_temperature_celsius", -// Help: "Current temperature of the CPU.", -// }) -// hdFailures = prometheus.NewCounterVec( -// prometheus.CounterOpts{ -// Name: "hd_errors_total", -// Help: "Number of hard-disk errors.", -// }, -// []string{"device"}, -// ) -// ) -// -// func init() { -// // Metrics have to be registered to be exposed: -// prometheus.MustRegister(cpuTemp) -// prometheus.MustRegister(hdFailures) -// } -// -// func main() { -// cpuTemp.Set(65.3) -// hdFailures.With(prometheus.Labels{"device":"/dev/sda"}).Inc() -// -// // The Handler function provides a default handler to expose metrics -// // via an HTTP server. "/metrics" is the usual endpoint for that. -// http.Handle("/metrics", promhttp.Handler()) -// log.Fatal(http.ListenAndServe(":8080", nil)) -// } -// -// -// This is a complete program that exports two metrics, a Gauge and a Counter, -// the latter with a label attached to turn it into a (one-dimensional) vector. -// -// Metrics -// -// The number of exported identifiers in this package might appear a bit -// overwhelming. However, in addition to the basic plumbing shown in the example -// above, you only need to understand the different metric types and their -// vector versions for basic usage. Furthermore, if you are not concerned with -// fine-grained control of when and how to register metrics with the registry, -// have a look at the promauto package, which will effectively allow you to -// ignore registration altogether in simple cases. -// -// Above, you have already touched the Counter and the Gauge. There are two more -// advanced metric types: the Summary and Histogram. A more thorough description -// of those four metric types can be found in the Prometheus docs: -// https://prometheus.io/docs/concepts/metric_types/ -// -// A fifth "type" of metric is Untyped. It behaves like a Gauge, but signals the -// Prometheus server not to assume anything about its type. -// -// In addition to the fundamental metric types Gauge, Counter, Summary, -// Histogram, and Untyped, a very important part of the Prometheus data model is -// the partitioning of samples along dimensions called labels, which results in -// metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec, -// HistogramVec, and UntypedVec. -// -// While only the fundamental metric types implement the Metric interface, both -// the metrics and their vector versions implement the Collector interface. A -// Collector manages the collection of a number of Metrics, but for convenience, -// a Metric can also “collect itself”. Note that Gauge, Counter, Summary, -// Histogram, and Untyped are interfaces themselves while GaugeVec, CounterVec, -// SummaryVec, HistogramVec, and UntypedVec are not. -// -// To create instances of Metrics and their vector versions, you need a suitable -// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or -// UntypedOpts. -// -// Custom Collectors and constant Metrics -// -// While you could create your own implementations of Metric, most likely you -// will only ever implement the Collector interface on your own. At a first -// glance, a custom Collector seems handy to bundle Metrics for common -// registration (with the prime example of the different metric vectors above, -// which bundle all the metrics of the same name but with different labels). -// -// There is a more involved use case, too: If you already have metrics -// available, created outside of the Prometheus context, you don't need the -// interface of the various Metric types. You essentially want to mirror the -// existing numbers into Prometheus Metrics during collection. An own -// implementation of the Collector interface is perfect for that. You can create -// Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and -// NewConstSummary (and their respective Must… versions). That will happen in -// the Collect method. The Describe method has to return separate Desc -// instances, representative of the “throw-away” metrics to be created later. -// NewDesc comes in handy to create those Desc instances. Alternatively, you -// could return no Desc at all, which will marke the Collector “unchecked”. No -// checks are porformed at registration time, but metric consistency will still -// be ensured at scrape time, i.e. any inconsistencies will lead to scrape -// errors. Thus, with unchecked Collectors, the responsibility to not collect -// metrics that lead to inconsistencies in the total scrape result lies with the -// implementer of the Collector. While this is not a desirable state, it is -// sometimes necessary. The typical use case is a situatios where the exact -// metrics to be returned by a Collector cannot be predicted at registration -// time, but the implementer has sufficient knowledge of the whole system to -// guarantee metric consistency. -// -// The Collector example illustrates the use case. You can also look at the -// source code of the processCollector (mirroring process metrics), the -// goCollector (mirroring Go metrics), or the expvarCollector (mirroring expvar -// metrics) as examples that are used in this package itself. -// -// If you just need to call a function to get a single float value to collect as -// a metric, GaugeFunc, CounterFunc, or UntypedFunc might be interesting -// shortcuts. -// -// Advanced Uses of the Registry -// -// While MustRegister is the by far most common way of registering a Collector, -// sometimes you might want to handle the errors the registration might cause. -// As suggested by the name, MustRegister panics if an error occurs. With the -// Register function, the error is returned and can be handled. -// -// An error is returned if the registered Collector is incompatible or -// inconsistent with already registered metrics. The registry aims for -// consistency of the collected metrics according to the Prometheus data model. -// Inconsistencies are ideally detected at registration time, not at collect -// time. The former will usually be detected at start-up time of a program, -// while the latter will only happen at scrape time, possibly not even on the -// first scrape if the inconsistency only becomes relevant later. That is the -// main reason why a Collector and a Metric have to describe themselves to the -// registry. -// -// So far, everything we did operated on the so-called default registry, as it -// can be found in the global DefaultRegisterer variable. With NewRegistry, you -// can create a custom registry, or you can even implement the Registerer or -// Gatherer interfaces yourself. The methods Register and Unregister work in the -// same way on a custom registry as the global functions Register and Unregister -// on the default registry. -// -// There are a number of uses for custom registries: You can use registries with -// special properties, see NewPedanticRegistry. You can avoid global state, as -// it is imposed by the DefaultRegisterer. You can use multiple registries at -// the same time to expose different metrics in different ways. You can use -// separate registries for testing purposes. -// -// Also note that the DefaultRegisterer comes registered with a Collector for Go -// runtime metrics (via NewGoCollector) and a Collector for process metrics (via -// NewProcessCollector). With a custom registry, you are in control and decide -// yourself about the Collectors to register. -// -// HTTP Exposition -// -// The Registry implements the Gatherer interface. The caller of the Gather -// method can then expose the gathered metrics in some way. Usually, the metrics -// are served via HTTP on the /metrics endpoint. That's happening in the example -// above. The tools to expose metrics via HTTP are in the promhttp sub-package. -// (The top-level functions in the prometheus package are deprecated.) -// -// Pushing to the Pushgateway -// -// Function for pushing to the Pushgateway can be found in the push sub-package. -// -// Graphite Bridge -// -// Functions and examples to push metrics from a Gatherer to Graphite can be -// found in the graphite sub-package. -// -// Other Means of Exposition -// -// More ways of exposing metrics can easily be added by following the approaches -// of the existing implementations. -package prometheus |