diff options
Diffstat (limited to 'kube2msb/src/kube2msb/vendor/github.com/prometheus/client_golang/prometheus/collector.go')
-rw-r--r-- | kube2msb/src/kube2msb/vendor/github.com/prometheus/client_golang/prometheus/collector.go | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/kube2msb/src/kube2msb/vendor/github.com/prometheus/client_golang/prometheus/collector.go b/kube2msb/src/kube2msb/vendor/github.com/prometheus/client_golang/prometheus/collector.go new file mode 100644 index 0000000..c046880 --- /dev/null +++ b/kube2msb/src/kube2msb/vendor/github.com/prometheus/client_golang/prometheus/collector.go @@ -0,0 +1,75 @@ +// 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 + +// Collector is the interface implemented by anything that can be used by +// Prometheus to collect metrics. A Collector has to be registered for +// collection. See Register, MustRegister, RegisterOrGet, and MustRegisterOrGet. +// +// The stock metrics provided by this package (like Gauge, Counter, Summary) are +// also Collectors (which only ever collect one metric, namely itself). An +// implementer of Collector may, however, collect multiple metrics in a +// coordinated fashion and/or create metrics on the fly. Examples for collectors +// already implemented in this library are the metric vectors (i.e. collection +// of multiple instances of the same Metric but with different label values) +// like GaugeVec or SummaryVec, and the ExpvarCollector. +type Collector interface { + // Describe sends the super-set of all possible descriptors of metrics + // collected by this Collector to the provided channel and returns once + // the last descriptor has been sent. The sent descriptors fulfill the + // consistency and uniqueness requirements described in the Desc + // documentation. (It is valid if one and the same Collector sends + // duplicate descriptors. Those duplicates are simply ignored. However, + // two different Collectors must not send duplicate descriptors.) This + // method idempotently sends the same descriptors throughout the + // lifetime of the Collector. If a Collector encounters an error while + // executing this method, it must send an invalid descriptor (created + // with NewInvalidDesc) to signal the error to the registry. + Describe(chan<- *Desc) + // Collect is called by Prometheus when collecting metrics. The + // implementation sends each collected metric via the provided channel + // and returns once the last metric has been sent. The descriptor of + // each sent metric is one of those returned by Describe. Returned + // metrics that share the same descriptor must differ in their variable + // label values. This method may be called concurrently and must + // therefore be implemented in a concurrency safe way. Blocking occurs + // at the expense of total performance of rendering all registered + // metrics. Ideally, Collector implementations support concurrent + // readers. + Collect(chan<- Metric) +} + +// SelfCollector implements Collector for a single Metric so that that the +// Metric collects itself. Add it as an anonymous field to a struct that +// implements Metric, and call Init with the Metric itself as an argument. +type SelfCollector struct { + self Metric +} + +// Init provides the SelfCollector with a reference to the metric it is supposed +// to collect. It is usually called within the factory function to create a +// metric. See example. +func (c *SelfCollector) Init(self Metric) { + c.self = self +} + +// Describe implements Collector. +func (c *SelfCollector) Describe(ch chan<- *Desc) { + ch <- c.self.Desc() +} + +// Collect implements Collector. +func (c *SelfCollector) Collect(ch chan<- Metric) { + ch <- c.self +} |