github.com/looshlee/beatles@v0.0.0-20220727174639-742810ab631c/pkg/metrics/interfaces.go (about)

     1  // Copyright 2019 Authors of Cilium
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package metrics
    16  
    17  import (
    18  	"github.com/prometheus/client_golang/prometheus"
    19  	dto "github.com/prometheus/client_model/go"
    20  )
    21  
    22  type CounterVec interface {
    23  	WithLabelValues(lvls ...string) prometheus.Counter
    24  	GetMetricWithLabelValues(lvs ...string) (prometheus.Counter, error)
    25  	With(labels prometheus.Labels) prometheus.Counter
    26  	prometheus.Collector
    27  }
    28  
    29  type GaugeVec interface {
    30  	WithLabelValues(lvls ...string) prometheus.Gauge
    31  	prometheus.Collector
    32  }
    33  
    34  var (
    35  	NoOpMetric    prometheus.Metric    = &metric{}
    36  	NoOpCollector prometheus.Collector = &collector{}
    37  
    38  	NoOpCounter     prometheus.Counter     = &counter{NoOpMetric, NoOpCollector}
    39  	NoOpCounterVec  CounterVec             = &counterVec{NoOpCollector}
    40  	NoOpObserver    prometheus.Observer    = &observer{}
    41  	NoOpObserverVec prometheus.ObserverVec = &observerVec{NoOpCollector}
    42  	NoOpGauge       prometheus.Gauge       = &gauge{NoOpMetric, NoOpCollector}
    43  	NoOpGaugeVec    GaugeVec               = &gaugeVec{NoOpCollector}
    44  )
    45  
    46  // Metric
    47  
    48  type metric struct{}
    49  
    50  // *WARNING*: Desc returns nil so do not register this metric into prometheus
    51  // default register.
    52  func (m *metric) Desc() *prometheus.Desc  { return nil }
    53  func (m *metric) Write(*dto.Metric) error { return nil }
    54  
    55  // Collector
    56  
    57  type collector struct{}
    58  
    59  func (c *collector) Describe(chan<- *prometheus.Desc) {}
    60  func (c *collector) Collect(chan<- prometheus.Metric) {}
    61  
    62  // Counter
    63  
    64  type counter struct {
    65  	prometheus.Metric
    66  	prometheus.Collector
    67  }
    68  
    69  func (cv *counter) Add(float64) {}
    70  func (cv *counter) Inc()        {}
    71  
    72  // CounterVec
    73  
    74  type counterVec struct{ prometheus.Collector }
    75  
    76  func (cv *counterVec) WithLabelValues(lvls ...string) prometheus.Counter { return NoOpCounter }
    77  
    78  func (cv *counterVec) GetMetricWithLabelValues(lvs ...string) (prometheus.Counter, error) {
    79  	return NoOpCounter, nil
    80  }
    81  
    82  func (cv *counterVec) With(labels prometheus.Labels) prometheus.Counter { return NoOpCounter }
    83  
    84  // Observer
    85  
    86  type observer struct{}
    87  
    88  func (o *observer) Observe(float64) {}
    89  
    90  // ObserverVec
    91  
    92  type observerVec struct {
    93  	prometheus.Collector
    94  }
    95  
    96  func (ov *observerVec) GetMetricWith(prometheus.Labels) (prometheus.Observer, error) {
    97  	return NoOpObserver, nil
    98  }
    99  func (ov *observerVec) GetMetricWithLabelValues(lvs ...string) (prometheus.Observer, error) {
   100  	return NoOpObserver, nil
   101  }
   102  
   103  func (ov *observerVec) With(prometheus.Labels) prometheus.Observer    { return NoOpObserver }
   104  func (ov *observerVec) WithLabelValues(...string) prometheus.Observer { return NoOpObserver }
   105  
   106  func (ov *observerVec) CurryWith(prometheus.Labels) (prometheus.ObserverVec, error) {
   107  	return NoOpObserverVec, nil
   108  }
   109  func (ov *observerVec) MustCurryWith(prometheus.Labels) prometheus.ObserverVec {
   110  	return NoOpObserverVec
   111  }
   112  
   113  // Gauge
   114  
   115  type gauge struct {
   116  	prometheus.Metric
   117  	prometheus.Collector
   118  }
   119  
   120  func (g *gauge) Set(float64)       {}
   121  func (g *gauge) Inc()              {}
   122  func (g *gauge) Dec()              {}
   123  func (g *gauge) Add(float64)       {}
   124  func (g *gauge) Sub(float64)       {}
   125  func (g *gauge) SetToCurrentTime() {}
   126  
   127  // GaugeVec
   128  
   129  type gaugeVec struct {
   130  	prometheus.Collector
   131  }
   132  
   133  func (gv *gaugeVec) WithLabelValues(lvls ...string) prometheus.Gauge {
   134  	return NoOpGauge
   135  }