k8s.io/apiserver@v0.31.1/pkg/authorization/metrics/metrics.go (about)

     1  /*
     2  Copyright 2024 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package metrics
    18  
    19  import (
    20  	"context"
    21  	"sync"
    22  
    23  	"k8s.io/apiserver/pkg/authorization/authorizer"
    24  	"k8s.io/component-base/metrics"
    25  	"k8s.io/component-base/metrics/legacyregistry"
    26  )
    27  
    28  const (
    29  	namespace = "apiserver"
    30  	subsystem = "authorization"
    31  )
    32  
    33  var (
    34  	authorizationDecisionsTotal = metrics.NewCounterVec(
    35  		&metrics.CounterOpts{
    36  			Namespace:      namespace,
    37  			Subsystem:      subsystem,
    38  			Name:           "decisions_total",
    39  			Help:           "Total number of terminal decisions made by an authorizer split by authorizer type, name, and decision.",
    40  			StabilityLevel: metrics.ALPHA,
    41  		},
    42  		[]string{"type", "name", "decision"},
    43  	)
    44  )
    45  
    46  var registerMetrics sync.Once
    47  
    48  func RegisterMetrics() {
    49  	registerMetrics.Do(func() {
    50  		legacyregistry.MustRegister(authorizationDecisionsTotal)
    51  	})
    52  }
    53  
    54  func ResetMetricsForTest() {
    55  	authorizationDecisionsTotal.Reset()
    56  }
    57  
    58  func RecordAuthorizationDecision(authorizerType, authorizerName, decision string) {
    59  	authorizationDecisionsTotal.WithLabelValues(authorizerType, authorizerName, decision).Inc()
    60  }
    61  
    62  func InstrumentedAuthorizer(authorizerType string, authorizerName string, delegate authorizer.Authorizer) authorizer.Authorizer {
    63  	RegisterMetrics()
    64  	return &instrumentedAuthorizer{
    65  		authorizerType: string(authorizerType),
    66  		authorizerName: authorizerName,
    67  		delegate:       delegate,
    68  	}
    69  }
    70  
    71  type instrumentedAuthorizer struct {
    72  	authorizerType string
    73  	authorizerName string
    74  	delegate       authorizer.Authorizer
    75  }
    76  
    77  func (a *instrumentedAuthorizer) Authorize(ctx context.Context, attributes authorizer.Attributes) (authorizer.Decision, string, error) {
    78  	decision, reason, err := a.delegate.Authorize(ctx, attributes)
    79  	switch decision {
    80  	case authorizer.DecisionNoOpinion:
    81  		// non-terminal, not reported
    82  	case authorizer.DecisionAllow:
    83  		// matches SubjectAccessReview status.allowed field name
    84  		RecordAuthorizationDecision(a.authorizerType, a.authorizerName, "allowed")
    85  	case authorizer.DecisionDeny:
    86  		// matches SubjectAccessReview status.denied field name
    87  		RecordAuthorizationDecision(a.authorizerType, a.authorizerName, "denied")
    88  	default:
    89  		RecordAuthorizationDecision(a.authorizerType, a.authorizerName, "unknown")
    90  	}
    91  	return decision, reason, err
    92  }