github.com/MetalBlockchain/metalgo@v1.11.9/api/metrics/multi_gatherer.go (about)

     1  // Copyright (C) 2019-2024, Ava Labs, Inc. All rights reserved.
     2  // See the file LICENSE for licensing terms.
     3  
     4  package metrics
     5  
     6  import (
     7  	"fmt"
     8  	"sync"
     9  
    10  	"github.com/prometheus/client_golang/prometheus"
    11  
    12  	dto "github.com/prometheus/client_model/go"
    13  )
    14  
    15  // MultiGatherer extends the Gatherer interface by allowing additional gatherers
    16  // to be registered.
    17  type MultiGatherer interface {
    18  	prometheus.Gatherer
    19  
    20  	// Register adds the outputs of [gatherer] to the results of future calls to
    21  	// Gather with the provided [name] added to the metrics.
    22  	Register(name string, gatherer prometheus.Gatherer) error
    23  }
    24  
    25  // Deprecated: Use NewPrefixGatherer instead.
    26  //
    27  // TODO: Remove once coreth is updated.
    28  func NewMultiGatherer() MultiGatherer {
    29  	return NewPrefixGatherer()
    30  }
    31  
    32  type multiGatherer struct {
    33  	lock      sync.RWMutex
    34  	names     []string
    35  	gatherers prometheus.Gatherers
    36  }
    37  
    38  func (g *multiGatherer) Gather() ([]*dto.MetricFamily, error) {
    39  	g.lock.RLock()
    40  	defer g.lock.RUnlock()
    41  
    42  	return g.gatherers.Gather()
    43  }
    44  
    45  func MakeAndRegister(gatherer MultiGatherer, name string) (*prometheus.Registry, error) {
    46  	reg := prometheus.NewRegistry()
    47  	if err := gatherer.Register(name, reg); err != nil {
    48  		return nil, fmt.Errorf("couldn't register %q metrics: %w", name, err)
    49  	}
    50  	return reg, nil
    51  }