github.com/grafana/pyroscope@v1.18.0/pkg/scheduler/schedulerdiscovery/config.go (about)

     1  // SPDX-License-Identifier: AGPL-3.0-only
     2  
     3  package schedulerdiscovery
     4  
     5  import (
     6  	"errors"
     7  	"flag"
     8  	"fmt"
     9  	"strings"
    10  
    11  	"github.com/go-kit/log"
    12  
    13  	"github.com/grafana/pyroscope/pkg/util"
    14  )
    15  
    16  const (
    17  	ModeFlagName = "query-scheduler.service-discovery-mode"
    18  
    19  	ModeDNS  = "dns"
    20  	ModeRing = "ring"
    21  )
    22  
    23  var modes = []string{ModeDNS, ModeRing}
    24  
    25  type Config struct {
    26  	Mode             string                `yaml:"service_discovery_mode" category:"experimental" doc:"hidden"`
    27  	SchedulerRing    util.CommonRingConfig `yaml:"ring" doc:"hidden"`
    28  	MaxUsedInstances int                   `yaml:"max_used_instances" category:"experimental"`
    29  }
    30  
    31  func (cfg *Config) RegisterFlags(f *flag.FlagSet, logger log.Logger) {
    32  	f.StringVar(&cfg.Mode, ModeFlagName, ModeDNS, fmt.Sprintf("Service discovery mode that query-frontends and queriers use to find query-scheduler instances.%s Supported values are: %s.", sharedOptionWithRingClient, strings.Join(modes, ", ")))
    33  	f.IntVar(&cfg.MaxUsedInstances, "query-scheduler.max-used-instances", 0, fmt.Sprintf("The maximum number of query-scheduler instances to use, regardless how many replicas are running. This option can be set only when -%s is set to '%s'. 0 to use all available query-scheduler instances.", ModeFlagName, ModeRing))
    34  	cfg.SchedulerRing.RegisterFlags("query-scheduler.ring.", "collectors/", ringKey, f, logger)
    35  }
    36  
    37  func (cfg *Config) Validate() error {
    38  	if !util.StringsContain(modes, cfg.Mode) {
    39  		return fmt.Errorf("unsupported query-scheduler service discovery mode (supported values are: %s)", strings.Join(modes, ", "))
    40  	}
    41  	if cfg.MaxUsedInstances > 0 && cfg.Mode != ModeRing {
    42  		return fmt.Errorf("the query-scheduler max used instances can be set only when -%s is set to '%s'", ModeFlagName, ModeRing)
    43  	}
    44  	if cfg.MaxUsedInstances < 0 {
    45  		return errors.New("the query-scheduler max used instances can't be negative")
    46  	}
    47  
    48  	return nil
    49  }