const (
// Values for PreRelease.
Alpha = prerelease("ALPHA")
Beta = prerelease("BETA")
GA = prerelease("")
// Deprecated
Deprecated = prerelease("DEPRECATED")
)
func NewFeatureGate() *featureGate
type Feature string
FeatureGate indicates whether a given feature is enabled or not
type FeatureGate interface {
// Enabled returns true if the key is enabled.
Enabled(key Feature) bool
// KnownFeatures returns a slice of strings describing the FeatureGate's known features.
KnownFeatures() []string
// DeepCopy returns a deep copy of the FeatureGate object, such that gates can be
// set on the copy without mutating the original. This is useful for validating
// config against potential feature gate changes before committing those changes.
DeepCopy() MutableFeatureGate
}
type FeatureSpec struct {
// Default is the default enablement state for the feature
Default bool
// LockToDefault indicates that the feature is locked to its default and cannot be changed
LockToDefault bool
// PreRelease indicates the maturity level of the feature
PreRelease prerelease
}
MutableFeatureGate parses and stores flag gates for known features from a string like feature1=true,feature2=false,...
type MutableFeatureGate interface {
FeatureGate
// AddFlag adds a flag for setting global feature gates to the specified FlagSet.
AddFlag(fs *pflag.FlagSet)
// Set parses and stores flag gates for known features
// from a string like feature1=true,feature2=false,...
Set(value string) error
// SetFromMap stores flag gates for known features from a map[string]bool or returns an error
SetFromMap(m map[string]bool) error
// Add adds features to the featureGate.
Add(features map[Feature]FeatureSpec) error
// GetAll returns a copy of the map of known feature names to feature specs.
GetAll() map[Feature]FeatureSpec
// AddMetrics adds feature enablement metrics
AddMetrics()
// OverrideDefault sets a local override for the registered default value of a named
// feature. If the feature has not been previously registered (e.g. by a call to Add), has a
// locked default, or if the gate has already registered itself with a FlagSet, a non-nil
// error is returned.
//
// When two or more components consume a common feature, one component can override its
// default at runtime in order to adopt new defaults before or after the other
// components. For example, a new feature can be evaluated with a limited blast radius by
// overriding its default to true for a limited number of components without simultaneously
// changing its default for all consuming components.
OverrideDefault(name Feature, override bool) error
}