toggles

Documentation

Overview

Package toggles defines a standard way to define, list, and use feature toggles in the service broker.

It mimics Go's `flags` package, but uses Viper as a backing store to abstract out how a particular flag is set.

Index

• Variables
• type Toggle
  • func (toggle Toggle) EnvironmentVariable() string
  • func (toggle Toggle) IsActive() bool
• type ToggleSet
  • func NewToggleSet(propertyPrefix string) *ToggleSet
  • func (set *ToggleSet) Toggle(name string, value bool, description string) Toggle
  • func (set *ToggleSet) Toggles() []Toggle

Examples

• Toggle.EnvironmentVariable
• Toggle.IsActive
• ToggleSet.Toggles

Variables

var Compatibility = NewToggleSet("compatibility.")

Compatibility is the default set of flags for enabling compatibility modes.

var Feature = NewToggleSet("feature.")

Feature is the default set of flags for enabling or disabling features.

Types

type Toggle

type Toggle struct {
	Name        string
	Default     bool
	Description string
	// contains filtered or unexported fields
}

Toggle represents a single feature that the user can enable or disable.

func (Toggle) EnvironmentVariable

func (toggle Toggle) EnvironmentVariable() string

EnvironmentVariable gets the environment variable used to control the toggle.

Example

ts := NewToggleSet("foo.")
toggle := ts.Toggle("bar", true, "bar gets a default of true")

fmt.Println(toggle.EnvironmentVariable())

Output:

GSB_FOO_BAR

func (Toggle) IsActive

func (toggle Toggle) IsActive() bool

IsActive returns true if the toggle is enabled and false if it isn't.

Example

ts := NewToggleSet("foo.")
toggle := ts.Toggle("bar", true, "bar gets a default of true")

fmt.Println(toggle.IsActive())
viper.Set("foo.bar", "false")
defer viper.Reset()

fmt.Println(toggle.IsActive())

Output:

true
false

type ToggleSet

type ToggleSet struct {
	// contains filtered or unexported fields
}

A ToggleSet represents a set of defined toggles. The zero value of a ToggleSet has no property prefix.

func NewToggleSet

func NewToggleSet(propertyPrefix string) *ToggleSet

NewFlagSet returns a new, empty toggle set with the specified property prefix. The property prefix will be prepended to any toggles exactly as-is. You MUST specify a trailing period if you want your properties to be namespaced.

func (*ToggleSet) Toggle

func (set *ToggleSet) Toggle(name string, value bool, description string) Toggle

Toggle creates a new toggle with the given name, default value, label and description. It also adds the toggle to an internal registry and initializes the default value in viper.

func (*ToggleSet) Toggles

func (set *ToggleSet) Toggles() []Toggle

Toggles returns a list of all registered toggles sorted lexicographically by their property name.

Example

ts := NewToggleSet("foo.")

//  add some toggles
ts.Toggle("z", true, "a toggle")
ts.Toggle("a", false, "another toggle")
ts.Toggle("b", true, "a third toggle")

for _, tgl := range ts.Toggles() {
	fmt.Printf("name: %s, var: %s, description: %q, default: %v\n", tgl.Name, tgl.EnvironmentVariable(), tgl.Description, tgl.Default)
}

Output:

name: a, var: GSB_FOO_A, description: "another toggle", default: false
name: b, var: GSB_FOO_B, description: "a third toggle", default: true
name: z, var: GSB_FOO_Z, description: "a toggle", default: true