registry

Documentation

Index

• func BuildServiceGraph(objs []interface{}, services []*Descriptor) error
• func ClearOverrides()
• func IsDisabled(srv Service) bool
• func Register(descriptor *Descriptor)
• func RegisterOverride(fn OverrideServiceFunc)
• func RegisterService(instance Service)
• func RegisterServiceWithPriority(instance Service, priority Priority)
• type BackgroundService
• type CanBeDisabled
• type DatabaseMigrator
• type Descriptor
  • func GetService(name string) *Descriptor
  • func GetServices() []*Descriptor
• type OverrideServiceFunc
• type Priority
• type Service

Functions

func BuildServiceGraph

func BuildServiceGraph(objs []interface{}, services []*Descriptor) error

BuildServiceGraph builds a graph of services and their dependencies. The services are initialized after the graph is built.

func ClearOverrides

func ClearOverrides()

func IsDisabled

func IsDisabled(srv Service) bool

IsDisabled returns whether a service is disabled.

func Register

func Register(descriptor *Descriptor)

func RegisterOverride

func RegisterOverride(fn OverrideServiceFunc)

func RegisterService

func RegisterService(instance Service)

func RegisterServiceWithPriority

func RegisterServiceWithPriority(instance Service, priority Priority)

Types

type BackgroundService

type BackgroundService interface {
	// Run starts the background process of the service after `Init` have been called
	// on all services. The `context.Context` passed into the function should be used
	// to subscribe to ctx.Done() so the service can be notified when Grafarg shuts down.
	Run(ctx context.Context) error
}

BackgroundService should be implemented for services that have long running tasks in the background.

type CanBeDisabled

type CanBeDisabled interface {
	// IsDisabled should return a bool saying if it can be started or not.
	IsDisabled() bool
}

CanBeDisabled allows the services to decide if it should be started or not by itself. This is useful for services that might not always be started, ex alerting. This will be called after `Init()`.

type DatabaseMigrator

type DatabaseMigrator interface {
	// AddMigrations allows the service to add migrations to
	// the database migrator.
	AddMigration(mg *migrator.Migrator)
}

DatabaseMigrator allows the caller to add migrations to the migrator passed as argument

type Descriptor

type Descriptor struct {
	Name         string
	Instance     Service
	InitPriority Priority
}

func GetService

func GetService(name string) *Descriptor

GetService gets the registered service descriptor with a certain name. If none is found, nil is returned.

func GetServices

func GetServices() []*Descriptor

type OverrideServiceFunc

type OverrideServiceFunc func(descriptor Descriptor) (*Descriptor, bool)

type Priority

type Priority int

const (
	High       Priority = 100
	MediumHigh Priority = 75
	Medium     Priority = 50
	Low        Priority = 0
)

type Service

type Service interface {
	// Init is called by Grafarg main process which gives the service
	// the possibility do some initial work before its started. Things
	// like adding routes, bus handlers should be done in the Init function
	Init() error
}

Service interface is the lowest common shape that services are expected to fulfill to be started within Grafarg.