tendermint: github.com/tendermint/tendermint/libs/service Index | Files

package service

import "github.com/tendermint/tendermint/libs/service"

Index

Package Files

service.go

Variables

var (
    // ErrAlreadyStarted is returned when somebody tries to start an already
    // running service.
    ErrAlreadyStarted = errors.New("already started")
    // ErrAlreadyStopped is returned when somebody tries to stop an already
    // stopped service (without resetting it).
    ErrAlreadyStopped = errors.New("already stopped")
    // ErrNotStarted is returned when somebody tries to stop a not running
    // service.
    ErrNotStarted = errors.New("not started")
)

type BaseService Uses

type BaseService struct {
    Logger log.Logger
    // contains filtered or unexported fields
}

Classical-inheritance-style service declarations. Services can be started, then stopped, then optionally restarted.

Users can override the OnStart/OnStop methods. In the absence of errors, these methods are guaranteed to be called at most once. If OnStart returns an error, service won't be marked as started, so the user can call Start again.

A call to Reset will panic, unless OnReset is overwritten, allowing OnStart/OnStop to be called again.

The caller must ensure that Start and Stop are not called concurrently.

It is ok to call Stop without calling Start first.

Typical usage:

type FooService struct {
	BaseService
	// private fields
}

func NewFooService() *FooService {
	fs := &FooService{
		// init
	}
	fs.BaseService = *NewBaseService(log, "FooService", fs)
	return fs
}

func (fs *FooService) OnStart() error {
	fs.BaseService.OnStart() // Always call the overridden method.
	// initialize private fields
	// start subroutines, etc.
}

func (fs *FooService) OnStop() error {
	fs.BaseService.OnStop() // Always call the overridden method.
	// close/destroy private fields
	// stop subroutines, etc.
}

func NewBaseService Uses

func NewBaseService(logger log.Logger, name string, impl Service) *BaseService

NewBaseService creates a new BaseService.

func (*BaseService) IsRunning Uses

func (bs *BaseService) IsRunning() bool

IsRunning implements Service by returning true or false depending on the service's state.

func (*BaseService) OnReset Uses

func (bs *BaseService) OnReset() error

OnReset implements Service by panicking.

func (*BaseService) OnStart Uses

func (bs *BaseService) OnStart() error

OnStart implements Service by doing nothing. NOTE: Do not put anything in here, that way users don't need to call BaseService.OnStart()

func (*BaseService) OnStop Uses

func (bs *BaseService) OnStop()

OnStop implements Service by doing nothing. NOTE: Do not put anything in here, that way users don't need to call BaseService.OnStop()

func (*BaseService) Quit Uses

func (bs *BaseService) Quit() <-chan struct{}

Quit Implements Service by returning a quit channel.

func (*BaseService) Reset Uses

func (bs *BaseService) Reset() error

Reset implements Service by calling OnReset callback (if defined). An error will be returned if the service is running.

func (*BaseService) SetLogger Uses

func (bs *BaseService) SetLogger(l log.Logger)

SetLogger implements Service by setting a logger.

func (*BaseService) Start Uses

func (bs *BaseService) Start() error

Start implements Service by calling OnStart (if defined). An error will be returned if the service is already running or stopped. Not to start the stopped service, you need to call Reset.

func (*BaseService) Stop Uses

func (bs *BaseService) Stop() error

Stop implements Service by calling OnStop (if defined) and closing quit channel. An error will be returned if the service is already stopped.

func (*BaseService) String Uses

func (bs *BaseService) String() string

String implements Service by returning a string representation of the service.

func (*BaseService) Wait Uses

func (bs *BaseService) Wait()

Wait blocks until the service is stopped.

type Service Uses

type Service interface {
    // Start the service.
    // If it's already started or stopped, will return an error.
    // If OnStart() returns an error, it's returned by Start()
    Start() error
    OnStart() error

    // Stop the service.
    // If it's already stopped, will return an error.
    // OnStop must never error.
    Stop() error
    OnStop()

    // Reset the service.
    // Panics by default - must be overwritten to enable reset.
    Reset() error
    OnReset() error

    // Return true if the service is running
    IsRunning() bool

    // Quit returns a channel, which is closed once service is stopped.
    Quit() <-chan struct{}

    // String representation of the service
    String() string

    // SetLogger sets a logger.
    SetLogger(log.Logger)
}

Service defines a service that can be started, stopped, and reset.

Package service imports 4 packages (graph) and is imported by 36 packages. Updated 2020-07-02. Refresh now. Tools for package owners.