init: 1.0.0

pkg/service/service.go

@@ -0,0 +1,123 @@
+package service
+
+import (
+	"sync"
+
+	"github.com/perfect-panel/ppanel-server/pkg/proc"
+	"github.com/perfect-panel/ppanel-server/pkg/threading"
+)
+
+type (
+	// Starter is the interface wraps the Start method.
+	Starter interface {
+		Start()
+	}
+
+	// Stopper is the interface wraps the Stop method.
+	Stopper interface {
+		Stop()
+	}
+
+	// Service is the interface that groups Start and Stop methods.
+	Service interface {
+		Starter
+		Stopper
+	}
+
+	// Group A ServiceGroup is a group of services.
+	// Attention: the starting order of the added services is not guaranteed.
+	Group struct {
+		services []Service
+		stopOnce func()
+	}
+)
+
+// NewServiceGroup returns a ServiceGroup.
+func NewServiceGroup() *Group {
+	sg := new(Group)
+	sg.stopOnce = Once(sg.doStop)
+	return sg
+}
+
+// Add adds service into sg.
+func (sg *Group) Add(service Service) {
+	// push front, stop with reverse order.
+	sg.services = append([]Service{service}, sg.services...)
+}
+
+// Start starts the ServiceGroup.
+// There should not be any logic code after calling this method, because this method is a blocking one.
+// Also, quitting this method will close the logx output.
+func (sg *Group) Start() {
+	proc.AddShutdownListener(func() {
+		sg.stopOnce()
+	})
+
+	sg.doStart()
+}
+
+// Stop stops the ServiceGroup.
+func (sg *Group) Stop() {
+	sg.stopOnce()
+}
+
+func (sg *Group) doStart() {
+	routineGroup := threading.NewRoutineGroup()
+
+	for i := range sg.services {
+		service := sg.services[i]
+		routineGroup.Run(func() {
+			service.Start()
+		})
+	}
+
+	routineGroup.Wait()
+}
+
+func (sg *Group) doStop() {
+	for _, service := range sg.services {
+		service.Stop()
+	}
+}
+
+// WithStart wraps a start func as a Service.
+func WithStart(start func()) Service {
+	return startOnlyService{
+		start: start,
+	}
+}
+
+// WithStarter wraps a Starter as a Service.
+func WithStarter(start Starter) Service {
+	return starterOnlyService{
+		Starter: start,
+	}
+}
+
+type (
+	stopper struct{}
+
+	startOnlyService struct {
+		start func()
+		stopper
+	}
+
+	starterOnlyService struct {
+		Starter
+		stopper
+	}
+)
+
+func (s stopper) Stop() {
+}
+
+func (s startOnlyService) Start() {
+	s.start()
+}
+
+func Once(fn func()) func() {
+	once := new(sync.Once)
+	return func() {
+		once.Do(fn)
+	}
+}