application lifecycle event support

pkg/cmd/grafana-server/server.go

@@ -15,13 +15,17 @@ import (
 	"github.com/grafana/grafana/pkg/api"
 	"github.com/grafana/grafana/pkg/api/routing"
 	"github.com/grafana/grafana/pkg/bus"
+	"github.com/grafana/grafana/pkg/lifecycle"
+	"github.com/grafana/grafana/pkg/middleware"
+	"github.com/grafana/grafana/pkg/registry"
+
+	"golang.org/x/sync/errgroup"
+
+	"github.com/grafana/grafana/pkg/api"
 	"github.com/grafana/grafana/pkg/log"
-	"github.com/grafana/grafana/pkg/login"
 	"github.com/grafana/grafana/pkg/services/cache"
 	"github.com/grafana/grafana/pkg/setting"
 
-	"github.com/grafana/grafana/pkg/social"
-
 	// self registering services
 	_ "github.com/grafana/grafana/pkg/extensions"
 	_ "github.com/grafana/grafana/pkg/metrics"
@@ -35,8 +39,7 @@ import (
 	_ "github.com/grafana/grafana/pkg/services/rendering"
 	_ "github.com/grafana/grafana/pkg/services/search"
 	_ "github.com/grafana/grafana/pkg/services/sqlstore"
-	"github.com/grafana/grafana/pkg/setting"
-	"github.com/grafana/grafana/pkg/social" // self registering services
+	"github.com/grafana/grafana/pkg/setting" // self registering services
 	_ "github.com/grafana/grafana/pkg/tracing"
 	"golang.org/x/sync/errgroup"
 )
@@ -71,8 +74,7 @@ func (g *GrafanaServerImpl) Run() error {
 	g.loadConfiguration()
 	g.writePIDFile()
 
-	login.Init()
-	social.NewOAuthService()
+	lifecycle.Notify(lifecycle.ApplicationStarting)
 
 	serviceGraph := inject.Graph{}
 	serviceGraph.Provide(&inject.Object{Value: bus.GetBus()})
@@ -145,7 +147,7 @@ func (g *GrafanaServerImpl) Run() error {
 	}
 
 	sendSystemdNotification("READY=1")
-
+	lifecycle.Notify(lifecycle.ApplicationStarted)
 	return g.childRoutines.Wait()
 }
 

pkg/lifecycle/lifecycle.go

@@ -0,0 +1,22 @@
+package lifecycle
+
+type Event int
+
+const (
+	ApplicationStarting Event = iota
+	ApplicationStarted
+)
+
+type EventHandlerFunc func()
+
+var listeners = map[int][]EventHandlerFunc{}
+
+func AddListener(evt Event, fn EventHandlerFunc) {
+	listeners[int(evt)] = append(listeners[int(evt)], fn)
+}
+
+func Notify(evt Event) {
+	for _, handler := range listeners[int(evt)] {
+		handler()
+	}
+}

pkg/lifecycle/lifecycle_test.go

@@ -0,0 +1,35 @@
+package lifecycle
+
+import (
+	"testing"
+
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func TestLifecycle(t *testing.T) {
+	Convey("TestLifecycle", t, func() {
+		Convey("Given listeners", func() {
+			applicationStartingCounter := 0
+			AddListener(ApplicationStarting, func() {
+				applicationStartingCounter++
+			})
+
+			applicationStartedCounter := 0
+			AddListener(ApplicationStarted, func() {
+				applicationStartedCounter++
+			})
+
+			Convey("When notify application starting should call listener", func() {
+				Notify(ApplicationStarting)
+				So(applicationStartingCounter, ShouldEqual, 1)
+				So(applicationStartedCounter, ShouldEqual, 0)
+			})
+
+			Convey("When notify application started should call listener", func() {
+				Notify(ApplicationStarted)
+				So(applicationStartingCounter, ShouldEqual, 0)
+				So(applicationStartedCounter, ShouldEqual, 1)
+			})
+		})
+	})
+}

pkg/login/auth.go

@@ -2,7 +2,9 @@ package login
 
 import (
 	"errors"
+
 	"github.com/grafana/grafana/pkg/bus"
+	"github.com/grafana/grafana/pkg/lifecycle"
 	m "github.com/grafana/grafana/pkg/models"
 )
 
@@ -18,9 +20,11 @@ var (
 	ErrGettingUserQuota      = errors.New("Error getting user quota")
 )
 
-func Init() {
-	bus.AddHandler("auth", AuthenticateUser)
-	loadLdapConfig()
+func init() {
+	lifecycle.AddListener(lifecycle.ApplicationStarting, func() {
+		bus.AddHandler("auth", AuthenticateUser)
+		loadLdapConfig()
+	})
 }
 
 func AuthenticateUser(query *m.LoginUserQuery) error {

pkg/social/social.go

@@ -8,11 +8,18 @@ import (
 
 	"golang.org/x/oauth2"
 
+	"github.com/grafana/grafana/pkg/lifecycle"
 	"github.com/grafana/grafana/pkg/log"
 	"github.com/grafana/grafana/pkg/setting"
 	"github.com/grafana/grafana/pkg/util"
 )
 
+func init() {
+	lifecycle.AddListener(lifecycle.ApplicationStarting, func() {
+		initOAuthService()
+	})
+}
+
 type BasicUserInfo struct {
 	Id      string
 	Name    string
@@ -56,7 +63,7 @@ var (
 	allOauthes    = []string{"github", "gitlab", "google", "generic_oauth", "grafananet", grafanaCom}
 )
 
-func NewOAuthService() {
+func initOAuthService() {
 	setting.OAuthService = &setting.OAuther{}
 	setting.OAuthService.OAuthInfos = make(map[string]*setting.OAuthInfo)