add signal 'snapshot', rename existing signal 'wakeup' to 'replication'

daemon/job/active.go

@@ -14,8 +14,8 @@ import (
 	"github.com/zrepl/zrepl/util/envconst"
 
 	"github.com/zrepl/zrepl/config"
+	"github.com/zrepl/zrepl/daemon/job/doreplication"
 	"github.com/zrepl/zrepl/daemon/job/reset"
-	"github.com/zrepl/zrepl/daemon/job/wakeup"
 	"github.com/zrepl/zrepl/daemon/pruner"
 	"github.com/zrepl/zrepl/daemon/snapper"
 	"github.com/zrepl/zrepl/endpoint"
@@ -89,7 +89,7 @@ type activeMode interface {
 	SenderReceiver() (logic.Sender, logic.Receiver)
 	Type() Type
 	PlannerPolicy() logic.PlannerPolicy
-	RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{})
+	RunPeriodic(ctx context.Context, replicationCommon chan<- struct{})
 	SnapperReport() *snapper.Report
 	ResetConnectBackoff()
 }
@@ -131,8 +131,8 @@ func (m *modePush) Type() Type { return TypePush }
 
 func (m *modePush) PlannerPolicy() logic.PlannerPolicy { return *m.plannerPolicy }
 
-func (m *modePush) RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{}) {
-	m.snapper.Run(ctx, wakeUpCommon)
+func (m *modePush) RunPeriodic(ctx context.Context, replicationCommon chan<- struct{}) {
+	m.snapper.Run(ctx, replicationCommon)
 }
 
 func (m *modePush) SnapperReport() *snapper.Report {
@@ -214,10 +214,10 @@ func (*modePull) Type() Type { return TypePull }
 
 func (m *modePull) PlannerPolicy() logic.PlannerPolicy { return *m.plannerPolicy }
 
-func (m *modePull) RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{}) {
+func (m *modePull) RunPeriodic(ctx context.Context, replicationCommon chan<- struct{}) {
 	if m.interval.Manual {
 		GetLogger(ctx).Info("manual pull configured, periodic pull disabled")
-		// "waiting for wakeups" is printed in common ActiveSide.do
+		// "waiting for wakeup replications" is printed in common ActiveSide.do
 		return
 	}
 	t := time.NewTicker(m.interval.Interval)
@@ -226,12 +226,12 @@ func (m *modePull) RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{}
 		select {
 		case <-t.C:
 			select {
-			case wakeUpCommon <- struct{}{}:
+			case replicationCommon <- struct{}{}:
 			default:
 				GetLogger(ctx).
 					WithField("pull_interval", m.interval).
 					Warn("pull job took longer than pull interval")
-				wakeUpCommon <- struct{}{} // block anyways, to queue up the wakeup
+				replicationCommon <- struct{}{} // block anyways, to queue up the wakeup replication
 			}
 		case <-ctx.Done():
 			return
@@ -435,13 +435,13 @@ func (j *ActiveSide) Run(ctx context.Context) {
 	invocationCount := 0
 outer:
 	for {
-		log.Info("wait for wakeups")
+		log.Info("wait for replications")
 		select {
 		case <-ctx.Done():
 			log.WithError(ctx.Err()).Info("context")
 			break outer
 
-		case <-wakeup.Wait(ctx):
+		case <-doreplication.Wait(ctx):
 			j.mode.ResetConnectBackoff()
 		case <-periodicDone:
 		}

daemon/job/doreplication/doreplication.go

@@ -0,0 +1,35 @@
+package doreplication
+
+import (
+	"context"
+	"errors"
+)
+
+type contextKey int
+
+const contextKeyReplication contextKey = iota
+
+func Wait(ctx context.Context) <-chan struct{} {
+	wc, ok := ctx.Value(contextKeyReplication).(chan struct{})
+	if !ok {
+		wc = make(chan struct{})
+	}
+	return wc
+}
+
+type Func func() error
+
+var AlreadyReplicating = errors.New("already replicating")
+
+func Context(ctx context.Context) (context.Context, Func) {
+	wc := make(chan struct{})
+	wuf := func() error {
+		select {
+		case wc <- struct{}{}:
+			return nil
+		default:
+			return AlreadyReplicating
+		}
+	}
+	return context.WithValue(ctx, contextKeyReplication, wc), wuf
+}

daemon/job/dosnapshot/dosnapshot.go

@@ -1,4 +1,4 @@
-package wakeup
+package dosnapshot
 
 import (
 	"context"
@@ -7,10 +7,10 @@ import (
 
 type contextKey int
 
-const contextKeyWakeup contextKey = iota
+const contextKeyDosnapshot contextKey = iota
 
 func Wait(ctx context.Context) <-chan struct{} {
-	wc, ok := ctx.Value(contextKeyWakeup).(chan struct{})
+	wc, ok := ctx.Value(contextKeyDosnapshot).(chan struct{})
 	if !ok {
 		wc = make(chan struct{})
 	}
@@ -19,7 +19,7 @@ func Wait(ctx context.Context) <-chan struct{} {
 
 type Func func() error
 
-var AlreadyWokenUp = errors.New("already woken up")
+var AlreadyDosnapshot = errors.New("already snapshotting")
 
 func Context(ctx context.Context) (context.Context, Func) {
 	wc := make(chan struct{})
@@ -28,8 +28,8 @@ func Context(ctx context.Context) (context.Context, Func) {
 		case wc <- struct{}{}:
 			return nil
 		default:
-			return AlreadyWokenUp
+			return AlreadyDosnapshot
 		}
 	}
-	return context.WithValue(ctx, contextKeyWakeup, wc), wuf
+	return context.WithValue(ctx, contextKeyDosnapshot, wc), wuf
 }

daemon/job/snapjob.go

@@ -9,12 +9,12 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 
+	"github.com/zrepl/zrepl/daemon/job/doreplication"
 	"github.com/zrepl/zrepl/daemon/logging/trace"
 	"github.com/zrepl/zrepl/util/nodefault"
 
 	"github.com/zrepl/zrepl/config"
 	"github.com/zrepl/zrepl/daemon/filters"
-	"github.com/zrepl/zrepl/daemon/job/wakeup"
 	"github.com/zrepl/zrepl/daemon/pruner"
 	"github.com/zrepl/zrepl/daemon/snapper"
 	"github.com/zrepl/zrepl/endpoint"
@@ -112,13 +112,13 @@ func (j *SnapJob) Run(ctx context.Context) {
 	invocationCount := 0
 outer:
 	for {
-		log.Info("wait for wakeups")
+		log.Info("wait for replications")
 		select {
 		case <-ctx.Done():
 			log.WithError(ctx.Err()).Info("context")
 			break outer
 
-		case <-wakeup.Wait(ctx):
+		case <-doreplication.Wait(ctx):
 		case <-periodicDone:
 		}
 		invocationCount++