Split worker types

modules/worker.go

@@ -8,12 +8,13 @@ import (
 	"github.com/safing/portbase/log"
 )
 
-var (
-	serviceBackoffDuration = 2 * time.Second
+// Worker Default Configuration
+const (
+	DefaultBackoffDuration = 2 * time.Second
 )
 
-// StartWorker starts a generic worker that does not fit to be a Task or MicroTask, such as long running (and possibly mostly idle) sessions. You may declare a worker as a service, which will then be automatically restarted in case of an error.
-func (m *Module) StartWorker(name string, service bool, fn func(context.Context) error) error {
+// RunWorker directly runs a generic worker that does not fit to be a Task or MicroTask, such as long running (and possibly mostly idle) sessions. A call to RunWorker blocks until the worker is finished.
+func (m *Module) RunWorker(name string, fn func(context.Context) error) error {
 	atomic.AddInt32(m.workerCnt, 1)
 	m.waitGroup.Add(1)
 	defer func() {
@@ -21,29 +22,44 @@ func (m *Module) StartWorker(name string, service bool, fn func(context.Context)
 		m.waitGroup.Done()
 	}()
 
+	return m.runWorker(name, fn)
+}
+
+// StartServiceWorker starts a generic worker, which is automatically restarted in case of an error. A call to StartServiceWorker runs the service-worker in a new goroutine and returns immediately. `backoffDuration` specifies how to long to wait before restarts, multiplied by the number of failed attempts. Pass `0` for the default backoff duration. For custom error remediation functionality, build your own error handling procedure using calls to RunWorker.
+func (m *Module) StartServiceWorker(name string, backoffDuration time.Duration, fn func(context.Context) error) {
+	go m.runServiceWorker(name, backoffDuration, fn)
+}
+
+func (m *Module) runServiceWorker(name string, backoffDuration time.Duration, fn func(context.Context) error) {
+	atomic.AddInt32(m.workerCnt, 1)
+	m.waitGroup.Add(1)
+	defer func() {
+		atomic.AddInt32(m.workerCnt, -1)
+		m.waitGroup.Done()
+	}()
+
+	if backoffDuration == 0 {
+		backoffDuration = DefaultBackoffDuration
+	}
 	failCnt := 0
 
-	if service {
 	for {
 		if m.ShutdownInProgress() {
-				return nil
+			return
 		}
 
 		err := m.runWorker(name, fn)
 		if err != nil {
 			// log error and restart
 			failCnt++
-				sleepFor := time.Duration(failCnt) * serviceBackoffDuration
-				log.Errorf("module %s service-worker %s failed (%d): %s - restarting in %s", m.Name, name, failCnt, err, sleepFor)
+			sleepFor := time.Duration(failCnt) * backoffDuration
+			log.Errorf("%s: service-worker %s failed (%d): %s - restarting in %s", m.Name, name, failCnt, err, sleepFor)
 			time.Sleep(sleepFor)
 		} else {
-				// clean finish
-				return nil
+			// finish
+			return
 		}
 	}
-	} else {
-		return m.runWorker(name, fn)
-	}
 }
 
 func (m *Module) runWorker(name string, fn func(context.Context) error) (err error) {

modules/worker_test.go

@@ -3,6 +3,7 @@ package modules
 import (
 	"context"
 	"errors"
+	"sync"
 	"testing"
 	"time"
 )
@@ -14,7 +15,7 @@ var (
 
 func TestWorker(t *testing.T) {
 	// test basic functionality
-	err := wModule.StartWorker("test worker", false, func(ctx context.Context) error {
+	err := wModule.RunWorker("test worker", func(ctx context.Context) error {
 		return nil
 	})
 	if err != nil {
@@ -22,7 +23,7 @@ func TestWorker(t *testing.T) {
 	}
 
 	// test returning an error
-	err = wModule.StartWorker("test worker", false, func(ctx context.Context) error {
+	err = wModule.RunWorker("test worker", func(ctx context.Context) error {
 		return errTest
 	})
 	if err != errTest {
@@ -30,25 +31,26 @@ func TestWorker(t *testing.T) {
 	}
 
 	// test service functionality
-	serviceBackoffDuration = 2 * time.Millisecond // speed up backoff
 	failCnt := 0
-	err = wModule.StartWorker("test worker", true, func(ctx context.Context) error {
+	var sWTestGroup sync.WaitGroup
+	sWTestGroup.Add(1)
+	wModule.StartServiceWorker("test service-worker", 2*time.Millisecond, func(ctx context.Context) error {
 		failCnt++
 		t.Logf("service-worker test run #%d", failCnt)
 		if failCnt >= 3 {
+			sWTestGroup.Done()
 			return nil
 		}
 		return errTest
 	})
-	if err == errTest {
-		t.Errorf("service-worker failed with unexpected error: %s", err)
-	}
+	// wait for service-worker to complete test
+	sWTestGroup.Wait()
 	if failCnt != 3 {
 		t.Errorf("service-worker failed to restart")
 	}
 
 	// test panic recovery
-	err = wModule.StartWorker("test worker", false, func(ctx context.Context) error {
+	err = wModule.RunWorker("test worker", func(ctx context.Context) error {
 		var a []byte
 		_ = a[0] //nolint // we want to runtime panic!
 		return nil