Implemented batch uuids provider queue length checker

cmd/worker.go

@@ -56,9 +56,16 @@ var workerCmd = &cobra.Command{
 		handler.Handle("/healthcheck", healthcheck.Handler(
 			healthcheck.WithChecker(
 				"mojang-batch-uuids-provider-response",
-				eventsubscribers.MojangBatchUuidsProviderChecker(
+				eventsubscribers.MojangBatchUuidsProviderResponseChecker(
 					dispatcher,
-					viper.GetDuration("healthcheck.mojang_batch_uuids_provider_cool_down"),
+					viper.GetDuration("healthcheck.mojang_batch_uuids_provider_cool_down_duration"),
+				),
+			),
+			healthcheck.WithChecker(
+				"mojang-batch-uuids-provider-queue-length",
+				eventsubscribers.MojangBatchUuidsProviderQueueLengthChecker(
+					dispatcher,
+					viper.GetInt("healthcheck.mojang_batch_uuids_provider_queue_length_limit"),
 				),
 			),
 		)).Methods("GET")
@@ -84,5 +91,6 @@ var workerCmd = &cobra.Command{
 
 func init() {
 	RootCmd.AddCommand(workerCmd)
-	viper.SetDefault("healthcheck.mojang_batch_uuids_provider_cool_down", time.Minute)
+	viper.SetDefault("healthcheck.mojang_batch_uuids_provider_cool_down_duration", time.Minute)
+	viper.SetDefault("healthcheck.mojang_batch_uuids_provider_queue_length_limit", 50)
 }

eventsubscribers/health_checkers.go

@@ -2,6 +2,7 @@ package eventsubscribers
 
 import (
 	"context"
+	"errors"
 	"sync"
 	"time"
 
@@ -10,7 +11,7 @@ import (
 	"github.com/elyby/chrly/api/mojang"
 )
 
-func MojangBatchUuidsProviderChecker(dispatcher Subscriber, resetDuration time.Duration) healthcheck.CheckerFunc {
+func MojangBatchUuidsProviderResponseChecker(dispatcher Subscriber, resetDuration time.Duration) healthcheck.CheckerFunc {
 	var mutex sync.Mutex
 	var lastCallErr error
 	var expireTimer *time.Timer
@@ -40,3 +41,24 @@ func MojangBatchUuidsProviderChecker(dispatcher Subscriber, resetDuration time.D
 		return lastCallErr
 	}
 }
+
+func MojangBatchUuidsProviderQueueLengthChecker(dispatcher Subscriber, maxLength int) healthcheck.CheckerFunc {
+	var mutex sync.Mutex
+	queueLength := 0
+	dispatcher.Subscribe("mojang_textures:batch_uuids_provider:round", func(usernames []string, tasksInQueue int) {
+		mutex.Lock()
+		queueLength = tasksInQueue
+		mutex.Unlock()
+	})
+
+	return func(ctx context.Context) error {
+		mutex.Lock()
+		defer mutex.Unlock()
+
+		if queueLength < maxLength {
+			return nil
+		}
+
+		return errors.New("the maximum number of tasks in the queue has been exceeded")
+	}
+}

eventsubscribers/health_checkers_test.go

@@ -15,20 +15,20 @@ import (
 func TestMojangBatchUuidsProviderChecker(t *testing.T) {
 	t.Run("empty state", func(t *testing.T) {
 		dispatcher := bootstrap.CreateEventDispatcher()
-		checker := MojangBatchUuidsProviderChecker(dispatcher, time.Millisecond)
+		checker := MojangBatchUuidsProviderResponseChecker(dispatcher, time.Millisecond)
 		assert.Nil(t, checker(context.Background()))
 	})
 
 	t.Run("when no error occurred", func(t *testing.T) {
 		dispatcher := bootstrap.CreateEventDispatcher()
-		checker := MojangBatchUuidsProviderChecker(dispatcher, time.Millisecond)
+		checker := MojangBatchUuidsProviderResponseChecker(dispatcher, time.Millisecond)
 		dispatcher.Emit("mojang_textures:batch_uuids_provider:result", []string{"username"}, []*mojang.ProfileInfo{}, nil)
 		assert.Nil(t, checker(context.Background()))
 	})
 
 	t.Run("when error occurred", func(t *testing.T) {
 		dispatcher := bootstrap.CreateEventDispatcher()
-		checker := MojangBatchUuidsProviderChecker(dispatcher, time.Millisecond)
+		checker := MojangBatchUuidsProviderResponseChecker(dispatcher, time.Millisecond)
 		err := errors.New("some error occurred")
 		dispatcher.Emit("mojang_textures:batch_uuids_provider:result", []string{"username"}, nil, err)
 		assert.Equal(t, err, checker(context.Background()))
@@ -36,7 +36,7 @@ func TestMojangBatchUuidsProviderChecker(t *testing.T) {
 
 	t.Run("should reset value after passed duration", func(t *testing.T) {
 		dispatcher := bootstrap.CreateEventDispatcher()
-		checker := MojangBatchUuidsProviderChecker(dispatcher, 20*time.Millisecond)
+		checker := MojangBatchUuidsProviderResponseChecker(dispatcher, 20*time.Millisecond)
 		err := errors.New("some error occurred")
 		dispatcher.Emit("mojang_textures:batch_uuids_provider:result", []string{"username"}, nil, err)
 		assert.Equal(t, err, checker(context.Background()))
@@ -44,3 +44,28 @@ func TestMojangBatchUuidsProviderChecker(t *testing.T) {
 		assert.Nil(t, checker(context.Background()))
 	})
 }
+
+func TestMojangBatchUuidsProviderQueueLengthChecker(t *testing.T) {
+	t.Run("empty state", func(t *testing.T) {
+		dispatcher := bootstrap.CreateEventDispatcher()
+		checker := MojangBatchUuidsProviderQueueLengthChecker(dispatcher, 10)
+		assert.Nil(t, checker(context.Background()))
+	})
+
+	t.Run("less than allowed limit", func(t *testing.T) {
+		dispatcher := bootstrap.CreateEventDispatcher()
+		checker := MojangBatchUuidsProviderQueueLengthChecker(dispatcher, 10)
+		dispatcher.Emit("mojang_textures:batch_uuids_provider:round", []string{"username"}, 9)
+		assert.Nil(t, checker(context.Background()))
+	})
+
+	t.Run("greater than allowed limit", func(t *testing.T) {
+		dispatcher := bootstrap.CreateEventDispatcher()
+		checker := MojangBatchUuidsProviderQueueLengthChecker(dispatcher, 10)
+		dispatcher.Emit("mojang_textures:batch_uuids_provider:round", []string{"username"}, 10)
+		checkResult := checker(context.Background())
+		if assert.Error(t, checkResult) {
+			assert.Equal(t, "the maximum number of tasks in the queue has been exceeded", checkResult.Error())
+		}
+	})
+}