Queue: Make WorkerPools and Queues flushable (#10001)

* Make WorkerPools and Queues flushable

Adds Flush methods to Queues and the WorkerPool
Further abstracts the WorkerPool
Adds a final step to Flush the queues in the defer from PrintCurrentTest
Fixes an issue with Settings inheritance in queues

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Change to for loop

* Add IsEmpty and begin just making the queues composed WorkerPools

* subsume workerpool into the queues and create a flushable interface

* Add manager command

* Move flushall to queue.Manager and add to testlogger

* As per @guillep2k

* as per @guillep2k

* Just make queues all implement flushable and clean up the wrapped queue flushes

* cope with no timeout

Co-authored-by: Lauris BH <lauris@nix.lv>

modules/queue/queue_channel_test.go

@@ -25,12 +25,14 @@ func TestChannelQueue(t *testing.T) {
 
 	queue, err := NewChannelQueue(handle,
 		ChannelQueueConfiguration{
-			QueueLength:  20,
-			Workers:      1,
-			MaxWorkers:   10,
-			BlockTimeout: 1 * time.Second,
-			BoostTimeout: 5 * time.Minute,
-			BoostWorkers: 5,
+			WorkerPoolConfiguration: WorkerPoolConfiguration{
+				QueueLength:  20,
+				MaxWorkers:   10,
+				BlockTimeout: 1 * time.Second,
+				BoostTimeout: 5 * time.Minute,
+				BoostWorkers: 5,
+			},
+			Workers: 1,
 		}, &testData{})
 	assert.NoError(t, err)
 
@@ -60,13 +62,15 @@ func TestChannelQueue_Batch(t *testing.T) {
 
 	queue, err := NewChannelQueue(handle,
 		ChannelQueueConfiguration{
-			QueueLength:  20,
-			BatchLength:  2,
-			Workers:      1,
-			MaxWorkers:   10,
-			BlockTimeout: 1 * time.Second,
-			BoostTimeout: 5 * time.Minute,
-			BoostWorkers: 5,
+			WorkerPoolConfiguration: WorkerPoolConfiguration{
+				QueueLength:  20,
+				BatchLength:  2,
+				BlockTimeout: 1 * time.Second,
+				BoostTimeout: 5 * time.Minute,
+				BoostWorkers: 5,
+				MaxWorkers:   10,
+			},
+			Workers: 1,
 		}, &testData{})
 	assert.NoError(t, err)