Cherry-pick #16693 to 7.x: [libbeat] [cleanup] make spool.{Spool, Settings} internal

CHANGELOG-developer.next.asciidoc

@@ -30,6 +30,7 @@ The list below covers the major changes between 7.0.0-rc2 and master only.
 - Deprecate test flags, `generate` and `update_expected`, in favor of `data`. {pull}15292[15292]
 - Python 3 is required now to run python tests and tools. {pull}14798[14798]
 - The type `memqueue.Broker` is no longer exported; instead of `memqueue.NewBroker`, call `memqueue.NewQueue` (which provides the same public interface). {pull}16667[16667]
+- The disk spool types `spool.Spool` and `spool.Settings` have been renamed to the internal types `spool.diskSpool` and `spool.settings`. {pull}16693[16693]
 - `queue.Eventer` has been renamed to `queue.ACKListener` {pull}16691[16691]
 
 ==== Bugfixes

libbeat/publisher/queue/spool/module.go

@@ -64,7 +64,7 @@ func create(
 		log = defaultLogger()
 	}
 
-	return NewSpool(log, path, Settings{
+	return newDiskSpool(log, path, settings{
 		ACKListener:       ackListener,
 		Mode:              config.File.Permissions,
 		WriteBuffer:       uint(config.Write.BufferSize),

libbeat/publisher/queue/spool/spool.go

@@ -32,8 +32,8 @@ import (
 	"github.com/elastic/go-txfile/pq"
 )
 
-// Spool implements an on-disk queue.Queue.
-type Spool struct {
+// diskSpool implements an on-disk queue.Queue.
+type diskSpool struct {
 	// producer/input support
 	inCtx    *spoolCtx
 	inBroker *inBroker
@@ -53,8 +53,8 @@ type spoolCtx struct {
 	done   chan struct{}
 }
 
-// Settings configure a new spool to be created.
-type Settings struct {
+// settings configure a new spool to be created.
+type settings struct {
 	Mode os.FileMode
 
 	File txfile.Options
@@ -76,8 +76,8 @@ type Settings struct {
 const minInFlushTimeout = 100 * time.Millisecond
 const minOutFlushTimeout = 0 * time.Millisecond
 
-// NewSpool creates and initializes a new file based queue.
-func NewSpool(logger logger, path string, settings Settings) (*Spool, error) {
+// newDiskSpool creates and initializes a new file based queue.
+func newDiskSpool(logger logger, path string, settings settings) (*diskSpool, error) {
 	mode := settings.Mode
 	if mode == 0 {
 		mode = os.ModePerm
@@ -115,7 +115,7 @@ func NewSpool(logger logger, path string, settings Settings) (*Spool, error) {
 		return nil, err
 	}
 
-	spool := &Spool{
+	spool := &diskSpool{
 		inCtx:  inCtx,
 		outCtx: outCtx,
 	}
@@ -159,7 +159,7 @@ func NewSpool(logger logger, path string, settings Settings) (*Spool, error) {
 }
 
 // Close shuts down the queue and closes the used file.
-func (s *Spool) Close() error {
+func (s *diskSpool) Close() error {
 	// stop all workers (waits for all workers to be finished)
 	s.outCtx.Close()
 	s.inCtx.Close()
@@ -174,33 +174,33 @@ func (s *Spool) Close() error {
 }
 
 // BufferConfig returns the queue initial buffer settings.
-func (s *Spool) BufferConfig() queue.BufferConfig {
+func (s *diskSpool) BufferConfig() queue.BufferConfig {
 	return queue.BufferConfig{Events: -1}
 }
 
 // Producer creates a new queue producer for publishing events.
-func (s *Spool) Producer(cfg queue.ProducerConfig) queue.Producer {
+func (s *diskSpool) Producer(cfg queue.ProducerConfig) queue.Producer {
 	return s.inBroker.Producer(cfg)
 }
 
 // Consumer creates a new queue consumer for consuming and acking events.
-func (s *Spool) Consumer() queue.Consumer {
+func (s *diskSpool) Consumer() queue.Consumer {
 	return s.outBroker.Consumer()
 }
 
 // onFlush is run whenever the queue signals it's write buffer being flushed.
 // Flush events are forwarded to all workers.
 // The onFlush callback is directly called by the queue writer (same go-routine)
 // on Write or Flush operations.
-func (s *Spool) onFlush(n uint) {
+func (s *diskSpool) onFlush(n uint) {
 	s.inBroker.onFlush(n)
 	s.outBroker.onFlush(n)
 }
 
 // onACK is run whenever the queue signals events being acked and removed from
 // the queue.
 // ACK events are forwarded to all workers.
-func (s *Spool) onACK(events, pages uint) {
+func (s *diskSpool) onACK(events, pages uint) {
 	s.inBroker.onACK(events, pages)
 }
 

libbeat/publisher/queue/spool/spool_test.go

@@ -36,7 +36,7 @@ var seed int64
 var debug bool
 
 type testQueue struct {
-	*Spool
+	*diskSpool
 	teardown func()
 }
 
@@ -104,7 +104,7 @@ func makeTestQueue(
 			logger = new(silentLogger)
 		}
 
-		spool, err := NewSpool(logger, path, Settings{
+		spool, err := newDiskSpool(logger, path, settings{
 			WriteBuffer:       writeBuffer,
 			WriteFlushTimeout: flushTimeout,
 			Codec:             codecCBORL,
@@ -119,13 +119,13 @@ func makeTestQueue(
 			t.Fatal(err)
 		}
 
-		tq := &testQueue{Spool: spool, teardown: cleanPath}
+		tq := &testQueue{diskSpool: spool, teardown: cleanPath}
 		return tq
 	}
 }
 
 func (t *testQueue) Close() error {
-	err := t.Spool.Close()
+	err := t.diskSpool.Close()
 	t.teardown()
 	return err
 }