Add feature flag

Author: george pogosyan

Diff for: e2e/file_es/config.yml

@@ -10,6 +10,7 @@ pipelines:
       endpoints:
         - http://localhost:9200
       fatal_on_failed_insert: true
+      split_enabled: true
       strict: false
       index_format: index_name
       retry: 1

Diff for: e2e/file_es/file_es.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"strings"
 	"testing"
 	"time"
 
@@ -35,10 +36,12 @@ func (c *Config) Configure(t *testing.T, conf *cfg.Config, pipelineName string)
 	input.Set("offsets_file", filepath.Join(offsetsDir, "offsets.yaml"))
 }
 
-const (
-	n            = 10
-	successEvent = `{"field_a":"AAAA","field_b":"BBBB"}`
-	failEvent    = `{"field_a":"AAAA","field_b":"bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"}`
+const n = 10
+
+var (
+	successEvent = `{"field_a":"AAA","field_b":"BBB"}`
+	// see ES config: http.max_content_length=128b
+	failEvent = fmt.Sprintf(`{"s":"%s"}`, strings.Repeat("#", 128))
 )
 
 func (c *Config) Send(t *testing.T) {
@@ -56,7 +59,7 @@ func (c *Config) Send(t *testing.T) {
 	err = addEvent(file, failEvent)
 	require.NoError(t, err)
 
-	for i := 0; i < 2*n-1; i++ {
+	for i := 0; i < 2*n; i++ {
 		err = addEvent(file, successEvent)
 		require.NoError(t, err)
 	}

Diff for: plugin/output/elasticsearch/README.md

@@ -133,6 +133,12 @@ After an insert error, fall with a non-zero exit code or not
 
 <br>
 
+**`split_enabled`** *`bool`* *`default=false`* 
+
+Enable split big batches
+
+<br>
+
 **`retention`** *`cfg.Duration`* *`default=1s`* 
 
 Retention milliseconds for retry to DB.

Diff for: plugin/output/elasticsearch/elasticsearch.go

@@ -42,8 +42,6 @@ type Plugin struct {
 	batcher      *pipeline.RetriableBatcher
 	avgEventSize int
 
-	begin []int
-
 	time         string
 	headerPrefix string
 	cancel       context.CancelFunc
@@ -173,6 +171,11 @@ type Config struct {
 	// > **Experimental feature**
 	FatalOnFailedInsert bool `json:"fatal_on_failed_insert" default:"false"` // *
 
+	// > @3@4@5@6
+	// >
+	// > Enable split big batches
+	SplitEnabled bool `json:"split_enabled" default:"false"` // *
+
 	// > @3@4@5@6
 	// >
 	// > Retention milliseconds for retry to DB.
@@ -202,6 +205,7 @@ type KeepAliveConfig struct {
 
 type data struct {
 	outBuf []byte
+	begin  []int
 }
 
 func init() {
@@ -223,7 +227,6 @@ func (p *Plugin) Start(config pipeline.AnyConfig, params *pipeline.OutputPluginP
 	p.registerMetrics(params.MetricCtl)
 	p.mu = &sync.Mutex{}
 	p.headerPrefix = `{"` + p.config.BatchOpType + `":{"_index":"`
-	p.begin = make([]int, 0, p.config.BatchSize_+1)
 
 	if len(p.config.IndexValues) == 0 {
 		p.config.IndexValues = append(p.config.IndexValues, "@time")
@@ -341,6 +344,7 @@ func (p *Plugin) out(workerData *pipeline.WorkerData, batch *pipeline.Batch) err
 	if *workerData == nil {
 		*workerData = &data{
 			outBuf: make([]byte, 0, p.config.BatchSize_*p.avgEventSize),
+			begin:  make([]int, 0, p.config.BatchSize_+1),
 		}
 	}
 
@@ -351,16 +355,24 @@ func (p *Plugin) out(workerData *pipeline.WorkerData, batch *pipeline.Batch) err
 	}
 
 	eventsCount := 0
-	p.begin = p.begin[:0]
+	data.begin = data.begin[:0]
 	data.outBuf = data.outBuf[:0]
 	batch.ForEach(func(event *pipeline.Event) {
 		eventsCount++
-		p.begin = append(p.begin, len(data.outBuf))
+		data.begin = append(data.begin, len(data.outBuf))
 		data.outBuf = p.appendEvent(data.outBuf, event)
 	})
-	p.begin = append(p.begin, len(data.outBuf))
+	data.begin = append(data.begin, len(data.outBuf))
+
+	var statusCode int
+	var err error
+
+	if p.config.SplitEnabled {
+		statusCode, err = p.saveOrSplit(0, eventsCount, data.begin, data.outBuf)
+	} else {
+		statusCode, err = p.save(data.outBuf)
+	}
 
-	statusCode, err := p.saveOrSplit(0, eventsCount, p.begin, data.outBuf)
 	if err != nil {
 		p.sendErrorMetric.WithLabelValues(strconv.Itoa(statusCode)).Inc()
 		switch statusCode {
@@ -381,6 +393,16 @@ func (p *Plugin) out(workerData *pipeline.WorkerData, batch *pipeline.Batch) err
 	return nil
 }
 
+func (p *Plugin) save(data []byte) (int, error) {
+	return p.client.DoTimeout(
+		http.MethodPost,
+		NDJSONContentType,
+		data,
+		p.config.ConnectionTimeout_,
+		p.reportESErrors,
+	)
+}
+
 func (p *Plugin) saveOrSplit(left int, right int, begin []int, data []byte) (int, error) {
 	if left == right {
 		return http.StatusOK, nil