implement context cancellation on db error

pkg/file/file.go

@@ -7,7 +7,6 @@ import (
 	"io"
 	"log"
 	"os"
-	"time"
 
 	"git.k-space.ee/k-space/logmower-shipper/pkg/globals"
 	"git.k-space.ee/k-space/logmower-shipper/pkg/lines"
@@ -29,20 +28,8 @@ type File struct {
 
 // TODO: caller could call duplicate shipFile of same name on file replace: sends might not work properly
 func (f File) Process(ctx context.Context, db *mongo.Collection, recordLimitBytes int) {
-	lineChan := make(chan lines.Raw)
-	defer close(lineChan)
-
-	dbQueue := make(chan m.Record, SendQueueLimit)
-	go lines.RawC(lineChan).Process(recordLimitBytes, dbQueue)
-
-	waitGo := util.GoWg(func() {
-		sender.Queue(dbQueue).Sender(db, f.MetricsName)
-	})
-	defer waitGo()
-
-	// TODO: better way to kill or wait for sendQueue before retrying (or duplicates?)
 	_ = wait.ManagedExponentialBackoffWithContext(ctx, globals.Backoff(), func() (done bool, _ error) {
-		err := f.trySubmit(ctx, db, lineChan)
+		err := f.process(ctx, db, recordLimitBytes)
 		if err == nil {
 			return true, nil
 		}
@@ -55,20 +42,39 @@ func (f File) Process(ctx context.Context, db *mongo.Collection, recordLimitByte
 	})
 }
 
-// use submitter(), don't use directly
+func (f File) launchChannels(cancel func(), db *mongo.Collection, recordLimitBytes int) (_ chan<- lines.Raw, deferFn func()) {
-func (f File) trySubmit(ctx context.Context, db *mongo.Collection, sendQueue chan<- lines.Raw) error {
+	lineOut := make(chan lines.Raw)
-	lFile := lines.File(f) // file.File, but avoiding import cycle
 
-	// TODO: better way for respecting ?killing sender for retry
+	sctx, scancel := context.WithCancel(context.Background())
-	for {
+	cancelAll := func() {
-		if len(sendQueue) == 0 {
+		cancel()
-			break
+		scancel()
-		}
-		time.Sleep(time.Second)
 	}
 
+	dbQueue := make(chan m.Record, SendQueueLimit)
+	go lines.RawC(lineOut).Process(sctx, recordLimitBytes, dbQueue)
+
+	waitBatchSend := util.GoWg(func() {
+		sender.Queue(dbQueue).Sender(db, f.MetricsName, cancelAll)
+	})
+
+	return lineOut, func() {
+		close(lineOut)
+		waitBatchSend()
+	}
+}
+
+// use submitter(), don't use directly
+func (f File) process(ctx context.Context, db *mongo.Collection, recordLimitBytes int) error {
+	lFile := lines.File(f) // file.File, but avoiding import cycle
+
+	sctx, cancel := context.WithCancel(ctx)
+
+	lineOut, dfn := f.launchChannels(cancel, db, recordLimitBytes)
+	defer dfn()
+
 	// get files with offset
-	offsetResult, _ := mongoWithErr(db.FindOne(globals.MongoTimeout(ctx),
+	offsetResult, _ := mongoWithErr(db.FindOne(globals.MongoTimeout(sctx),
 		bson.D{{Key: m.RecordKeyHostId, Value: f.Host.Id}, {Key: m.RecordKeyFilePath, Value: f.Path}},
 		&mongoOpt.FindOneOptions{Sort: bson.D{{Key: m.RecordKeyOffset, Value: -1}}}, // sort descending (get largest)
 	))
@@ -77,24 +83,20 @@ func (f File) trySubmit(ctx context.Context, db *mongo.Collection, sendQueue cha
 	if err != nil && !errors.Is(err, mongo.ErrNoDocuments) {
 		return fmt.Errorf("retrieving offset from database: %w", err)
 	}
-
 	dbOffset := m.RecordOffsetFromBson(&offsetResultBytes)
 
+	// for promFileChatcupDone
 	fi, err := os.Stat(f.Path)
 	if err != nil {
 		return fmt.Errorf("getting original file size: %w", err)
 	}
 	startSize := fi.Size()
 
-	sctx, cancel := context.WithCancel(ctx)
+	lineIn, errChan, err := util.TailFile(sctx, f.Path, dbOffset, io.SeekStart)
-	defer cancel()
-
-	promFileInitialSeekSkipped.WithLabelValues(f.MetricsName).Set(float64(dbOffset))
-
-	lineChan, errChan, err := util.TailFile(sctx, f.Path, dbOffset, io.SeekStart)
 	if err != nil {
 		return fmt.Errorf("tailing file: %w", err)
 	}
+	promFileInitialSeekSkipped.WithLabelValues(f.MetricsName).Set(float64(dbOffset))
 
 	var catchUpped bool
 	promFileCatchupDone.WithLabelValues(f.MetricsName).Set(0)
@@ -104,7 +106,7 @@ func (f File) trySubmit(ctx context.Context, db *mongo.Collection, sendQueue cha
 		case err := <-errChan:
 			return fmt.Errorf("tailing file: %w", err)
 
-		case line, ok := <-lineChan:
+		case line, ok := <-lineIn:
 			if !ok {
 				return nil
 			}
@@ -123,11 +125,15 @@ func (f File) trySubmit(ctx context.Context, db *mongo.Collection, sendQueue cha
 				continue
 			}
 
-			sendQueue <- lines.Raw{
+			select {
+			case <-sctx.Done():
+
+			case lineOut <- lines.Raw{
 				File: &lFile,
 
 				Offset: line.EndOffset,
 				B:      line.Bytes,
+			}:
 			}
 		}
 	}

pkg/lines/lines.go

@@ -1,6 +1,7 @@
 package lines
 
 import (
+	"context"
 	"log"
 	"sync"
 
@@ -23,7 +24,7 @@ type (
 )
 
 // assumes all lines are from same file
-func (unparsed RawC) Process(bufferLimitBytes int, parsed chan<- m.Record) {
+func (unparsed RawC) Process(ctx context.Context, bufferLimitBytes int, parsed chan<- m.Record) {
 	lines := make(chan singleLine)
 	go unparsed.parse(lines)
 
@@ -32,34 +33,42 @@ func (unparsed RawC) Process(bufferLimitBytes int, parsed chan<- m.Record) {
 
 	stdOut, stdErr := make(chan singleLine), make(chan singleLine)
 	go func() {
-		singleLines(stdOut).process(bufferLimitBytes, parsed)
+		singleLines(stdOut).process(ctx, bufferLimitBytes, parsed)
 		wg.Done()
 	}()
 	go func() {
-		singleLines(stdErr).process(bufferLimitBytes, parsed)
+		singleLines(stdErr).process(ctx, bufferLimitBytes, parsed)
 		wg.Done()
 	}()
 
+	defer func() {
+		close(stdOut)
+		close(stdErr)
+		wg.Wait()
+		close(parsed)
+	}()
+
 	// split stdout and stderr
 	for {
-		line, ok := <-lines
+		select {
-		if !ok {
+		case <-ctx.Done():
-			close(stdOut)
-			close(stdErr)
-			wg.Wait()
-			close(parsed)
 			return
-		}
 
-		if line.StdErr {
+		case line, ok := <-lines:
-			stdErr <- line
+			if !ok {
-		} else {
+				return
-			stdOut <- line
+			}
+
+			if line.StdErr {
+				stdErr <- line
+			} else {
+				stdOut <- line
+			}
 		}
 	}
 }
 
-func (lines singleLines) process(bufferLimitBytes int, parsed chan<- m.Record) {
+func (lines singleLines) process(ctx context.Context, bufferLimitBytes int, parsed chan<- m.Record) {
 	var firstMetadata *m.ParsedMetadata
 	var buffer []byte
 
@@ -86,12 +95,17 @@ func (lines singleLines) process(bufferLimitBytes int, parsed chan<- m.Record) {
 		}
 
 		if !line.partial {
-			parsed <- m.Record{
+			select {
+			case <-ctx.Done():
+				return
+
+			case parsed <- m.Record{
 				File:   line.File.File,
 				Offset: line.Offset,
 
 				String:         string(buffer),
 				ParsedMetadata: *firstMetadata,
+			}:
 			}
 
 			buffer = nil

pkg/sender/sender.go

@@ -9,6 +9,7 @@ import (
 	m "git.k-space.ee/k-space/logmower-shipper/pkg/mongo"
 	"github.com/jtagcat/util"
 	"go.mongodb.org/mongo-driver/mongo"
+	"go.mongodb.org/mongo-driver/mongo/options"
 )
 
 const (
@@ -18,7 +19,7 @@ const (
 
 type Queue <-chan m.Record
 
-func (queue Queue) Sender(db *mongo.Collection, metricsFilename string) {
+func (queue Queue) Sender(db *mongo.Collection, metricsFilename string, cancelOnError func()) {
 	batched := make(chan []m.Record)
 
 	// metrics for batcher and queue
@@ -60,14 +61,31 @@ func (queue Queue) Sender(db *mongo.Collection, metricsFilename string) {
 			batchBson = append(batchBson, b.ToBson())
 		}
 
-		result, err := db.InsertMany(globals.MongoTimeout(context.Background()), batchBson, nil)
+		tru := true
+		result, err := db.InsertMany(globals.MongoTimeout(context.Background()), batchBson, &options.InsertManyOptions{Ordered: &tru})
+
+		var succeedCount int
+		if result != nil {
+			succeedCount = len(result.InsertedIDs)
+		}
+		promShipperDbSent.WithLabelValues(metricsFilename).Add(float64(succeedCount))
+
 		if err != nil {
 			promShipperDbSendError.WithLabelValues(metricsFilename).Add(1)
-			log.Printf("failure in batch submit to database: %e", err) // TODO: add some selective retry here or something, better error handling
-			continue
-		}
 
-		promShipperDbSent.WithLabelValues(metricsFilename).Add(float64(
+			if succeedCount == len(batch) {
-			len(result.InsertedIDs)))
+				log.Printf("all insertions in batch were successful, yet failure in database: %e", err)
+
+				cancelOnError()
+				return
+			}
+
+			firstFailed := &batch[succeedCount] // (len-1)+1
+			log.Printf("failure in inserting %q record with offset %d to database: %e",
+				firstFailed.Path, firstFailed.Offset, err)
+
+			cancelOnError()
+			return
+		}
 	}
 }