implement context cancellation on db error

This commit is contained in:
rasmus 2022-11-09 19:56:44 +02:00
parent 801ac76eef
commit f26438f32a
3 changed files with 94 additions and 56 deletions

View File

@ -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
})
}
func (f File) launchChannels(cancel func(), db *mongo.Collection, recordLimitBytes int) (_ chan<- lines.Raw, deferFn func()) {
lineOut := make(chan lines.Raw)
sctx, scancel := context.WithCancel(context.Background())
cancelAll := func() {
cancel()
scancel()
}
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) trySubmit(ctx context.Context, db *mongo.Collection, sendQueue chan<- lines.Raw) error {
func (f File) process(ctx context.Context, db *mongo.Collection, recordLimitBytes int) error {
lFile := lines.File(f) // file.File, but avoiding import cycle
// TODO: better way for respecting ?killing sender for retry
for {
if len(sendQueue) == 0 {
break
}
time.Sleep(time.Second)
}
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)
defer cancel()
promFileInitialSeekSkipped.WithLabelValues(f.MetricsName).Set(float64(dbOffset))
lineChan, errChan, err := util.TailFile(sctx, f.Path, dbOffset, io.SeekStart)
lineIn, 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,
}:
}
}
}

View File

@ -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)
@ -32,22 +33,29 @@ 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()
}()
// split stdout and stderr
for {
line, ok := <-lines
if !ok {
defer func() {
close(stdOut)
close(stdErr)
wg.Wait()
close(parsed)
}()
// split stdout and stderr
for {
select {
case <-ctx.Done():
return
case line, ok := <-lines:
if !ok {
return
}
@ -58,8 +66,9 @@ func (unparsed RawC) Process(bufferLimitBytes int, parsed chan<- m.Record) {
}
}
}
}
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

View File

@ -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
if succeedCount == len(batch) {
log.Printf("all insertions in batch were successful, yet failure in database: %e", err)
cancelOnError()
return
}
promShipperDbSent.WithLabelValues(metricsFilename).Add(float64(
len(result.InsertedIDs)))
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
}
}
}