datamanager: implement import/export

* export: exports the newest data checkpoint. It forces a checkpoint before
exporting (currently no wals are exported)

* import: cleans up etcd, creates a new datasnaphot from the provided import stream
and then initializes etcd. Currently no old data is removed from the object
storage but it's just ignored.

internal/datamanager/data.go

@@ -558,3 +558,165 @@ func (d *DataManager) GetLastDataStatus() (*DataStatus, error) {
 
 	return dataStatus, dec.Decode(&dataStatus)
 }
+
+func (d *DataManager) Export(ctx context.Context, w io.Writer) error {
+	if err := d.checkpoint(ctx, true); err != nil {
+		return err
+	}
+
+	curDataStatus, err := d.GetLastDataStatus()
+	if err != nil {
+		return err
+	}
+
+	for _, dataType := range d.dataTypes {
+		var curDataStatusFiles []*DataStatusFile
+		if curDataStatus != nil {
+			curDataStatusFiles = curDataStatus.Files[dataType]
+		}
+		for _, dsf := range curDataStatusFiles {
+			dataf, err := d.ost.ReadObject(d.DataFilePath(dataType, dsf.ID))
+			if err != nil {
+				return err
+			}
+			if _, err := io.Copy(w, dataf); err != nil {
+				dataf.Close()
+				return err
+			}
+
+			dataf.Close()
+		}
+	}
+
+	return nil
+}
+
+func (d *DataManager) Import(ctx context.Context, r io.Reader) error {
+	// delete contents in etcd
+	if err := d.deleteEtcd(ctx); err != nil {
+		return err
+	}
+
+	// we require all entries of the same datatypes grouped together
+	seenDataTypes := map[string]struct{}{}
+
+	// create a new sequence, we assume that it'll be greater than previous data sequences
+	dataSequence, err := sequence.IncSequence(ctx, d.e, etcdCheckpointSeqKey)
+	if err != nil {
+		return err
+	}
+
+	dataStatus := &DataStatus{
+		DataSequence: dataSequence.String(),
+		// no last wal sequence on import
+		WalSequence: "",
+		Files:       make(map[string][]*DataStatusFile),
+	}
+
+	dataStatusFiles := []*DataStatusFile{}
+
+	var lastEntryID string
+	var curDataType string
+	var buf bytes.Buffer
+	var pos int64
+	dataFileIndex := &DataFileIndex{
+		Index: make(map[string]int64),
+	}
+	dec := json.NewDecoder(r)
+
+	for {
+		var de *DataEntry
+
+		err := dec.Decode(&de)
+		if err == io.EOF {
+			dataFileID := uuid.NewV4().String()
+			if err := d.writeDataFile(ctx, &buf, int64(buf.Len()), dataFileIndex, dataFileID, curDataType); err != nil {
+				return err
+			}
+
+			dataStatusFiles = append(dataStatusFiles, &DataStatusFile{
+				ID:          dataFileID,
+				LastEntryID: lastEntryID,
+			})
+			dataStatus.Files[curDataType] = dataStatusFiles
+
+			break
+		}
+
+		if curDataType == "" {
+			curDataType = de.DataType
+			seenDataTypes[de.DataType] = struct{}{}
+		}
+
+		mustWrite := false
+		mustReset := false
+		if pos > d.maxDataFileSize {
+			mustWrite = true
+		}
+
+		if curDataType != de.DataType {
+			if _, ok := seenDataTypes[de.DataType]; ok {
+				return errors.Errorf("dataType %q already imported", de.DataType)
+			}
+			mustWrite = true
+			mustReset = true
+		}
+
+		if mustWrite {
+			dataFileID := uuid.NewV4().String()
+			if err := d.writeDataFile(ctx, &buf, int64(buf.Len()), dataFileIndex, dataFileID, curDataType); err != nil {
+				return err
+			}
+
+			dataStatusFiles = append(dataStatusFiles, &DataStatusFile{
+				ID:          dataFileID,
+				LastEntryID: lastEntryID,
+			})
+
+			if mustReset {
+				dataStatus.Files[curDataType] = dataStatusFiles
+
+				dataStatusFiles = []*DataStatusFile{}
+				curDataType = de.DataType
+				lastEntryID = ""
+			}
+
+			dataFileIndex = &DataFileIndex{
+				Index: make(map[string]int64),
+			}
+			buf = bytes.Buffer{}
+			pos = 0
+		}
+
+		if de.ID <= lastEntryID {
+			// entries for the same datatype must be unique and ordered
+			return errors.Errorf("entry id %q is less or equal than previous entry id %q", de.ID, lastEntryID)
+		}
+		lastEntryID = de.ID
+
+		dataEntryj, err := json.Marshal(de)
+		if err != nil {
+			return err
+		}
+		if _, err := buf.Write(dataEntryj); err != nil {
+			return err
+		}
+		dataFileIndex.Index[de.ID] = pos
+		pos += int64(len(dataEntryj))
+	}
+
+	dataStatusj, err := json.Marshal(dataStatus)
+	if err != nil {
+		return err
+	}
+	if err := d.ost.WriteObject(d.dataStatusPath(dataSequence.String()), bytes.NewReader(dataStatusj), int64(len(dataStatusj)), true); err != nil {
+		return err
+	}
+
+	// initialize etcd providing the specific datastatus
+	if err := d.InitEtcd(ctx, dataStatus); err != nil {
+		return err
+	}
+
+	return nil
+}

internal/datamanager/datamanager_test.go

@@ -15,6 +15,7 @@
 package datamanager
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
@@ -31,6 +32,7 @@ import (
 	"agola.io/agola/internal/objectstorage/posix"
 	ostypes "agola.io/agola/internal/objectstorage/types"
 	"agola.io/agola/internal/testutil"
+	"agola.io/agola/internal/util"
 
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
@@ -738,15 +740,19 @@ func testCheckpoint(t *testing.T, basePath string) {
 func checkDataFiles(ctx context.Context, t *testing.T, dm *DataManager, expectedEntriesMap map[string]*DataEntry) error {
 	// read the data file
 	curDataStatus, err := dm.GetLastDataStatus()
+	t.Logf("curDataStatus: %s", util.Dump(curDataStatus))
 	if err != nil {
 		return err
 	}
 
 	allEntriesMap := map[string]*DataEntry{}
-	var prevLastEntryID string
 
-	for i, file := range curDataStatus.Files["datatype01"] {
+	for dataType := range curDataStatus.Files {
-		dataFileIndexf, err := dm.ost.ReadObject(dm.DataFileIndexPath("datatype01", file.ID))
+		var prevLastEntryID string
+		t.Logf("dataType: %q", dataType)
+		for i, file := range curDataStatus.Files[dataType] {
+			t.Logf("data file: %d %q", i, file)
+			dataFileIndexf, err := dm.ost.ReadObject(dm.DataFileIndexPath(dataType, file.ID))
 			if err != nil {
 				return err
 			}
@@ -761,7 +767,7 @@ func checkDataFiles(ctx context.Context, t *testing.T, dm *DataManager, expected
 			dataFileIndexf.Close()
 			dataEntriesMap := map[string]*DataEntry{}
 			dataEntries := []*DataEntry{}
-		dataf, err := dm.ost.ReadObject(dm.DataFilePath("datatype01", file.ID))
+			dataf, err := dm.ost.ReadObject(dm.DataFilePath(dataType, file.ID))
 			if err != nil {
 				return err
 			}
@@ -825,6 +831,7 @@ func checkDataFiles(ctx context.Context, t *testing.T, dm *DataManager, expected
 			}
 			prevLastEntryID = file.LastEntryID
 		}
+	}
 
 	// check that the number of entries is right
 	if len(allEntriesMap) != len(expectedEntriesMap) {
@@ -836,3 +843,259 @@ func checkDataFiles(ctx context.Context, t *testing.T, dm *DataManager, expected
 
 	return nil
 }
+
+func TestExportImport(t *testing.T) {
+	dir, err := ioutil.TempDir("", "agola")
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	etcdDir, err := ioutil.TempDir(dir, "etcd")
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	tetcd := setupEtcd(t, etcdDir)
+	defer shutdownEtcd(tetcd)
+
+	ctx, cancel := context.WithCancel(context.Background())
+
+	ostDir, err := ioutil.TempDir(dir, "ost")
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	ost, err := posix.New(ostDir)
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	dmConfig := &DataManagerConfig{
+		BasePath: "basepath",
+		E:        tetcd.TestEtcd.Store,
+		OST:      objectstorage.NewObjStorage(ost, "/"),
+		// remove almost all wals to see that they are removed also from changes
+		EtcdWalsKeepNum: 1,
+		DataTypes:       []string{"datatype01", "datatype02"},
+		// checkpoint also with only one wal
+		MinCheckpointWalsNum: 1,
+		// use a small maxDataFileSize
+		MaxDataFileSize: 10 * 1024,
+	}
+	dm, err := NewDataManager(ctx, logger, dmConfig)
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	dmReadyCh := make(chan struct{})
+	go func() { _ = dm.Run(ctx, dmReadyCh) }()
+	<-dmReadyCh
+
+	time.Sleep(5 * time.Second)
+
+	contents := "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+
+	expectedEntries := map[string]*DataEntry{}
+
+	// test insert from scratch (no current entries)
+	actionGroups := [][]*Action{}
+	actions := []*Action{}
+	for i := 200; i < 400; i++ {
+		action := &Action{
+			ActionType: ActionTypePut,
+			ID:         fmt.Sprintf("object%04d", i),
+			DataType:   "datatype01",
+			Data:       []byte(fmt.Sprintf(`{ "ID": "%d", "Contents": %s }`, i, contents)),
+		}
+		actions = append(actions, action)
+	}
+	actionGroups = append(actionGroups, actions)
+
+	actions = []*Action{}
+	for i := 600; i < 1000; i++ {
+		action := &Action{
+			ActionType: ActionTypePut,
+			ID:         fmt.Sprintf("object%04d", i),
+			DataType:   "datatype02",
+			Data:       []byte(fmt.Sprintf(`{ "ID": "%d", "Contents": %s }`, i, contents)),
+		}
+		actions = append(actions, action)
+	}
+	actionGroups = append(actionGroups, actions)
+
+	for _, actionGroup := range actionGroups {
+		for _, action := range actionGroup {
+			switch action.ActionType {
+			case ActionTypePut:
+				expectedEntries[action.ID] = &DataEntry{ID: action.ID, DataType: action.DataType, Data: action.Data}
+			case ActionTypeDelete:
+				delete(expectedEntries, action.ID)
+			}
+		}
+	}
+
+	for _, actionGroup := range actionGroups {
+		// populate with a wal
+		_, err := dm.WriteWal(ctx, actionGroup, nil)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+	}
+
+	// wait for the event to be read
+	time.Sleep(500 * time.Millisecond)
+
+	var export bytes.Buffer
+	if err := dm.Export(ctx, &export); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	t.Logf("stopping datamanager")
+	cancel()
+
+	time.Sleep(5 * time.Second)
+
+	t.Logf("stopping etcd")
+	// Reset etcd
+	shutdownEtcd(tetcd)
+	if err := tetcd.WaitDown(10 * time.Second); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	t.Logf("resetting etcd")
+	os.RemoveAll(etcdDir)
+	t.Logf("starting etcd")
+	tetcd = setupEtcd(t, etcdDir)
+	if err := tetcd.Start(); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	defer shutdownEtcd(tetcd)
+
+	ostDir, err = ioutil.TempDir(dir, "ost")
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	ost, err = posix.New(ostDir)
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	ctx, cancel = context.WithCancel(context.Background())
+
+	dmConfig = &DataManagerConfig{
+		BasePath: "basepath",
+		E:        tetcd.TestEtcd.Store,
+		OST:      objectstorage.NewObjStorage(ost, "/"),
+		// remove almost all wals to see that they are removed also from changes
+		EtcdWalsKeepNum: 1,
+		DataTypes:       []string{"datatype01", "datatype02"},
+		// checkpoint also with only one wal
+		MinCheckpointWalsNum: 1,
+		// use a small maxDataFileSize
+		MaxDataFileSize: 10 * 1024,
+		MaintenanceMode: true,
+	}
+	dm, err = NewDataManager(ctx, logger, dmConfig)
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	dmReadyCh = make(chan struct{})
+	go func() { _ = dm.Run(ctx, dmReadyCh) }()
+	<-dmReadyCh
+
+	time.Sleep(5 * time.Second)
+	if err := dm.Import(ctx, &export); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	if err := checkDataFiles(ctx, t, dm, expectedEntries); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	t.Logf("stopping datamanager")
+	cancel()
+
+	time.Sleep(5 * time.Second)
+
+	ctx = context.Background()
+
+	// restart datamanager in normal mode
+	dmConfig = &DataManagerConfig{
+		BasePath: "basepath",
+		E:        tetcd.TestEtcd.Store,
+		OST:      objectstorage.NewObjStorage(ost, "/"),
+		// remove almost all wals to see that they are removed also from changes
+		EtcdWalsKeepNum: 1,
+		DataTypes:       []string{"datatype01", "datatype02"},
+		// checkpoint also with only one wal
+		MinCheckpointWalsNum: 1,
+		// use a small maxDataFileSize
+		MaxDataFileSize: 10 * 1024,
+	}
+	dm, err = NewDataManager(ctx, logger, dmConfig)
+	if err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+	dmReadyCh = make(chan struct{})
+	go func() { _ = dm.Run(ctx, dmReadyCh) }()
+	<-dmReadyCh
+
+	time.Sleep(5 * time.Second)
+
+	if err := checkDataFiles(ctx, t, dm, expectedEntries); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	actionGroups = [][]*Action{}
+	actions = []*Action{}
+	for i := 400; i < 600; i++ {
+		action := &Action{
+			ActionType: ActionTypePut,
+			ID:         fmt.Sprintf("object%04d", i),
+			DataType:   "datatype01",
+			Data:       []byte(fmt.Sprintf(`{ "ID": "%d", "Contents": %s }`, i, contents)),
+		}
+		actions = append(actions, action)
+	}
+	actionGroups = append(actionGroups, actions)
+
+	actions = []*Action{}
+	for i := 1000; i < 1400; i++ {
+		action := &Action{
+			ActionType: ActionTypePut,
+			ID:         fmt.Sprintf("object%04d", i),
+			DataType:   "datatype02",
+			Data:       []byte(fmt.Sprintf(`{ "ID": "%d", "Contents": %s }`, i, contents)),
+		}
+		actions = append(actions, action)
+	}
+	actionGroups = append(actionGroups, actions)
+
+	for _, actionGroup := range actionGroups {
+		for _, action := range actionGroup {
+			switch action.ActionType {
+			case ActionTypePut:
+				expectedEntries[action.ID] = &DataEntry{ID: action.ID, DataType: action.DataType, Data: action.Data}
+			case ActionTypeDelete:
+				delete(expectedEntries, action.ID)
+			}
+		}
+	}
+
+	for _, actionGroup := range actionGroups {
+		// populate with a wal
+		_, err := dm.WriteWal(ctx, actionGroup, nil)
+		if err != nil {
+			t.Fatalf("unexpected err: %v", err)
+		}
+	}
+
+	// wait for the event to be read
+	time.Sleep(500 * time.Millisecond)
+
+	if err := dm.checkpoint(ctx, false); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+
+	if err := checkDataFiles(ctx, t, dm, expectedEntries); err != nil {
+		t.Fatalf("unexpected err: %v", err)
+	}
+}