bolt.go

/*
 * Copyright (c) 2018. Abstrium SAS <team (at) pydio.com>
 * This file is part of Pydio Cells.
 *
 * Pydio Cells is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Pydio Cells is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with Pydio Cells.  If not, see <http://www.gnu.org/licenses/>.
 *
 * The latest code can be found at <https://pydio.com>.
 */

package versions

import (
	"context"
	"encoding/binary"
	"os"
	"time"

	bolt "github.com/etcd-io/bbolt"
	"github.com/micro/go-micro/errors"
	"github.com/micro/protobuf/proto"
	"go.uber.org/zap"

	"github.com/pydio/cells/common"
	"github.com/pydio/cells/common/log"
	"github.com/pydio/cells/common/proto/tree"
)

var (
	bucketName = []byte("versions")
)

type BoltStore struct {
	// Internal DB
	db *bolt.DB
	// For Testing purpose : delete file after closing
	DeleteOnClose bool
	// Path to the DB file
	DbPath string
}

func NewBoltStore(fileName string, deleteOnClose ...bool) (*BoltStore, error) {

	bs := &BoltStore{
		DbPath: fileName,
	}
	if len(deleteOnClose) > 0 && deleteOnClose[0] {
		bs.DeleteOnClose = true
	}
	options := bolt.DefaultOptions
	options.Timeout = 5 * time.Second
	db, err := bolt.Open(fileName, 0644, options)
	if err != nil {
		return nil, err
	}
	bs.db = db
	e2 := db.Update(func(tx *bolt.Tx) error {
		_, e := tx.CreateBucketIfNotExists(bucketName)
		return e
	})
	return bs, e2

}

func (b *BoltStore) Close() error {
	err := b.db.Close()
	if b.DeleteOnClose {
		os.Remove(b.DbPath)
	}
	return err
}

// GetLastVersion retrieves the last version registered for this node.
func (b *BoltStore) GetLastVersion(nodeUuid string) (log *tree.ChangeLog, err error) {

	err = b.db.View(func(tx *bolt.Tx) error {

		bucket := tx.Bucket(bucketName)
		if bucket == nil {
			return errors.NotFound(common.SERVICE_VERSIONS, "Bucket not found, this is not normal")
		}
		nodeBucket := bucket.Bucket([]byte(nodeUuid))
		if nodeBucket == nil {
			// Ignore not found
			return nil
		}
		c := nodeBucket.Cursor()
		_, v := c.Last()
		theLog := &tree.ChangeLog{}
		e := proto.Unmarshal(v, theLog)
		if e != nil {
			return e
		}
		log = theLog
		return nil
	})

	return log, err
}

// GetVersions returns all versions from the node bucket, in reverse order (last inserted first).
func (b *BoltStore) GetVersions(nodeUuid string) (chan *tree.ChangeLog, chan bool) {

	logChan := make(chan *tree.ChangeLog)
	done := make(chan bool, 1)

	go func() {

		e := b.db.View(func(tx *bolt.Tx) error {

			defer func() {
				done <- true
				close(done)
			}()
			bucket := tx.Bucket(bucketName)
			if bucket == nil {
				return errors.NotFound(common.SERVICE_VERSIONS, "Bucket not found, this is not normal")
			}
			nodeBucket := bucket.Bucket([]byte(nodeUuid))
			if nodeBucket == nil {
				return errors.NotFound(common.SERVICE_VERSIONS, "No bucket found for this node")
			}
			c := nodeBucket.Cursor()

			for k, v := c.Last(); k != nil; k, v = c.Prev() {
				aLog := &tree.ChangeLog{}
				e := proto.Unmarshal(v, aLog)
				if e != nil {
					return e
				}
				log.Logger(context.Background()).Debug("Versions:Bolt", aLog.Zap())
				logChan <- aLog
			}

			return nil
		})
		if e != nil {
			log.Logger(context.Background()).Error("listVersions", zap.Error(e))
		}

	}()

	return logChan, done
}

// StoreVersion stores a version in the node bucket.
func (b *BoltStore) StoreVersion(nodeUuid string, log *tree.ChangeLog) error {

	return b.db.Update(func(tx *bolt.Tx) error {

		bucket := tx.Bucket(bucketName)
		if bucket == nil {
			return errors.NotFound(common.SERVICE_VERSIONS, "bucket not found")
		}
		nodeBucket, err := bucket.CreateBucketIfNotExists([]byte(nodeUuid))
		if err != nil {
			return err
		}
		newValue, e := proto.Marshal(log)
		if e != nil {
			return e
		}

		objectKey, _ := nodeBucket.NextSequence()
		k := make([]byte, 8)
		binary.BigEndian.PutUint64(k, objectKey)
		return nodeBucket.Put(k, newValue)

	})
}

// GetVersion retrieves a specific version from the node bucket.
func (b *BoltStore) GetVersion(nodeUuid string, versionId string) (*tree.ChangeLog, error) {

	version := &tree.ChangeLog{}

	b.db.View(func(tx *bolt.Tx) error {

		bucket := tx.Bucket(bucketName)
		if bucket == nil {
			return errors.NotFound(common.SERVICE_VERSIONS, "bucket not found")
		}
		nodeBucket := bucket.Bucket([]byte(nodeUuid))
		if nodeBucket == nil {
			return nil
		}

		c := nodeBucket.Cursor()
		for k, v := c.First(); k != nil; k, v = c.Next() {
			vers := &tree.ChangeLog{}
			if e := proto.Unmarshal(v, vers); e == nil && vers.Uuid == versionId {
				version = vers
				break
			}
		}
		return nil
	})

	return version, nil
}

// DeleteVersionsForNode deletes whole node bucket at once.
func (b *BoltStore) DeleteVersionsForNode(nodeUuid string, versions ...*tree.ChangeLog) error {

	return b.db.Update(func(tx *bolt.Tx) error {

		bucket := tx.Bucket(bucketName)
		if bucket == nil {
			return errors.NotFound(common.SERVICE_VERSIONS, "bucket not found")
		}
		nodeBucket := bucket.Bucket([]byte(nodeUuid))
		if nodeBucket != nil {
			if len(versions) > 0 { // delete some specific versions
				c := nodeBucket.Cursor()
				var keys [][]byte
				for k, v := c.First(); k != nil; k, v = c.Next() {
					vers := &tree.ChangeLog{}
					if e := proto.Unmarshal(v, vers); e == nil {
						for _, version := range versions {
							if vers.Uuid == version.Uuid {
								keys = append(keys, k)
							}
						}
					}
				}
				for _, key := range keys {
					nodeBucket.Delete(key)
				}

			} else { // delete whole bucket
				return bucket.DeleteBucket([]byte(nodeUuid))
			}
		}
		return nil
	})
}

// ListAllVersionedNodesUuids lists all nodes uuids
func (b *BoltStore) ListAllVersionedNodesUuids() (chan string, chan bool, chan error) {
	idsChan := make(chan string)
	done := make(chan bool, 1)
	errChan := make(chan error)

	go func() {

		e := b.db.View(func(tx *bolt.Tx) error {

			defer func() {
				done <- true
				close(done)
			}()
			bucket := tx.Bucket(bucketName)
			if bucket == nil {
				return errors.NotFound(common.SERVICE_VERSIONS, "version bucket not found")
			}
			c := bucket.Cursor()
			for k, _ := c.First(); k != nil; k, _ = c.Next() {
				key := string(k)
				idsChan <- key
			}

			return nil
		})
		if e != nil {
			errChan <- e
		}

	}()

	return idsChan, done, errChan
}