rclone/cmd/bisync/queue.go
nielash 6d6dc00abb bisync: rollback listing on error
Before this change, bisync had no mechanism for "retrying" a file again next
time, in the event of an unexpected and possibly temporary error. After this
change, bisync is now essentially able to mark a file as needing to be
rechecked next time. Bisync does this by keeping one prior listing on hand at
all times. In a low-confidence situation, bisync can revert a given file row
back to its state at the end of the last known successful sync, ensuring that
any subsequent changes will be re-noticed on the next run.
This can potentially be helpful for a dynamically changing file system, where
files may be changing quickly while bisync is working with them.
2024-01-20 14:50:08 -05:00

255 lines
6.6 KiB
Go

package bisync
import (
"context"
"encoding/json"
"fmt"
"io"
"sort"
mutex "sync" // renamed as "sync" already in use
"time"
"github.com/rclone/rclone/cmd/bisync/bilib"
"github.com/rclone/rclone/fs"
"github.com/rclone/rclone/fs/filter"
"github.com/rclone/rclone/fs/operations"
"github.com/rclone/rclone/fs/sync"
"golang.org/x/text/unicode/norm"
)
// Results represents a pair of synced files, as reported by the LoggerFn
// Bisync uses this to determine what happened during the sync, and modify the listings accordingly
type Results struct {
Src string
Dst string
Name string
Size int64
Modtime time.Time
Hash string
Flags string
Sigil operations.Sigil
Err error
Winner operations.Winner
IsWinner bool
IsSrc bool
IsDst bool
}
var logger = operations.NewLoggerOpt()
var lock mutex.Mutex
var ignoreListingChecksum bool
// FsPathIfAny handles type assertions and returns a formatted bilib.FsPath if valid, otherwise ""
func FsPathIfAny(x fs.DirEntry) string {
obj, ok := x.(fs.Object)
if x != nil && ok {
return bilib.FsPath(obj.Fs())
}
return ""
}
func resultName(result Results, side, src, dst fs.DirEntry) string {
if side != nil {
return side.Remote()
} else if result.IsSrc && dst != nil {
return dst.Remote()
} else if src != nil {
return src.Remote()
}
return ""
}
// WriteResults is Bisync's LoggerFn
func WriteResults(ctx context.Context, sigil operations.Sigil, src, dst fs.DirEntry, err error) {
lock.Lock()
defer lock.Unlock()
opt := operations.GetLoggerOpt(ctx)
result := Results{
Sigil: sigil,
Src: FsPathIfAny(src),
Dst: FsPathIfAny(dst),
Err: err,
}
result.Winner = operations.WinningSide(ctx, sigil, src, dst, err)
fss := []fs.DirEntry{src, dst}
for i, side := range fss {
result.Name = resultName(result, side, src, dst)
result.IsSrc = i == 0
result.IsDst = i == 1
result.Flags = "-"
if side != nil {
result.Size = side.Size()
result.Modtime = side.ModTime(ctx).In(time.UTC)
if !ignoreListingChecksum {
sideObj, ok := side.(fs.ObjectInfo)
if ok {
result.Hash, _ = sideObj.Hash(ctx, sideObj.Fs().Hashes().GetOne())
}
}
}
result.IsWinner = result.Winner.Obj == side
// used during resync only
if err == fs.ErrorIsDir {
if src != nil {
result.Src = src.Remote()
result.Name = src.Remote()
} else {
result.Dst = dst.Remote()
result.Name = dst.Remote()
}
result.Flags = "d"
result.Size = 0
}
fs.Debugf(nil, "writing result: %v", result)
err := json.NewEncoder(opt.JSON).Encode(result)
if err != nil {
fs.Errorf(result, "Error encoding JSON: %v", err)
}
}
}
// ReadResults decodes the JSON data from WriteResults
func ReadResults(results io.Reader) []Results {
dec := json.NewDecoder(results)
var slice []Results
for {
var r Results
if err := dec.Decode(&r); err == io.EOF {
break
}
fs.Debugf(nil, "result: %v", r)
slice = append(slice, r)
}
return slice
}
func (b *bisyncRun) fastCopy(ctx context.Context, fsrc, fdst fs.Fs, files bilib.Names, queueName string) ([]Results, error) {
if err := b.saveQueue(files, queueName); err != nil {
return nil, err
}
ctxCopy, filterCopy := filter.AddConfig(b.opt.setDryRun(ctx))
for _, file := range files.ToList() {
if err := filterCopy.AddFile(file); err != nil {
return nil, err
}
// macOS
if err := filterCopy.AddFile(norm.NFD.String(file)); err != nil {
return nil, err
}
}
ignoreListingChecksum = b.opt.IgnoreListingChecksum
logger.LoggerFn = WriteResults
ctxCopyLogger := operations.WithSyncLogger(ctxCopy, logger)
var err error
if b.opt.Resync {
err = sync.CopyDir(ctxCopyLogger, fdst, fsrc, b.opt.CreateEmptySrcDirs)
} else {
b.testFn()
err = sync.Sync(ctxCopyLogger, fdst, fsrc, b.opt.CreateEmptySrcDirs)
}
fs.Debugf(nil, "logger is: %v", logger)
getResults := ReadResults(logger.JSON)
fs.Debugf(nil, "Got %v results for %v", len(getResults), queueName)
lineFormat := "%s %8d %s %s %s %q\n"
for _, result := range getResults {
fs.Debugf(nil, lineFormat, result.Flags, result.Size, result.Hash, "", result.Modtime, result.Name)
}
return getResults, err
}
func (b *bisyncRun) resyncDir(ctx context.Context, fsrc, fdst fs.Fs) ([]Results, error) {
ignoreListingChecksum = b.opt.IgnoreListingChecksum
logger.LoggerFn = WriteResults
ctxCopyLogger := operations.WithSyncLogger(ctx, logger)
err := sync.CopyDir(ctxCopyLogger, fdst, fsrc, b.opt.CreateEmptySrcDirs)
fs.Debugf(nil, "logger is: %v", logger)
getResults := ReadResults(logger.JSON)
fs.Debugf(nil, "Got %v results for %v", len(getResults), "resync")
return getResults, err
}
// operation should be "make" or "remove"
func (b *bisyncRun) syncEmptyDirs(ctx context.Context, dst fs.Fs, candidates bilib.Names, dirsList *fileList, results *[]Results, operation string) {
if b.opt.CreateEmptySrcDirs && (!b.opt.Resync || operation == "make") {
candidatesList := candidates.ToList()
if operation == "remove" {
// reverse the sort order to ensure we remove subdirs before parent dirs
sort.Sort(sort.Reverse(sort.StringSlice(candidatesList)))
}
for _, s := range candidatesList {
var direrr error
if dirsList.has(s) { //make sure it's a dir, not a file
r := Results{}
r.Name = s
r.Size = 0
r.Modtime = dirsList.getTime(s).In(time.UTC)
r.Flags = "d"
r.Err = nil
r.Winner = operations.Winner{ // note: Obj not set
Side: "src",
Err: nil,
}
rSrc := r
rDst := r
rSrc.IsSrc = true
rSrc.IsDst = false
rDst.IsSrc = false
rDst.IsDst = true
rSrc.IsWinner = true
rDst.IsWinner = false
if operation == "remove" {
// directories made empty by the sync will have already been deleted during the sync
// this just catches the already-empty ones (excluded from sync by --files-from filter)
direrr = operations.TryRmdir(ctx, dst, s)
rSrc.Sigil = operations.MissingOnSrc
rDst.Sigil = operations.MissingOnSrc
rSrc.Dst = s
rDst.Dst = s
rSrc.Winner.Side = "none"
rDst.Winner.Side = "none"
} else if operation == "make" {
direrr = operations.Mkdir(ctx, dst, s)
rSrc.Sigil = operations.MissingOnDst
rDst.Sigil = operations.MissingOnDst
rSrc.Src = s
rDst.Src = s
} else {
direrr = fmt.Errorf("invalid operation. Expected 'make' or 'remove', received '%q'", operation)
}
if direrr != nil {
fs.Debugf(nil, "Error syncing directory: %v", direrr)
} else {
*results = append(*results, rSrc, rDst)
}
}
}
}
}
func (b *bisyncRun) saveQueue(files bilib.Names, jobName string) error {
if !b.opt.SaveQueues {
return nil
}
queueFile := fmt.Sprintf("%s.%s.que", b.basePath, jobName)
return files.Save(queueFile)
}