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refactor: use modern Protobuf encoder (#9817)

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At a high level, this is what I've done and why:

- I'm moving the protobuf generation for the `protocol`, `discovery` and
`db` packages to the modern alternatives, and using `buf` to generate
because it's nice and simple.
- After trying various approaches on how to integrate the new types with
the existing code, I opted for splitting off our own data model types
from the on-the-wire generated types. This means we can have a
`FileInfo` type with nicer ergonomics and lots of methods, while the
protobuf generated type stays clean and close to the wire protocol. It
does mean copying between the two when required, which certainly adds a
small amount of inefficiency. If we want to walk this back in the future
and use the raw generated type throughout, that's possible, this however
makes the refactor smaller (!) as it doesn't change everything about the
type for everyone at the same time.
- I have simply removed in cold blood a significant number of old
database migrations. These depended on previous generations of generated
messages of various kinds and were annoying to support in the new
fashion. The oldest supported database version now is the one from
Syncthing 1.9.0 from Sep 7, 2020.
- I changed config structs to be regular manually defined structs.

For the sake of discussion, some things I tried that turned out not to
work...

### Embedding / wrapping

Embedding the protobuf generated structs in our existing types as a data
container and keeping our methods and stuff:

```
package protocol

type FileInfo struct {
  *generated.FileInfo
}
```

This generates a lot of problems because the internal shape of the
generated struct is quite different (different names, different types,
more pointers), because initializing it doesn't work like you'd expect
(i.e., you end up with an embedded nil pointer and a panic), and because
the types of child types don't get wrapped. That is, even if we also
have a similar wrapper around a `Vector`, that's not the type you get
when accessing `someFileInfo.Version`, you get the `*generated.Vector`
that doesn't have methods, etc.

### Aliasing

```
package protocol

type FileInfo = generated.FileInfo
```

Doesn't help because you can't attach methods to it, plus all the above.

### Generating the types into the target package like we do now and
attaching methods

This fails because of the different shape of the generated type (as in
the embedding case above) plus the generated struct already has a bunch
of methods that we can't necessarily override properly (like `String()`
and a bunch of getters).

### Methods to functions

I considered just moving all the methods we attach to functions in a
specific package, so that for example

```
package protocol

func (f FileInfo) Equal(other FileInfo) bool
```

would become

```
package fileinfos

func Equal(a, b *generated.FileInfo) bool
```

and this would mostly work, but becomes quite verbose and cumbersome,
and somewhat limits discoverability (you can't see what methods are
available on the type in auto completions, etc). In the end I did this
in some cases, like in the database layer where a lot of things like
`func (fv *FileVersion) IsEmpty() bool` becomes `func fvIsEmpty(fv
*generated.FileVersion)` because they were anyway just internal methods.

Fixes #8247
This commit is contained in:
Jakob Borg
2024-12-01 16:50:17 +01:00
committed by GitHub
parent 2b8ee4c7a5
commit 77970d5113
203 changed files with 7437 additions and 28636 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/model/folder.go
+35 -35
View File
@@ -372,7 +372,7 @@ func (f *folder) pull() (success bool, err error) {
if err != nil {
return false, err
}
snap.WithNeed(protocol.LocalDeviceID, func(intf protocol.FileIntf) bool {
snap.WithNeed(protocol.LocalDeviceID, func(intf protocol.FileInfo) bool {
abort = false
return false
})
@@ -702,7 +702,7 @@ func (f *folder) scanSubdirsChangedAndNew(subDirs []string, batch *scanBatch) (i
}
func (f *folder) scanSubdirsDeletedAndIgnored(subDirs []string, batch *scanBatch) (int, error) {
var toIgnore []db.FileInfoTruncated
var toIgnore []protocol.FileInfo
ignoredParent := ""
changes := 0
snap, err := f.dbSnapshot()
@@ -714,24 +714,23 @@ func (f *folder) scanSubdirsDeletedAndIgnored(subDirs []string, batch *scanBatch
for _, sub := range subDirs {
var iterError error
snap.WithPrefixedHaveTruncated(protocol.LocalDeviceID, sub, func(fi protocol.FileIntf) bool {
snap.WithPrefixedHaveTruncated(protocol.LocalDeviceID, sub, func(fi protocol.FileInfo) bool {
select {
case <-f.ctx.Done():
return false
default:
}
file := fi.(db.FileInfoTruncated)
if err := batch.FlushIfFull(); err != nil {
iterError = err
return false
}
if ignoredParent != "" && !fs.IsParent(file.Name, ignoredParent) {
if ignoredParent != "" && !fs.IsParent(fi.Name, ignoredParent) {
for _, file := range toIgnore {
l.Debugln("marking file as ignored", file)
nf := file.ConvertToIgnoredFileInfo()
nf := file
nf.SetIgnored()
if batch.Update(nf, snap) {
changes++
}
@@ -744,38 +743,39 @@ func (f *folder) scanSubdirsDeletedAndIgnored(subDirs []string, batch *scanBatch
ignoredParent = ""
}
switch ignored := f.ignores.Match(file.Name).IsIgnored(); {
case file.IsIgnored() && ignored:
switch ignored := f.ignores.Match(fi.Name).IsIgnored(); {
case fi.IsIgnored() && ignored:
return true
case !file.IsIgnored() && ignored:
case !fi.IsIgnored() && ignored:
// File was not ignored at last pass but has been ignored.
if file.IsDirectory() {
if fi.IsDirectory() {
// Delay ignoring as a child might be unignored.
toIgnore = append(toIgnore, file)
toIgnore = append(toIgnore, fi)
if ignoredParent == "" {
// If the parent wasn't ignored already, set
// this path as the "highest" ignored parent
ignoredParent = file.Name
ignoredParent = fi.Name
}
return true
}
l.Debugln("marking file as ignored", file)
nf := file.ConvertToIgnoredFileInfo()
l.Debugln("marking file as ignored", fi)
nf := fi
nf.SetIgnored()
if batch.Update(nf, snap) {
changes++
}
case file.IsIgnored() && !ignored:
case fi.IsIgnored() && !ignored:
// Successfully scanned items are already un-ignored during
// the scan, so check whether it is deleted.
fallthrough
case !file.IsIgnored() && !file.IsDeleted() && !file.IsUnsupported():
case !fi.IsIgnored() && !fi.IsDeleted() && !fi.IsUnsupported():
// The file is not ignored, deleted or unsupported. Lets check if
// it's still here. Simply stat:ing it won't do as there are
// tons of corner cases (e.g. parent dir->symlink, missing
// permissions)
if !osutil.IsDeleted(f.mtimefs, file.Name) {
if !osutil.IsDeleted(f.mtimefs, fi.Name) {
if ignoredParent != "" {
// Don't ignore parents of this not ignored item
toIgnore = toIgnore[:0]
@@ -783,9 +783,10 @@ func (f *folder) scanSubdirsDeletedAndIgnored(subDirs []string, batch *scanBatch
}
return true
}
nf := file.ConvertToDeletedFileInfo(f.shortID)
nf := fi
nf.SetDeleted(f.shortID)
nf.LocalFlags = f.localFlags
if file.ShouldConflict() {
if fi.ShouldConflict() {
// We do not want to override the global version with
// the deleted file. Setting to an empty version makes
// sure the file gets in sync on the following pull.
@@ -795,30 +796,30 @@ func (f *folder) scanSubdirsDeletedAndIgnored(subDirs []string, batch *scanBatch
if batch.Update(nf, snap) {
changes++
}
case file.IsDeleted() && file.IsReceiveOnlyChanged():
case fi.IsDeleted() && fi.IsReceiveOnlyChanged():
switch f.Type {
case config.FolderTypeReceiveOnly, config.FolderTypeReceiveEncrypted:
switch gf, ok := snap.GetGlobal(file.Name); {
switch gf, ok := snap.GetGlobal(fi.Name); {
case !ok:
case gf.IsReceiveOnlyChanged():
l.Debugln("removing deleted, receive-only item that is globally receive-only from db", file)
batch.Remove(file.Name)
l.Debugln("removing deleted, receive-only item that is globally receive-only from db", fi)
batch.Remove(fi.Name)
changes++
case gf.IsDeleted():
// Our item is deleted and the global item is deleted too. We just
// pretend it is a normal deleted file (nobody cares about that).
l.Debugf("%v scanning: Marking globally deleted item as not locally changed: %v", f, file.Name)
file.LocalFlags &^= protocol.FlagLocalReceiveOnly
if batch.Update(file.ConvertDeletedToFileInfo(), snap) {
l.Debugf("%v scanning: Marking globally deleted item as not locally changed: %v", f, fi.Name)
fi.LocalFlags &^= protocol.FlagLocalReceiveOnly
if batch.Update(fi, snap) {
changes++
}
}
default:
// No need to bump the version for a file that was and is
// deleted and just the folder type/local flags changed.
file.LocalFlags &^= protocol.FlagLocalReceiveOnly
l.Debugln("removing receive-only flag on deleted item", file)
if batch.Update(file.ConvertDeletedToFileInfo(), snap) {
fi.LocalFlags &^= protocol.FlagLocalReceiveOnly
l.Debugln("removing receive-only flag on deleted item", fi)
if batch.Update(fi, snap) {
changes++
}
}
@@ -835,8 +836,9 @@ func (f *folder) scanSubdirsDeletedAndIgnored(subDirs []string, batch *scanBatch
if iterError == nil && len(toIgnore) > 0 {
for _, file := range toIgnore {
l.Debugln("marking file as ignored", f)
nf := file.ConvertToIgnoredFileInfo()
l.Debugln("marking file as ignored", file)
nf := file
nf.SetIgnored()
if batch.Update(nf, snap) {
changes++
}
@@ -863,9 +865,7 @@ func (f *folder) findRename(snap *db.Snapshot, file protocol.FileInfo, alreadyUs
found := false
nf := protocol.FileInfo{}
snap.WithBlocksHash(file.BlocksHash, func(ifi protocol.FileIntf) bool {
fi := ifi.(protocol.FileInfo)
snap.WithBlocksHash(file.BlocksHash, func(fi protocol.FileInfo) bool {
select {
case <-f.ctx.Done():
return false