seaweedfs/weed/mount/meta_cache/meta_cache_subscribe.go
Ryan Russell d65bdeef08
docs(meta_cache): readability fixes (#3691)
Signed-off-by: Ryan Russell <git@ryanrussell.org>

Signed-off-by: Ryan Russell <git@ryanrussell.org>
2022-09-15 02:04:57 -07:00

71 lines
2.1 KiB
Go

package meta_cache
import (
"context"
"github.com/seaweedfs/seaweedfs/weed/filer"
"github.com/seaweedfs/seaweedfs/weed/glog"
"github.com/seaweedfs/seaweedfs/weed/pb"
"github.com/seaweedfs/seaweedfs/weed/pb/filer_pb"
"github.com/seaweedfs/seaweedfs/weed/util"
)
func SubscribeMetaEvents(mc *MetaCache, selfSignature int32, client filer_pb.FilerClient, dir string, lastTsNs int64) error {
processEventFn := func(resp *filer_pb.SubscribeMetadataResponse) error {
message := resp.EventNotification
for _, sig := range message.Signatures {
if sig == selfSignature && selfSignature != 0 {
return nil
}
}
dir := resp.Directory
var oldPath util.FullPath
var newEntry *filer.Entry
if message.OldEntry != nil {
oldPath = util.NewFullPath(dir, message.OldEntry.Name)
glog.V(4).Infof("deleting %v", oldPath)
}
if message.NewEntry != nil {
if message.NewParentPath != "" {
dir = message.NewParentPath
}
key := util.NewFullPath(dir, message.NewEntry.Name)
glog.V(4).Infof("creating %v", key)
newEntry = filer.FromPbEntry(dir, message.NewEntry)
}
err := mc.AtomicUpdateEntryFromFiler(context.Background(), oldPath, newEntry)
if err == nil {
if message.OldEntry != nil && message.NewEntry != nil {
oldKey := util.NewFullPath(resp.Directory, message.OldEntry.Name)
mc.invalidateFunc(oldKey, message.OldEntry)
if message.OldEntry.Name != message.NewEntry.Name {
newKey := util.NewFullPath(dir, message.NewEntry.Name)
mc.invalidateFunc(newKey, message.NewEntry)
}
} else if filer_pb.IsCreate(resp) {
// no need to invalidate
} else if filer_pb.IsDelete(resp) {
oldKey := util.NewFullPath(resp.Directory, message.OldEntry.Name)
mc.invalidateFunc(oldKey, message.OldEntry)
}
}
return err
}
var clientEpoch int32
util.RetryForever("followMetaUpdates", func() error {
clientEpoch++
return pb.WithFilerClientFollowMetadata(client, "mount", selfSignature, clientEpoch, dir, &lastTsNs, 0, selfSignature, processEventFn, pb.FatalOnError)
}, func(err error) bool {
glog.Errorf("follow metadata updates: %v", err)
return true
})
return nil
}