// syncTo syncs the contents in p to all of the shards in urls
// returns the first error if there are multiple
func syncTo(dataRepo string, urls []string) error {
var errs []error
var lock sync.Mutex
addErr := func(err error) {
lock.Lock()
errs = append(errs, err)
lock.Unlock()
}
lr := btrfs.NewLocalReplica(dataRepo)
var wg sync.WaitGroup
for _, url := range urls {
wg.Add(1)
go func(url string) {
defer wg.Done()
sr := newShardReplica(url)
from, err := sr.From()
if err != nil {
addErr(err)
}
err = lr.Pull(from, sr)
if err != nil {
addErr(err)
}
}(url)
}
wg.Wait()
if len(errs) != 0 {
return errs[0]
}
return nil
}
func syncFromUrl(dataRepo string, url string) error {
sr := newShardReplica(url)
lr := btrfs.NewLocalReplica(dataRepo)
from, err := lr.From()
if err != nil {
return err
}
return sr.Pull(from, lr)
}
func (s *shard) Pull(from string, p btrfs.Pusher) error {
return btrfs.NewLocalReplica(s.dataRepo).Pull(from, p)
}
func (s *shard) Push(diff io.Reader) error {
return btrfs.NewLocalReplica(s.dataRepo).Push(diff)
}