// AllKeysChan runs a query for keys from the blockstore.
// this is very simplistic, in the future, take dsq.Query as a param?
//
// AllKeysChan respects context
func (bs *blockstore) AllKeysChan(ctx context.Context) (<-chan *cid.Cid, error) {
// KeysOnly, because that would be _a lot_ of data.
q := dsq.Query{KeysOnly: true}
// datastore/namespace does *NOT* fix up Query.Prefix
q.Prefix = BlockPrefix.String()
res, err := bs.datastore.Query(q)
if err != nil {
return nil, err
}
output := make(chan *cid.Cid, dsq.KeysOnlyBufSize)
go func() {
defer func() {
res.Close() // ensure exit (signals early exit, too)
close(output)
}()
for {
e, ok := res.NextSync()
if !ok {
return
}
if e.Error != nil {
log.Errorf("blockstore.AllKeysChan got err:", e.Error)
return
}
// need to convert to key.Key using key.KeyFromDsKey.
k, err := dshelp.DsKeyToCid(ds.RawKey(e.Key))
if err != nil {
log.Warningf("error parsing key from DsKey: ", err)
continue
}
select {
case <-ctx.Done():
return
case output <- k:
}
}
}()
return output, nil
}
// AllKeysChan runs a query for keys from the blockstore.
// this is very simplistic, in the future, take dsq.Query as a param?
//
// AllKeysChan respects context
func (bs *blockstore) AllKeysChan(ctx context.Context) (<-chan *cid.Cid, error) {
// KeysOnly, because that would be _a lot_ of data.
q := dsq.Query{KeysOnly: true}
// datastore/namespace does *NOT* fix up Query.Prefix
q.Prefix = BlockPrefix.String()
res, err := bs.datastore.Query(q)
if err != nil {
return nil, err
}
// this function is here to compartmentalize
get := func() (*cid.Cid, bool) {
select {
case <-ctx.Done():
return nil, false
case e, more := <-res.Next():
if !more {
return nil, false
}
if e.Error != nil {
log.Debug("blockstore.AllKeysChan got err:", e.Error)
return nil, false
}
// need to convert to key.Key using key.KeyFromDsKey.
c, err := dshelp.DsKeyStringToCid(e.Key)
if err != nil {
log.Warningf("error parsing key from DsKey: ", err)
return nil, true
}
return c, true
}
}
output := make(chan *cid.Cid, dsq.KeysOnlyBufSize)
go func() {
defer func() {
res.Process().Close() // ensure exit (signals early exit, too)
close(output)
}()
for {
k, ok := get()
if !ok {
return
}
if k == nil {
continue
}
select {
case <-ctx.Done():
return
case output <- k:
}
}
}()
return output, nil
}