// DelBlock deletes the block pointed to by `hash`.
func DelBlock(node *Node, hash gmh.Multihash) error {
nd, err := node.proc()
if err != nil {
log.Warningf("ipfs block-del: %v", err)
return err
}
k := key.B58KeyDecode(hash.B58String())
return nd.Blocks.DeleteBlock(k)
}
// Locate finds the object pointed to by `hash`. It will wait
// for max `timeout` duration if it got less than `n` items in that time.
// If `n` is less than 0, all reachable peers that have `hash` will be returned.
// If `n` is 0, Locate will return immeditately.
// This operation requires online-mode.
func Locate(node *Node, hash gmh.Multihash, n int, t time.Duration) ([]*PeerInfo, error) {
if n == 0 {
return []*PeerInfo{}, nil
}
// Note: Do not use Maxint32. That makes ipfs allocate
// a whole lot of memory. Just assume that 100 is fine.
if n < 0 {
n = 100
}
if !node.IsOnline() {
return nil, ErrIsOffline
}
nd, err := node.proc()
if err != nil {
log.Warningf("ipfs dht: %v", err)
return nil, err
}
dht, ok := nd.Routing.(*ipdht.IpfsDHT)
if !ok {
return nil, commands.ErrNotDHT
}
ctx, cancel := context.WithTimeout(node.Context, t)
defer cancel()
k := key.B58KeyDecode(hash.B58String())
peers := dht.FindProvidersAsync(ctx, k, n)
infos := []*PeerInfo{}
for info := range peers {
// Converting equal struct into each other is my favourite thing.
peerInfo := &PeerInfo{
ID: info.ID.Pretty(),
PubKey: node.ipfsNode.Peerstore.PubKey(info.ID),
}
for _, addr := range info.Addrs {
peerInfo.Addrs = append(peerInfo.Addrs, ma.Cast(addr.Bytes()))
}
infos = append(infos, peerInfo)
}
return infos, nil
}
// CatBlock retuns the data stored in the block pointed to by `hash`.
// It will timeout with util.ErrTimeout if the operation takes too long,
// this includes querying for an non-existing hash.
//
// This operation works offline and online, but if the block is stored
// elsewhere on the net, node must be online to find the block.
func CatBlock(node *Node, hash gmh.Multihash, timeout time.Duration) ([]byte, error) {
nd, err := node.proc()
if err != nil {
log.Warningf("ipfs block-cat: %v", err)
return nil, err
}
ctx, cancel := context.WithTimeout(node.Context, timeout)
defer cancel()
k := key.B58KeyDecode(hash.B58String())
block, err := nd.Blocks.GetBlock(ctx, k)
if err == context.DeadlineExceeded {
return nil, util.ErrTimeout
}
if err != nil {
return nil, err
}
return block.Data(), nil
}
