Golang key.Key函數代碼示例

func Diff(ctx context.Context, ds dag.DAGService, a, b *dag.Node) []*Change {
	if len(a.Links) == 0 && len(b.Links) == 0 {
		ak, _ := a.Key()
		bk, _ := b.Key()
		return []*Change{
			&Change{
				Type:   Mod,
				Before: ak,
				After:  bk,
			},
		}
	}

	var out []*Change
	clean_a := a.Copy()
	clean_b := b.Copy()

	// strip out unchanged stuff
	for _, lnk := range a.Links {
		l, err := b.GetNodeLink(lnk.Name)
		if err == nil {
			if bytes.Equal(l.Hash, lnk.Hash) {
				// no change... ignore it
			} else {
				anode, _ := lnk.GetNode(ctx, ds)
				bnode, _ := l.GetNode(ctx, ds)
				sub := Diff(ctx, ds, anode, bnode)

				for _, subc := range sub {
					subc.Path = path.Join(lnk.Name, subc.Path)
					out = append(out, subc)
				}
			}
			clean_a.RemoveNodeLink(l.Name)
			clean_b.RemoveNodeLink(l.Name)
		}
	}

	for _, lnk := range clean_a.Links {
		out = append(out, &Change{
			Type:   Remove,
			Path:   lnk.Name,
			Before: key.Key(lnk.Hash),
		})
	}
	for _, lnk := range clean_b.Links {
		out = append(out, &Change{
			Type:  Add,
			Path:  lnk.Name,
			After: key.Key(lnk.Hash),
		})
	}

	return out
}

// resolveOnce implements resolver. Uses the IPFS routing system to
// resolve SFS-like names.
func (r *routingResolver) resolveOnce(ctx context.Context, name string) (path.Path, error) {
	log.Debugf("RoutingResolve: '%s'", name)
	hash, err := mh.FromB58String(name)
	if err != nil {
		log.Warning("RoutingResolve: bad input hash: [%s]\n", name)
		return "", err
	}
	// name should be a multihash. if it isn't, error out here.

	// use the routing system to get the name.
	// /ipns/<name>
	h := []byte("/ipns/" + string(hash))

	ipnsKey := key.Key(h)
	val, err := r.routing.GetValue(ctx, ipnsKey)
	if err != nil {
		log.Warning("RoutingResolve get failed.")
		return "", err
	}

	entry := new(pb.IpnsEntry)
	err = proto.Unmarshal(val, entry)
	if err != nil {
		return "", err
	}

	// name should be a public key retrievable from ipfs
	pubkey, err := routing.GetPublicKey(r.routing, ctx, hash)
	if err != nil {
		return "", err
	}

	hsh, _ := pubkey.Hash()
	log.Debugf("pk hash = %s", key.Key(hsh))

	// check sig with pk
	if ok, err := pubkey.Verify(ipnsEntryDataForSig(entry), entry.GetSignature()); err != nil || !ok {
		return "", fmt.Errorf("Invalid value. Not signed by PrivateKey corresponding to %v", pubkey)
	}

	// ok sig checks out. this is a valid name.

	// check for old style record:
	valh, err := mh.Cast(entry.GetValue())
	if err != nil {
		// Not a multihash, probably a new record
		return path.ParsePath(string(entry.GetValue()))
	} else {
		// Its an old style multihash record
		log.Warning("Detected old style multihash record")
		return path.FromKey(key.Key(valh)), nil
	}
}

func (rw *RefWriter) writeRefsRecursive(n *dag.Node) (int, error) {
	nkey, err := n.Key()
	if err != nil {
		return 0, err
	}

	var count int
	for i, ng := range rw.DAG.GetDAG(rw.Ctx, n) {
		lk := key.Key(n.Links[i].Hash)
		if rw.skip(lk) {
			continue
		}

		if err := rw.WriteEdge(nkey, lk, n.Links[i].Name); err != nil {
			return count, err
		}

		nd, err := ng.Get(rw.Ctx)
		if err != nil {
			return count, err
		}

		c, err := rw.writeRefsRecursive(nd)
		count += c
		if err != nil {
			return count, err
		}
	}
	return count, nil
}

func (dht *IpfsDHT) handleAddProvider(ctx context.Context, p peer.ID, pmes *pb.Message) (*pb.Message, error) {
	lm := make(lgbl.DeferredMap)
	lm["peer"] = func() interface{} { return p.Pretty() }

	defer log.EventBegin(ctx, "handleAddProvider", lm).Done()
	key := key.Key(pmes.GetKey())
	lm["key"] = func() interface{} { return key.Pretty() }

	log.Debugf("%s adding %s as a provider for '%s'\n", dht.self, p, key)

	// add provider should use the address given in the message
	pinfos := pb.PBPeersToPeerInfos(pmes.GetProviderPeers())
	for _, pi := range pinfos {
		if pi.ID != p {
			// we should ignore this provider reccord! not from originator.
			// (we chould sign them and check signature later...)
			log.Debugf("handleAddProvider received provider %s from %s. Ignore.", pi.ID, p)
			continue
		}

		if len(pi.Addrs) < 1 {
			log.Debugf("%s got no valid addresses for provider %s. Ignore.", dht.self, p)
			continue
		}

		log.Infof("received provider %s for %s (addrs: %s)", p, key, pi.Addrs)
		if pi.ID != dht.self { // dont add own addrs.
			// add the received addresses to our peerstore.
			dht.peerstore.AddAddrs(pi.ID, pi.Addrs, peer.ProviderAddrTTL)
		}
		dht.providers.AddProvider(ctx, key, p)
	}

	return nil, nil
}

// putProvider sends a message to peer 'p' saying that the local node
// can provide the value of 'key'
func (dht *IpfsDHT) putProvider(ctx context.Context, p peer.ID, skey string) error {

	// add self as the provider
	pi := peer.PeerInfo{
		ID:    dht.self,
		Addrs: dht.host.Addrs(),
	}

	// // only share WAN-friendly addresses ??
	// pi.Addrs = addrutil.WANShareableAddrs(pi.Addrs)
	if len(pi.Addrs) < 1 {
		// log.Infof("%s putProvider: %s for %s error: no wan-friendly addresses", dht.self, p, key.Key(key), pi.Addrs)
		return fmt.Errorf("no known addresses for self. cannot put provider.")
	}

	pmes := pb.NewMessage(pb.Message_ADD_PROVIDER, skey, 0)
	pmes.ProviderPeers = pb.RawPeerInfosToPBPeers([]peer.PeerInfo{pi})
	err := dht.sendMessage(ctx, p, pmes)
	if err != nil {
		return err
	}

	log.Debugf("%s putProvider: %s for %s (%s)", dht.self, p, key.Key(skey), pi.Addrs)
	return nil
}

func defaultRepo(dstore ds.ThreadSafeDatastore) (repo.Repo, error) {
	c := cfg.Config{}
	priv, pub, err := ci.GenerateKeyPairWithReader(ci.RSA, 1024, rand.Reader)
	if err != nil {
		return nil, err
	}

	data, err := pub.Hash()
	if err != nil {
		return nil, err
	}

	privkeyb, err := priv.Bytes()
	if err != nil {
		return nil, err
	}

	c.Bootstrap = cfg.DefaultBootstrapAddresses
	c.Addresses.Swarm = []string{"/ip4/0.0.0.0/tcp/4001"}
	c.Identity.PeerID = key.Key(data).B58String()
	c.Identity.PrivKey = base64.StdEncoding.EncodeToString(privkeyb)

	return &repo.Mock{
		D: dstore,
		C: c,
	}, nil
}

// NewFilesystem instantiates an ipns filesystem using the given parameters and locally owned keys
func NewFilesystem(ctx context.Context, ds dag.DAGService, nsys namesys.NameSystem, pins pin.Pinner, keys ...ci.PrivKey) (*Filesystem, error) {
	roots := make(map[string]*KeyRoot)
	fs := &Filesystem{
		ctx:      ctx,
		roots:    roots,
		nsys:     nsys,
		dserv:    ds,
		pins:     pins,
		resolver: &path.Resolver{DAG: ds},
	}
	for _, k := range keys {
		pkh, err := k.GetPublic().Hash()
		if err != nil {
			return nil, err
		}

		root, err := fs.newKeyRoot(ctx, k)
		if err != nil {
			return nil, err
		}
		roots[key.Key(pkh).Pretty()] = root
	}

	return fs, nil
}

// VerifyRecord checks a record and ensures it is still valid.
// It runs needed validators
func (v Validator) VerifyRecord(r *pb.Record) error {
	// Now, check validity func
	parts := strings.Split(r.GetKey(), "/")
	if len(parts) < 3 {
		log.Infof("Record key does not have validator: %s", key.Key(r.GetKey()))
		return nil
	}

	val, ok := v[parts[1]]
	if !ok {
		log.Infof("Unrecognized key prefix: %s", parts[1])
		return ErrInvalidRecordType
	}

	return val.Func(key.Key(r.GetKey()), r.GetValue())
}

// newKeyRoot creates a new KeyRoot for the given key, and starts up a republisher routine
// for it
func (fs *Filesystem) newKeyRoot(parent context.Context, k ci.PrivKey) (*KeyRoot, error) {
	hash, err := k.GetPublic().Hash()
	if err != nil {
		return nil, err
	}

	name := "/ipns/" + key.Key(hash).String()

	root := new(KeyRoot)
	root.key = k
	root.fs = fs
	root.name = name

	ctx, cancel := context.WithCancel(parent)
	defer cancel()

	pointsTo, err := fs.nsys.Resolve(ctx, name)
	if err != nil {
		err = namesys.InitializeKeyspace(ctx, fs.dserv, fs.nsys, fs.pins, k)
		if err != nil {
			return nil, err
		}

		pointsTo, err = fs.nsys.Resolve(ctx, name)
		if err != nil {
			return nil, err
		}
	}

	mnode, err := fs.resolver.ResolvePath(ctx, pointsTo)
	if err != nil {
		log.Errorf("Failed to retrieve value '%s' for ipns entry: %s\n", pointsTo, err)
		return nil, err
	}

	root.node = mnode

	root.repub = NewRepublisher(root, time.Millisecond*300, time.Second*3)
	go root.repub.Run(parent)

	pbn, err := ft.FromBytes(mnode.Data)
	if err != nil {
		log.Error("IPNS pointer was not unixfs node")
		return nil, err
	}

	switch pbn.GetType() {
	case ft.TDirectory:
		root.val = NewDirectory(ctx, pointsTo.String(), mnode, root, fs)
	case ft.TFile, ft.TMetadata, ft.TRaw:
		fi, err := NewFile(pointsTo.String(), mnode, root, fs)
		if err != nil {
			return nil, err
		}
		root.val = fi
	default:
		panic("unrecognized! (NYI)")
	}
	return root, nil
}

func (rw *RefWriter) writeRefsSingle(n *dag.Node) (int, error) {
	nkey, err := n.Key()
	if err != nil {
		return 0, err
	}

	if rw.skip(nkey) {
		return 0, nil
	}

	count := 0
	for _, l := range n.Links {
		lk := key.Key(l.Hash)

		if rw.skip(lk) {
			continue
		}

		if err := rw.WriteEdge(nkey, lk, l.Name); err != nil {
			return count, err
		}
		count++
	}
	return count, nil
}

func publish(ctx context.Context, n *core.IpfsNode, k crypto.PrivKey, ref path.Path, opts *publishOpts) (*IpnsEntry, error) {

	if opts.verifyExists {
		// verify the path exists
		_, err := core.Resolve(ctx, n, ref)
		if err != nil {
			return nil, err
		}
	}

	eol := time.Now().Add(opts.pubValidTime)
	err := n.Namesys.PublishWithEOL(ctx, k, ref, eol)
	if err != nil {
		return nil, err
	}

	hash, err := k.GetPublic().Hash()
	if err != nil {
		return nil, err
	}

	return &IpnsEntry{
		Name:  key.Key(hash).String(),
		Value: ref.String(),
	}, nil
}

// GetDAG will fill out all of the links of the given Node.
// It returns a channel of nodes, which the caller can receive
// all the child nodes of 'root' on, in proper order.
func (ds *dagService) GetDAG(ctx context.Context, root *Node) []NodeGetter {
	var keys []key.Key
	for _, lnk := range root.Links {
		keys = append(keys, key.Key(lnk.Hash))
	}

	return ds.GetNodes(ctx, keys)
}

// Removes the child node at the given index
func (n *UnixfsNode) RemoveChild(index int, dbh *DagBuilderHelper) {
	k := key.Key(n.node.Links[index].Hash)
	if dbh.mp != nil {
		dbh.mp.RemovePinWithMode(k, pin.Indirect)
	}
	n.ufmt.RemoveBlockSize(index)
	n.node.Links = append(n.node.Links[:index], n.node.Links[index+1:]...)
}

// Loggable turns a Message into machine-readable log output
func (m *Message) Loggable() map[string]interface{} {
	return map[string]interface{}{
		"message": map[string]string{
			"type": m.Type.String(),
			"key":  key.Key(m.GetKey()).Pretty(),
		},
	}
}

func newMessageFromProto(pbm pb.Message) BitSwapMessage {
	m := newMsg(pbm.GetWantlist().GetFull())
	for _, e := range pbm.GetWantlist().GetEntries() {
		m.addEntry(key.Key(e.GetBlock()), int(e.GetPriority()), e.GetCancel())
	}
	for _, d := range pbm.GetBlocks() {
		b := blocks.NewBlock(d)
		m.AddBlock(b)
	}
	return m
}