Golang utils.NewDagEditor函数代码示例

func ImportTar(r io.Reader, ds dag.DAGService) (*dag.Node, error) {
	rall, err := ioutil.ReadAll(r)
	if err != nil {
		return nil, err
	}

	r = bytes.NewReader(rall)

	tr := tar.NewReader(r)

	root := new(dag.Node)
	root.Data = []byte("ipfs/tar")

	e := dagutil.NewDagEditor(root, ds)

	for {
		h, err := tr.Next()
		if err != nil {
			if err == io.EOF {
				break
			}
			return nil, err
		}

		header := new(dag.Node)

		headerBytes, err := marshalHeader(h)
		if err != nil {
			return nil, err
		}

		header.Data = headerBytes

		if h.Size > 0 {
			spl := chunk.NewRabin(tr, uint64(chunk.DefaultBlockSize))
			nd, err := importer.BuildDagFromReader(ds, spl)
			if err != nil {
				return nil, err
			}

			err = header.AddNodeLinkClean("data", nd)
			if err != nil {
				return nil, err
			}
		}

		_, err = ds.Add(header)
		if err != nil {
			return nil, err
		}

		path := escapePath(h.Name)
		err = e.InsertNodeAtPath(context.Background(), path, header, func() *dag.Node { return new(dag.Node) })
		if err != nil {
			return nil, err
		}
	}

	return e.Finalize(ds)
}

// TODO: extract all this logic from the core/commands/object.go to avoid dupe code
func (s *Shell) Patch(root, action string, args ...string) (string, error) {
	p, err := path.ParsePath(root)
	if err != nil {
		return "", err
	}

	rootnd, err := core.Resolve(s.ctx, s.node, p)
	if err != nil {
		return "", err
	}

	insertpath := args[0]
	childhash := args[1]

	childpath, err := path.ParsePath(childhash)
	if err != nil {
		return "", err
	}

	nnode, err := core.Resolve(s.ctx, s.node, childpath)
	if err != nil {
		return "", err
	}

	e := dagutils.NewDagEditor(rootnd, s.node.DAG)

	switch action {
	case "add-link":
		err := e.InsertNodeAtPath(s.ctx, insertpath, nnode, nil)
		if err != nil {
			return "", err
		}

		_, err = e.Finalize(s.node.DAG)
		if err != nil {
			return "", err
		}

		final, err := e.GetNode().Key()
		if err != nil {
			return "", err
		}

		return final.B58String(), nil
	default:
		return "", fmt.Errorf("unsupported action (impl not complete)")
	}
}

func addLinkCaller(req cmds.Request, root *dag.Node) (key.Key, error) {
	if len(req.Arguments()) < 4 {
		return "", fmt.Errorf("not enough arguments for add-link")
	}

	nd, err := req.InvocContext().GetNode()
	if err != nil {
		return "", err
	}

	path := req.Arguments()[2]
	childk := key.B58KeyDecode(req.Arguments()[3])

	create, _, err := req.Option("create").Bool()
	if err != nil {
		return "", err
	}

	var createfunc func() *dag.Node
	if create {
		createfunc = func() *dag.Node {
			return &dag.Node{Data: ft.FolderPBData()}
		}
	}

	e := dagutils.NewDagEditor(nd.DAG, root)

	childnd, err := nd.DAG.Get(req.Context(), childk)
	if err != nil {
		return "", err
	}

	err = e.InsertNodeAtPath(req.Context(), path, childnd, createfunc)
	if err != nil {
		return "", err
	}

	nnode := e.GetNode()

	return nnode.Key()
}

//TODO: hrm, maybe this interface could be better
func (s *Shell) PatchLink(root, npath, childhash string, create bool) (string, error) {
	p, err := path.ParsePath(root)
	if err != nil {
		return "", err
	}

	rootnd, err := core.Resolve(s.ctx, s.node, p)
	if err != nil {
		return "", err
	}

	childpath, err := path.ParsePath(childhash)
	if err != nil {
		return "", err
	}

	nnode, err := core.Resolve(s.ctx, s.node, childpath)
	if err != nil {
		return "", err
	}

	e := dagutils.NewDagEditor(rootnd, s.node.DAG)
	err = e.InsertNodeAtPath(s.ctx, npath, nnode, func() *dag.Node {
		return &dag.Node{Data: ft.FolderPBData()}
	})
	if err != nil {
		return "", err
	}

	_, err = e.Finalize(s.node.DAG)
	if err != nil {
		return "", err
	}

	final, err := e.GetNode().Key()
	if err != nil {
		return "", err
	}

	return final.B58String(), nil
}

func rmLinkCaller(req cmds.Request, root *dag.Node) (key.Key, error) {
	if len(req.Arguments()) < 3 {
		return "", fmt.Errorf("not enough arguments for rm-link")
	}

	nd, err := req.InvocContext().GetNode()
	if err != nil {
		return "", err
	}

	path := req.Arguments()[2]

	e := dagutils.NewDagEditor(nd.DAG, root)

	err = e.RmLink(req.Context(), path)
	if err != nil {
		return "", err
	}

	nnode := e.GetNode()

	return nnode.Key()
}

		// check if repo will exceed storage limit if added
		// TODO: this doesn't handle the case if the hashed file is already in blocks (deduplicated)
		// TODO: conditional GC is disabled due to it is somehow not possible to pass the size to the daemon
		//if err := corerepo.ConditionalGC(req.Context(), n, uint64(size)); err != nil {
		//	res.SetError(err, cmds.ErrNormal)
		//	return
		//}

		progress, _, _ := req.Option(progressOptionName).Bool()
		trickle, _, _ := req.Option(trickleOptionName).Bool()
		wrap, _, _ := req.Option(wrapOptionName).Bool()
		hash, _, _ := req.Option(onlyHashOptionName).Bool()
		hidden, _, _ := req.Option(hiddenOptionName).Bool()
		chunker, _, _ := req.Option(chunkerOptionName).String()

		e := dagutils.NewDagEditor(NewMemoryDagService(), newDirNode())
		if hash {
			nilnode, err := core.NewNode(n.Context(), &core.BuildCfg{
				//TODO: need this to be true or all files
				// hashed will be stored in memory!
				NilRepo: true,
			})
			if err != nil {
				res.SetError(err, cmds.ErrNormal)
				return
			}
			n = nilnode
		}

		outChan := make(chan interface{}, 8)
		res.SetOutput((<-chan interface{})(outChan))

func (i *gatewayHandler) putHandler(w http.ResponseWriter, r *http.Request) {
	// TODO(cryptix): move me to ServeHTTP and pass into all handlers
	ctx, cancel := context.WithCancel(i.node.Context())
	defer cancel()

	rootPath, err := path.ParsePath(r.URL.Path)
	if err != nil {
		webError(w, "putHandler: ipfs path not valid", err, http.StatusBadRequest)
		return
	}

	rsegs := rootPath.Segments()
	if rsegs[0] == ipnsPathPrefix {
		webError(w, "putHandler: updating named entries not supported", errors.New("WritableGateway: ipns put not supported"), http.StatusBadRequest)
		return
	}

	var newnode *dag.Node
	if rsegs[len(rsegs)-1] == "QmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn" {
		newnode = uio.NewEmptyDirectory()
	} else {
		putNode, err := i.newDagFromReader(r.Body)
		if err != nil {
			webError(w, "putHandler: Could not create DAG from request", err, http.StatusInternalServerError)
			return
		}
		newnode = putNode
	}

	var newPath string
	if len(rsegs) > 1 {
		newPath = path.Join(rsegs[2:])
	}

	var newkey key.Key
	rnode, err := core.Resolve(ctx, i.node, rootPath)
	switch ev := err.(type) {
	case path.ErrNoLink:
		// ev.Node < node where resolve failed
		// ev.Name < new link
		// but we need to patch from the root
		rnode, err := i.node.DAG.Get(ctx, key.B58KeyDecode(rsegs[1]))
		if err != nil {
			webError(w, "putHandler: Could not create DAG from request", err, http.StatusInternalServerError)
			return
		}

		e := dagutils.NewDagEditor(rnode, i.node.DAG)
		err = e.InsertNodeAtPath(ctx, newPath, newnode, uio.NewEmptyDirectory)
		if err != nil {
			webError(w, "putHandler: InsertNodeAtPath failed", err, http.StatusInternalServerError)
			return
		}

		nnode, err := e.Finalize(i.node.DAG)
		if err != nil {
			webError(w, "putHandler: could not get node", err, http.StatusInternalServerError)
			return
		}

		newkey, err = nnode.Key()
		if err != nil {
			webError(w, "putHandler: could not get key of edited node", err, http.StatusInternalServerError)
			return
		}

	case nil:
		// object set-data case
		rnode.Data = newnode.Data

		newkey, err = i.node.DAG.Add(rnode)
		if err != nil {
			nnk, _ := newnode.Key()
			rk, _ := rnode.Key()
			webError(w, fmt.Sprintf("putHandler: Could not add newnode(%q) to root(%q)", nnk.B58String(), rk.B58String()), err, http.StatusInternalServerError)
			return
		}
	default:
		log.Warningf("putHandler: unhandled resolve error %T", ev)
		webError(w, "could not resolve root DAG", ev, http.StatusInternalServerError)
		return
	}

	i.addUserHeaders(w) // ok, _now_ write user's headers.
	w.Header().Set("IPFS-Hash", newkey.String())
	http.Redirect(w, r, gopath.Join(ipfsPathPrefix, newkey.String(), newPath), http.StatusCreated)
}

		rootp, err := path.ParsePath(req.Arguments()[0])
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		root, err := core.Resolve(req.Context(), nd, rootp)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		path := req.Arguments()[1]

		e := dagutils.NewDagEditor(root, nd.DAG)

		err = e.RmLink(req.Context(), path)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		nnode, err := e.Finalize(nd.DAG)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		nk, err := nnode.Key()
		if err != nil {

		root, err := core.Resolve(req.Context(), nd.Namesys, nd.Resolver, rootp)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		rtpb, ok := root.(*dag.ProtoNode)
		if !ok {
			res.SetError(dag.ErrNotProtobuf, cmds.ErrNormal)
			return
		}

		path := req.Arguments()[1]

		e := dagutils.NewDagEditor(rtpb, nd.DAG)

		err = e.RmLink(req.Context(), path)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		nnode, err := e.Finalize(nd.DAG)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		nc := nnode.Cid()

				NilRepo: false,
			})
			if err != nil {
				res.SetError(err, cmds.ErrNormal)
				return
			}
			n = nilnode
		}

		outChan := make(chan interface{}, 8)
		res.SetOutput((<-chan interface{})(outChan))

		fileAdder := adder{
			ctx:      req.Context(),
			node:     n,
			editor:   dagutils.NewDagEditor(n.DAG, newDirNode()),
			out:      outChan,
			chunker:  chunker,
			progress: progress,
			hidden:   hidden,
			trickle:  trickle,
			wrap:     wrap,
		}

		// addAllFiles loops over a convenience slice file to
		// add each file individually. e.g. 'ipfs add a b c'
		addAllFiles := func(sliceFile files.File) error {
			for {
				file, err := sliceFile.NextFile()
				if err != nil && err != io.EOF {
					return err