Golang zk.ChildrenRecursive函数代码示例

// ExportZkns exports addresses from the VT serving graph to a legacy zkns server.
// Note these functions only work with a zktopo.
func (wr *Wrangler) ExportZkns(ctx context.Context, cell string) error {
	zkTopo, ok := wr.ts.(*zktopo.Server)
	if !ok {
		return fmt.Errorf("ExportZkns only works with zktopo")
	}
	zconn := zkTopo.GetZConn()

	vtNsPath := fmt.Sprintf("/zk/%v/vt/ns", cell)
	zknsRootPath := fmt.Sprintf("/zk/%v/zkns/vt", cell)

	children, err := zk.ChildrenRecursive(zconn, vtNsPath)
	if err != nil {
		return err
	}

	for _, child := range children {
		addrPath := path.Join(vtNsPath, child)
		zknsAddrPath := path.Join(zknsRootPath, child)
		_, stat, err := zconn.Get(addrPath)
		if err != nil {
			return err
		}
		// Leaf nodes correspond to zkns vdns files in the old setup.
		if stat.NumChildren() > 0 {
			continue
		}

		if _, err = wr.exportVtnsToZkns(ctx, zconn, addrPath, zknsAddrPath); err != nil {
			return err
		}
	}
	return nil
}

// ExportZknsForKeyspace exports addresses from the VT serving graph to a legacy zkns server.
func (wr *Wrangler) ExportZknsForKeyspace(ctx context.Context, keyspace string) error {
	zkTopo, ok := wr.ts.(*zktopo.Server)
	if !ok {
		return fmt.Errorf("ExportZknsForKeyspace only works with zktopo")
	}
	zconn := zkTopo.GetZConn()

	shardNames, err := wr.ts.GetShardNames(ctx, keyspace)
	if err != nil {
		return err
	}

	// Scan the first shard to discover which cells need local serving data.
	aliases, err := topo.FindAllTabletAliasesInShard(ctx, wr.ts, keyspace, shardNames[0])
	if err != nil {
		return err
	}

	cellMap := make(map[string]bool)
	for _, alias := range aliases {
		cellMap[alias.Cell] = true
	}

	for cell := range cellMap {
		vtnsRootPath := fmt.Sprintf("/zk/%v/vt/ns/%v", cell, keyspace)
		zknsRootPath := fmt.Sprintf("/zk/%v/zkns/vt/%v", cell, keyspace)

		// Get the existing list of zkns children. If they don't get rewritten,
		// delete them as stale entries.
		zknsChildren, err := zk.ChildrenRecursive(zconn, zknsRootPath)
		if err != nil {
			if zookeeper.IsError(err, zookeeper.ZNONODE) {
				zknsChildren = make([]string, 0)
			} else {
				return err
			}
		}
		staleZknsPaths := make(map[string]bool)
		for _, child := range zknsChildren {
			staleZknsPaths[path.Join(zknsRootPath, child)] = true
		}

		vtnsChildren, err := zk.ChildrenRecursive(zconn, vtnsRootPath)
		if err != nil {
			if zookeeper.IsError(err, zookeeper.ZNONODE) {
				vtnsChildren = make([]string, 0)
			} else {
				return err
			}
		}
		for _, child := range vtnsChildren {
			vtnsAddrPath := path.Join(vtnsRootPath, child)
			zknsAddrPath := path.Join(zknsRootPath, child)

			_, stat, err := zconn.Get(vtnsAddrPath)
			if err != nil {
				return err
			}
			// Leaf nodes correspond to zkns vdns files in the old setup.
			if stat.NumChildren() > 0 {
				continue
			}
			zknsPathsWritten, err := wr.exportVtnsToZkns(ctx, zconn, vtnsAddrPath, zknsAddrPath)
			if err != nil {
				return err
			}
			log.V(6).Infof("zknsPathsWritten: %v", zknsPathsWritten)
			for _, zkPath := range zknsPathsWritten {
				delete(staleZknsPaths, zkPath)
			}
		}
		log.V(6).Infof("staleZknsPaths: %v", staleZknsPaths)
		prunePaths := make([]string, 0, len(staleZknsPaths))
		for prunePath := range staleZknsPaths {
			prunePaths = append(prunePaths, prunePath)
		}
		sort.Strings(prunePaths)
		// Prune paths in reverse order so we remove children first
		for i := len(prunePaths) - 1; i >= 0; i-- {
			log.Infof("prune stale zkns path %v", prunePaths[i])
			if err := zconn.Delete(prunePaths[i], -1); err != nil && !zookeeper.IsError(err, zookeeper.ZNOTEMPTY) {
				return err
			}
		}
	}
	return nil
}

func cmdLs(subFlags *flag.FlagSet, args []string) error {
	var (
		longListing      = subFlags.Bool("l", false, "long listing")
		directoryListing = subFlags.Bool("d", false, "list directory instead of contents")
		force            = subFlags.Bool("f", false, "no warning on nonexistent node")
		recursiveListing = subFlags.Bool("R", false, "recursive listing")
	)
	subFlags.Parse(args)
	if subFlags.NArg() == 0 {
		return fmt.Errorf("ls: no path specified")
	}
	// FIXME(szopa): shadowing?
	resolved, err := zk.ResolveWildcards(zconn, subFlags.Args())
	if err != nil {
		return fmt.Errorf("ls: invalid wildcards: %v", err)
	}
	if len(resolved) == 0 {
		// the wildcards didn't result in anything, we're
		// done.
		return nil
	}

	hasError := false
	needsHeader := len(resolved) > 1 && !*directoryListing
	for _, arg := range resolved {
		zkPath := fixZkPath(arg)
		var children []string
		var err error
		isDir := true
		if *directoryListing {
			children = []string{""}
			isDir = false
		} else if *recursiveListing {
			children, err = zk.ChildrenRecursive(zconn, zkPath)
		} else {
			children, _, err = zconn.Children(zkPath)
			// Assume this is a file node if it has no children.
			if len(children) == 0 {
				children = []string{""}
				isDir = false
			}
		}
		if err != nil {
			hasError = true
			if !*force || !zookeeper.IsError(err, zookeeper.ZNONODE) {
				log.Warningf("ls: cannot access %v: %v", zkPath, err)
			}
		}

		// Show the full path when it helps.
		showFullPath := false
		if *recursiveListing {
			showFullPath = true
		} else if *longListing && (*directoryListing || !isDir) {
			showFullPath = true
		}
		if needsHeader {
			fmt.Printf("%v:\n", zkPath)
		}
		if len(children) > 0 {
			if *longListing && isDir {
				fmt.Printf("total: %v\n", len(children))
			}
			sort.Strings(children)
			stats := make([]zk.Stat, len(children))
			wg := sync.WaitGroup{}
			f := func(i int) {
				localPath := path.Join(zkPath, children[i])
				stat, err := zconn.Exists(localPath)
				if err != nil {
					if !*force || !zookeeper.IsError(err, zookeeper.ZNONODE) {
						log.Warningf("ls: cannot access: %v: %v", localPath, err)
					}
				} else {
					stats[i] = stat
				}
				wg.Done()
			}
			for i := range children {
				wg.Add(1)
				go f(i)
			}
			wg.Wait()

			for i, child := range children {
				localPath := path.Join(zkPath, child)
				if stat := stats[i]; stat != nil {
					fmtPath(stat, localPath, showFullPath, *longListing)
				}
			}
		}
		if needsHeader {
			fmt.Println()
		}
	}
	if hasError {
		return fmt.Errorf("ls: some paths had errors")
	}
	return nil
}

// Store a zk tree in a zip archive. This won't be immediately useful to
// zip tools since even "directories" can contain data.
func cmdZip(subFlags *flag.FlagSet, args []string) error {
	subFlags.Parse(args)
	if subFlags.NArg() < 2 {
		return fmt.Errorf("zip: need to specify source and destination paths")
	}

	dstPath := subFlags.Arg(subFlags.NArg() - 1)
	paths := subFlags.Args()[:len(args)-1]
	if !strings.HasSuffix(dstPath, ".zip") {
		return fmt.Errorf("zip: need to specify destination .zip path: %v", dstPath)
	}

	zipFile, err := os.Create(dstPath)
	if err != nil {
		return fmt.Errorf("zip: error %v", err)
	}

	wg := sync.WaitGroup{}
	items := make(chan *zkItem, 64)
	for _, arg := range paths {
		zkPath := fixZkPath(arg)
		children, err := zk.ChildrenRecursive(zconn, zkPath)
		if err != nil {
			return fmt.Errorf("zip: error %v", err)
		}
		for _, child := range children {
			toAdd := path.Join(zkPath, child)
			wg.Add(1)
			go func() {
				data, stat, err := zconn.Get(toAdd)
				items <- &zkItem{toAdd, data, stat, err}
				wg.Done()
			}()
		}
	}
	go func() {
		wg.Wait()
		close(items)
	}()

	zipWriter := zip.NewWriter(zipFile)
	for item := range items {
		path, data, stat, err := item.path, item.data, item.stat, item.err
		if err != nil {
			return fmt.Errorf("zip: get failed: %v", err)
		}
		// Skip ephemerals - not sure why you would archive them.
		if stat.EphemeralOwner() > 0 {
			continue
		}
		fi := &zip.FileHeader{Name: path, Method: zip.Deflate}
		fi.SetModTime(stat.MTime())
		f, err := zipWriter.CreateHeader(fi)
		if err != nil {
			return fmt.Errorf("zip: create failed: %v", err)
		}
		_, err = f.Write([]byte(data))
		if err != nil {
			return fmt.Errorf("zip: create failed: %v", err)
		}
	}
	err = zipWriter.Close()
	if err != nil {
		return fmt.Errorf("zip: close failed: %v", err)
	}
	zipFile.Close()
	return nil
}

func cmdLs(args []string) {
	if len(args) == 0 {
		log.Fatal("ls: no path specified")
	}
	args, err := zk.ResolveWildcards(zconn, args)
	if err != nil {
		log.Fatalf("ls: invalid wildcards: %v", err)
	}
	if len(args) == 0 {
		// the wildcards didn't result in anything, we're done
		return
	}

	hasError := false
	needsHeader := len(args) > 1 && !*directoryListing
	for _, arg := range args {
		zkPath := fixZkPath(arg)
		var children []string
		var err error
		isDir := true
		if *directoryListing {
			children = []string{""}
			isDir = false
		} else if *recursiveListing {
			children, err = zk.ChildrenRecursive(zconn, zkPath)
		} else {
			children, _, err = zconn.Children(zkPath)
			// Assume this is a file node if it has no children.
			if len(children) == 0 {
				children = []string{""}
				isDir = false
			}
		}
		if err != nil {
			hasError = true
			if !*force || !zookeeper.IsError(err, zookeeper.ZNONODE) {
				log.Printf("ls: cannot access %v: %v", zkPath, err)
			}
		}

		// Show the full path when it helps.
		showFullPath := false
		if *recursiveListing {
			showFullPath = true
		} else if *longListing && (*directoryListing || !isDir) {
			showFullPath = true
		}
		if needsHeader {
			fmt.Printf("%v:\n", zkPath)
		}
		if len(children) > 0 {
			if *longListing && isDir {
				fmt.Printf("total: %v\n", len(children))
			}
			sort.Strings(children)
			stats := make([]zk.Stat, len(children))
			wg := sync.WaitGroup{}
			f := func(i int) {
				localPath := path.Join(zkPath, children[i])
				stat, err := zconn.Exists(localPath)
				if err != nil {
					if !*force || !zookeeper.IsError(err, zookeeper.ZNONODE) {
						log.Printf("ls: cannot access: %v: %v", localPath, err)
					}
				} else {
					stats[i] = stat
				}
				wg.Done()
			}
			for i := range children {
				wg.Add(1)
				go f(i)
			}
			wg.Wait()

			for i, child := range children {
				localPath := path.Join(zkPath, child)
				if stat := stats[i]; stat != nil {
					fmtPath(stat, localPath, showFullPath)
				}
			}
		}
		if needsHeader {
			fmt.Println()
		}
	}
	if hasError {
		os.Exit(1)
	}
}