weed shell: add fs.cd, fs.pwd to change to a directory and print current directory

weed/shell/command_fs_cd.go

@@ -0,0 +1,99 @@
+package shell
+
+import (
+	"context"
+	"fmt"
+	"github.com/chrislusf/seaweedfs/weed/filer2"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"io"
+	"strings"
+)
+
+func init() {
+	commands = append(commands, &commandFsCd{})
+}
+
+type commandFsCd struct {
+}
+
+func (c *commandFsCd) Name() string {
+	return "fs.cd"
+}
+
+func (c *commandFsCd) Help() string {
+	return `change directory to http://<filer_server>:<port>/dir/
+
+	The full path can be too long to type. For example,
+		fs.ls http://<filer_server>:<port>/some/path/to/file_name
+
+	can be simplified as
+
+		fs.cd http://<filer_server>:<port>/some/path
+		fs.ls to/file_name
+`
+}
+
+func (c *commandFsCd) Do(args []string, commandEnv *commandEnv, writer io.Writer) (err error) {
+
+	input := ""
+	if len(args) > 0 {
+		input = args[len(args)-1]
+	}
+
+	filerServer, filerPort, path, err := commandEnv.parseUrl(input)
+	if err != nil {
+		return err
+	}
+
+	dir, name := filer2.FullPath(path).DirAndName()
+	if strings.HasSuffix(path, "/") {
+		if path == "/" {
+			dir, name = "/", ""
+		} else {
+			dir, name = filer2.FullPath(path[0:len(path)-1]).DirAndName()
+		}
+	}
+
+	ctx := context.Background()
+
+	err = commandEnv.withFilerClient(ctx, filerServer, filerPort, func(client filer_pb.SeaweedFilerClient) error {
+
+		resp, listErr := client.ListEntries(ctx, &filer_pb.ListEntriesRequest{
+			Directory:          dir,
+			Prefix:             name,
+			StartFromFileName:  name,
+			InclusiveStartFrom: true,
+			Limit:              1,
+		})
+		if listErr != nil {
+			return listErr
+		}
+
+		if path == "" || path == "/" {
+			return nil
+		}
+
+		if len(resp.Entries) == 0 {
+			return fmt.Errorf("entry not found")
+		}
+
+		if resp.Entries[0].Name != name {
+			println("path", path, "dir", dir, "name", name, "found", resp.Entries[0].Name)
+			return fmt.Errorf("not a valid directory, found %s", resp.Entries[0].Name)
+		}
+
+		if !resp.Entries[0].IsDirectory {
+			return fmt.Errorf("not a directory")
+		}
+
+		return nil
+	})
+
+	if err == nil {
+		commandEnv.option.FilerHost = filerServer
+		commandEnv.option.FilerPort = filerPort
+		commandEnv.option.Directory = path
+	}
+
+	return err
+}