Add CLI tools for debugging and analyzing caching issues

Add the following CLI tools for debugging and analyzing caching issues:
1. checkCaching. Checks if files under a path have been cached in alluxio.
2. location. Displays the list of hosts storing the specified file.
3. consistentHash. This command is for checking whether the consistent hash ring is changed or not.
			pr-link: #18151
			change-id: cid-c89b98da70a5270070d873bdcfce1aa9b23cf083

cli/src/alluxio.org/cli/cmd/fs/check_cached.go

@@ -0,0 +1,67 @@
+/*
+ * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
+ * (the "License"). You may not use this work except in compliance with the License, which is
+ * available at www.apache.org/licenses/LICENSE-2.0
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied, as more fully set forth in the License.
+ *
+ * See the NOTICE file distributed with this work for information regarding copyright ownership.
+ */
+
+package fs
+
+import (
+    "strconv"
+
+    "github.com/spf13/cobra"
+
+    "alluxio.org/cli/env"
+)
+
+func CheckCached(className string) env.Command {
+    return &CheckCachedCommand{
+        BaseJavaCommand: &env.BaseJavaCommand{
+            CommandName:   "check-cached",
+            JavaClassName: className,
+            Parameters:    []string{"check-cached"},
+        },
+    }
+}
+
+type CheckCachedCommand struct {
+    *env.BaseJavaCommand
+
+    sample int
+    limit  int
+}
+
+func (c *CheckCachedCommand) Base() *env.BaseJavaCommand {
+    return c.BaseJavaCommand
+}
+
+func (c *CheckCachedCommand) ToCommand() *cobra.Command {
+    cmd := c.Base().InitRunJavaClassCmd(&cobra.Command{
+        Use:   "check-cached [path]",
+        Short: "Checks if files under a path have been cached in alluxio.",
+        Args:  cobra.ExactArgs(1),
+        RunE: func(cmd *cobra.Command, args []string) error {
+            return c.Run(args)
+        },
+    })
+    cmd.Flags().IntVar(&c.sample, "sample", 1, "Sample ratio, 10 means sample 1 in every 10 files.")
+    cmd.Flags().IntVar(&c.limit, "limit", 1000, "Limit number of files to check")
+    return cmd
+}
+
+func (c *CheckCachedCommand) Run(args []string) error {
+    javaArgs := []string{"check-cached"}
+    if c.sample != 0 {
+        javaArgs = append(javaArgs, "--sample", strconv.Itoa(c.sample))
+    }
+    if c.limit != 0 {
+        javaArgs = append(javaArgs, "--limit", strconv.Itoa(c.limit))
+    }
+    javaArgs = append(javaArgs, args...)
+    return c.Base().Run(javaArgs)
+}

cli/src/alluxio.org/cli/cmd/fs/consistant_hash.go

@@ -0,0 +1,74 @@
+/*
+ * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
+ * (the "License"). You may not use this work except in compliance with the License, which is
+ * available at www.apache.org/licenses/LICENSE-2.0
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied, as more fully set forth in the License.
+ *
+ * See the NOTICE file distributed with this work for information regarding copyright ownership.
+ */
+
+package fs
+
+import (
+    "alluxio.org/cli/env"
+    "github.com/palantir/stacktrace"
+    "github.com/spf13/cobra"
+)
+
+func ConsistentHash(className string) env.Command {
+    return &ConsistentHashCommand{
+        BaseJavaCommand: &env.BaseJavaCommand{
+            CommandName:   "consistent-hash",
+            JavaClassName: className,
+            Parameters:    []string{"consistent-hash"},
+        },
+    }
+}
+
+type ConsistentHashCommand struct {
+    *env.BaseJavaCommand
+
+    createCheckFile   bool
+    compareCheckFiles bool
+    cleanCheckData    bool
+}
+
+func (c *ConsistentHashCommand) Base() *env.BaseJavaCommand {
+    return c.BaseJavaCommand
+}
+
+func (c *ConsistentHashCommand) ToCommand() *cobra.Command {
+    cmd := c.Base().InitRunJavaClassCmd(&cobra.Command{
+        Use:   "consistent-hash [--create]|[--compare <1stCheckFilePath> <2ndCheckFilePath>]|[--clean] ",
+        Short: "This command is for checking whether the consistent hash ring is changed or not",
+        RunE: func(cmd *cobra.Command, args []string) error {
+            return c.Run(args)
+        },
+    })
+    cmd.Flags().BoolVar(&c.createCheckFile, "create", false, "Generate check file.")
+    cmd.Flags().BoolVar(&c.compareCheckFiles, "compare", false, "Compare check files to see if the hash ring has changed and if data lost.")
+    cmd.Flags().BoolVar(&c.cleanCheckData, "clean", false, "Clean all check data.")
+    cmd.MarkFlagsMutuallyExclusive("create", "compare", "clean")
+    return cmd
+}
+
+func (c *ConsistentHashCommand) Run(args []string) error {
+    javaArgs := []string{}
+    if c.createCheckFile {
+        javaArgs = append(javaArgs, "--create")
+    }
+    if c.compareCheckFiles {
+        if len(args) != 2 {
+            return stacktrace.NewError("expect 2 arguments with --compare-check-files but got %v", len(args))
+        }
+        javaArgs = append(javaArgs, "--compare")
+    }
+    if c.cleanCheckData {
+        javaArgs = append(javaArgs, "--clean")
+    }
+
+    javaArgs = append(javaArgs, args...)
+    return c.Base().Run(javaArgs)
+}

cli/src/alluxio.org/cli/cmd/fs/fs.go

@@ -12,37 +12,40 @@
 package fs
 
 import (
-	"alluxio.org/cli/cmd/names"
-	"alluxio.org/cli/env"
+    "alluxio.org/cli/cmd/names"
+    "alluxio.org/cli/env"
 )
 
 var Service = &env.Service{
-	Name:        "fs",
-	Description: "Operations to interface with the Alluxio filesystem",
-	Commands:    Cmds(names.FileSystemShellJavaClass),
+    Name:        "fs",
+    Description: "Operations to interface with the Alluxio filesystem",
+    Commands:    Cmds(names.FileSystemShellJavaClass),
 }
 
 func Cmds(className string) []env.Command {
-	var ret []env.Command
-	for _, c := range []func(string) env.Command{
-		Cat,
-		Checksum,
-		Chgrp,
-		Chmod,
-		Chown,
-		Cp,
-		Head,
-		Ls,
-		Mkdir,
-		Mv,
-		Rm,
-		Stat,
-		Tail,
-		Test,
-		Touch,
-	} {
-		ret = append(ret, c(className))
-	}
+    var ret []env.Command
+    for _, c := range []func(string) env.Command{
+        Cat,
+        Checksum,
+        Chgrp,
+        Chmod,
+        Chown,
+        Cp,
+        Head,
+        Ls,
+        Mkdir,
+        Mv,
+        Rm,
+        Stat,
+        Tail,
+        Test,
+        Touch,
+        Location,
+        CheckCached,
+        ConsistentHash,
+    } {
+        ret = append(ret, c(className))
+    }
 
-	return ret
+    return ret
 }

cli/src/alluxio.org/cli/cmd/fs/location.go

@@ -0,0 +1,52 @@
+/*
+ * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
+ * (the "License"). You may not use this work except in compliance with the License, which is
+ * available at www.apache.org/licenses/LICENSE-2.0
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied, as more fully set forth in the License.
+ *
+ * See the NOTICE file distributed with this work for information regarding copyright ownership.
+ */
+
+package fs
+
+import (
+    "github.com/spf13/cobra"
+
+    "alluxio.org/cli/env"
+)
+
+func Location(className string) env.Command {
+    return &LocationCommand{
+        BaseJavaCommand: &env.BaseJavaCommand{
+            CommandName:   "location",
+            JavaClassName: className,
+            Parameters:    []string{"location"},
+        },
+    }
+}
+
+type LocationCommand struct {
+    *env.BaseJavaCommand
+}
+
+func (c *LocationCommand) Base() *env.BaseJavaCommand {
+    return c.BaseJavaCommand
+}
+
+func (c *LocationCommand) ToCommand() *cobra.Command {
+    cmd := c.Base().InitRunJavaClassCmd(&cobra.Command{
+        Use:   "location [path]",
+        Short: "Displays the list of hosts storing the specified file.",
+        Args:  cobra.ExactArgs(1),
+        RunE: func(cmd *cobra.Command, args []string) error {
+            return c.Run(args)
+        },
+    })
+    return cmd
+}
+
+func (c *LocationCommand) Run(args []string) error {
+    return c.Base().Run(args)
+}

dora/core/client/fs/src/main/java/alluxio/client/file/DelegatingFileSystem.java

@@ -13,6 +13,7 @@
 
 import alluxio.AlluxioURI;
 import alluxio.PositionReader;
+import alluxio.client.file.ufs.UfsBaseFileSystem;
 import alluxio.conf.AlluxioConfiguration;
 import alluxio.exception.AlluxioException;
 import alluxio.exception.DirectoryNotEmptyException;
@@ -50,6 +51,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.function.Consumer;
+import javax.annotation.Nullable;
 
 /**
  * A wrapper of a FileSystem instance.
@@ -260,6 +262,18 @@ public void close() throws IOException {
     mDelegatedFileSystem.close();
   }
 
+  @Nullable
+  @Override
+  public DoraCacheFileSystem getDoraCacheFileSystem() {
+    return mDelegatedFileSystem.getDoraCacheFileSystem();
+  }
+
+  @Nullable
+  @Override
+  public UfsBaseFileSystem getUfsBaseFileSystem() {
+    return mDelegatedFileSystem.getUfsBaseFileSystem();
+  }
+
   /**
    * @return the underlying fileSystem
    */