Implement nodetool history

patch by Stefan Miklosovic; reviewed by Maxim Muzafarov for CASSANDRA-20851

CHANGES.txt

@@ -1,4 +1,5 @@
 5.1
+ * Implement nodetool history (CASSANDRA-20851)
  * Expose StorageService.dropPreparedStatements via JMX (CASSANDRA-20870)
  * Expose Metric for Prepared Statement Cache Size (in bytes) (CASSANDRA-20864)
  * Add support for BEGIN TRANSACTION to allow mutations that touch multiple partitions (CASSANDRA-20857)

src/java/org/apache/cassandra/tools/NodeTool.java

@@ -133,7 +133,7 @@ public class NodeTool
         String cmdLine = Joiner.on(" ").skipNulls().join(args);
         cmdLine = cmdLine.replaceFirst("(?<=(-pw|--password))\\s+\\S+", " <hidden>");
 
-        try (FileWriter writer = new File(FBUtilities.getToolsOutputDirectory(), HISTORYFILE).newWriter(APPEND))
+        try (FileWriter writer = getHistoryFile().newWriter(APPEND))
         {
             SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss,SSS");
             writer.append(sdf.format(new Date())).append(": ").append(cmdLine).append(System.lineSeparator());
@@ -144,6 +144,10 @@ public class NodeTool
         }
     }
 
+    public static File getHistoryFile()
+    {
+        return new File(FBUtilities.getToolsOutputDirectory(), HISTORYFILE);
+    }
 
     public static List<String> getCommandsWithoutRoot(String separator)
     {

src/java/org/apache/cassandra/tools/nodetool/History.java

@@ -0,0 +1,95 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.cassandra.tools.nodetool;
+
+import java.util.List;
+
+import org.apache.cassandra.io.util.File;
+import org.apache.cassandra.io.util.FileUtils;
+import org.apache.cassandra.tools.NodeProbe;
+import org.apache.cassandra.tools.NodeTool;
+import picocli.CommandLine;
+import picocli.CommandLine.Command;
+import picocli.CommandLine.Option;
+
+@Command(name = "history", description = "Print previously executed nodetool commands")
+public class History extends AbstractCommand
+{
+    @Option(paramLabel = "commands",
+    names = { "-n", "--num", "--number-of-commands" },
+    description = "Number of commands to print, defaults to 1000.")
+    public int commands = 1000;
+
+    @Override
+    protected void execute(NodeProbe probe)
+    {
+        if (commands < 1)
+            throw new IllegalArgumentException("Number of commands to display has to be at least 1.");
+
+        File historyFile = getHistoryFile();
+        validateHistoryFile(historyFile);
+
+        for (String line : commandsToPrint(historyFile))
+            output.out.println(line);
+    }
+
+    @Override
+    protected boolean shouldConnect() throws CommandLine.ExecutionException
+    {
+        return false;
+    }
+
+    File getHistoryFile()
+    {
+        return NodeTool.getHistoryFile();
+    }
+
+    List<String> commandsToPrint(File file)
+    {
+        List<String> historyCommands = FileUtils.readLines(file);
+        int size = historyCommands.size();
+        List<String> commandLines;
+
+        if (commands > size)
+            commandLines = historyCommands;
+        else
+            commandLines = historyCommands.subList(size - commands, size);
+
+        return commandLines;
+    }
+
+    /**
+     * Nodetool is appending command to history file before it is executed so us checking on its
+     * existence and validating it is not technically necessary however nodetool is also swallowing
+     * all errors when it was not succesful in appending to the history file so better to check here in that case.
+     *
+     * @param historyFile file to check that it is actually a file which exists and it is readable
+     */
+    void validateHistoryFile(File historyFile)
+    {
+        if (!historyFile.exists())
+            throw new IllegalStateException(String.format("History file %s does not exist.%n", historyFile.absolutePath()));
+
+        if (!historyFile.isFile())
+            throw new IllegalStateException(String.format("History file %s is not a file.%n", historyFile.absolutePath()));
+
+        if (!historyFile.isReadable())
+            throw new IllegalStateException(String.format("History file %s is not readable.%n", historyFile.absolutePath()));
+    }
+}

src/java/org/apache/cassandra/tools/nodetool/NodetoolCommand.java

@@ -128,6 +128,7 @@ import static org.apache.cassandra.tools.nodetool.Help.printTopCommandUsage;
                          GossipInfo.class,
                          GuardrailsConfigCommand.GetGuardrailsConfig.class,
                          GuardrailsConfigCommand.SetGuardrailsConfig.class,
+                         History.class,
                          Import.class,
                          Info.class,
                          InvalidateCIDRPermissionsCache.class,

test/resources/nodetool/help/history

@@ -0,0 +1,31 @@
+NAME
+        nodetool history - Print previously executed nodetool commands
+
+SYNOPSIS
+        nodetool [(-h <host> | --host <host>)] [(-p <port> | --port <port>)]
+                [(-pp | --print-port)] [(-pw <password> | --password <password>)]
+                [(-pwf <passwordFilePath> | --password-file <passwordFilePath>)]
+                [(-u <username> | --username <username>)] history
+                [(-n <commands> | --number-of-commands <commands>)]
+
+OPTIONS
+        -h <host>, --host <host>
+            Node hostname or ip address
+
+        -n <commands>, --num <commands>, --number-of-commands <commands>
+            Number of commands to print, defaults to 1000.
+
+        -p <port>, --port <port>
+            Remote jmx agent port number
+
+        -pp, --print-port
+            Operate in 4.0 mode with hosts disambiguated by port number
+
+        -pw <password>, --password <password>
+            Remote jmx agent password
+
+        -pwf <passwordFilePath>, --password-file <passwordFilePath>
+            Path to the JMX password file
+
+        -u <username>, --username <username>
+            Remote jmx agent username

test/resources/nodetool/help/nodetool

@@ -77,6 +77,7 @@ The most commonly used nodetool commands are:
     gettraceprobability                 Print the current trace probability value
     gossipinfo                          Shows the gossip information for the cluster
     help                                Display help information
+    history                             Print previously executed nodetool commands
     import                              Import new SSTables to the system
     info                                Print node information (uptime, load, ...)
     invalidatecidrpermissionscache      Invalidate the cidr permissions cache

test/unit/org/apache/cassandra/tools/nodetool/HistoryTest.java

@@ -0,0 +1,120 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.cassandra.tools.nodetool;
+
+import java.util.List;
+
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import org.apache.cassandra.io.util.File;
+import org.apache.cassandra.io.util.FileUtils;
+import org.apache.cassandra.tools.Output;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+public class HistoryTest
+{
+    public static File tempHistoryFile = FileUtils.createTempFile("test_nodetool", "history");
+    public static File emptyHistoryFile = FileUtils.createTempFile("test_nodetool_empty", "history");
+    public static List<String> listOfCommands = List.of("oldest command",
+                                                        "older command",
+                                                        "newer command",
+                                                        "newest command");
+
+    @BeforeClass
+    public static void populateHistoryFile()
+    {
+        FileUtils.write(tempHistoryFile, listOfCommands);
+    }
+
+    @Test
+    public void testHistory()
+    {
+        History history = new History()
+        {
+            @Override
+            File getHistoryFile()
+            {
+                return HistoryTest.tempHistoryFile;
+            }
+        };
+
+        history.logger(Output.CONSOLE);
+        File historyFile = history.getHistoryFile();
+
+        assertThat(history.commandsToPrint(historyFile)).containsExactly(listOfCommands.toArray(new String[0]));
+
+        history.commands = 2;
+        assertThat(history.commandsToPrint(historyFile)).containsExactly(listOfCommands.subList(2, listOfCommands.size()).toArray(new String[0]));
+
+        history.commands = 4;
+        assertThat(history.commandsToPrint(historyFile)).containsExactly(listOfCommands.toArray(new String[0]));
+    }
+
+    @Test
+    public void testEmptyHistory()
+    {
+        History history = new History()
+        {
+            @Override
+            File getHistoryFile()
+            {
+                return HistoryTest.emptyHistoryFile;
+            }
+        };
+
+        history.logger(Output.CONSOLE);
+        File historyFile = history.getHistoryFile();
+
+        assertThat(history.commandsToPrint(historyFile)).isEmpty();
+    }
+
+
+    @Test
+    public void testHistoryOutputOnNonExistingHistoryFile()
+    {
+        History history = new History()
+        {
+            @Override
+            File getHistoryFile()
+            {
+                return new File("/does/not/exist");
+            }
+        };
+
+        history.logger(Output.CONSOLE);
+
+        assertThatThrownBy(() -> history.execute(null))
+        .isInstanceOf(IllegalStateException.class)
+        .hasMessage("History file /does/not/exist does not exist.\n");
+    }
+
+    @Test
+    public void testInvalidNumberOfCommandsToPrint()
+    {
+        History history = new History();
+        history.commands = 0;
+
+        assertThatThrownBy(() -> history.execute(null))
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessage("Number of commands to display has to be at least 1.");
+    }
+}