Add tee command for pipes (alibaba#976)

Author: yamyay

core/src/main/java/com/taobao/arthas/core/command/BuiltinCommandPack.java

@@ -13,6 +13,7 @@
 import com.taobao.arthas.core.command.basic1000.StopCommand;
 import com.taobao.arthas.core.command.basic1000.SystemEnvCommand;
 import com.taobao.arthas.core.command.basic1000.SystemPropertyCommand;
+import com.taobao.arthas.core.command.basic1000.TeeCommand;
 import com.taobao.arthas.core.command.basic1000.VMOptionCommand;
 import com.taobao.arthas.core.command.basic1000.VersionCommand;
 import com.taobao.arthas.core.command.hidden.JulyCommand;
@@ -102,6 +103,7 @@ private static void initCommands() {
         commands.add(Command.create(PwdCommand.class));
         commands.add(Command.create(MBeanCommand.class));
         commands.add(Command.create(GrepCommand.class));
+        commands.add(Command.create(TeeCommand.class));
         commands.add(Command.create(ProfilerCommand.class));
     }
 }

core/src/main/java/com/taobao/arthas/core/command/basic1000/TeeCommand.java

@@ -0,0 +1,48 @@
+package com.taobao.arthas.core.command.basic1000;
+
+
+import com.taobao.arthas.core.command.Constants;
+import com.taobao.arthas.core.shell.command.AnnotatedCommand;
+import com.taobao.arthas.core.shell.command.CommandProcess;
+import com.taobao.middleware.cli.annotations.*;
+
+/**
+ * @author min.yang
+ */
+@Name("tee")
+@Summary("tee command for pipes." )
+@Description(Constants.EXAMPLE +
+        " sysprop | tee /path/to/logfile | grep java \n" +
+        " sysprop | tee -a /path/to/logfile | grep java \n"
+        + Constants.WIKI + Constants.WIKI_HOME + "tee")
+public class TeeCommand extends AnnotatedCommand {
+
+    private String filePath;
+    private boolean append;
+
+    @Argument(index = 0, argName = "file", required = false)
+    @Description("File path")
+    public void setFilePath(String filePath) {
+        this.filePath = filePath;
+    }
+
+    @Option(shortName = "a", longName = "append", flag = true)
+    @Description("Append to file")
+    public void setRegEx(boolean append) {
+        this.append = append;
+    }
+
+    @Override
+    public void process(CommandProcess process) {
+        process.write("The tee command only for pipes. See 'tee --help'\n");
+        process.end();
+    }
+
+    public String getFilePath() {
+        return filePath;
+    }
+
+    public boolean isAppend() {
+        return append;
+    }
+}

core/src/main/java/com/taobao/arthas/core/shell/command/internal/StdoutHandler.java

@@ -30,7 +30,9 @@ public static StdoutHandler inject(List<CliToken> tokens) {
             return PlainTextHandler.inject(tokens);
         } else if (firstTextToken.value().equals(WordCountHandler.NAME)) {
             return WordCountHandler.inject(tokens);
-        } else {
+        } else if (firstTextToken.value().equals(TeeHandler.NAME)){
+            return TeeHandler.inject(tokens);
+        } else{
             return null;
         }
     }

core/src/main/java/com/taobao/arthas/core/shell/command/internal/TeeHandler.java

@@ -0,0 +1,80 @@
+package com.taobao.arthas.core.shell.command.internal;
+
+import com.taobao.arthas.core.command.basic1000.TeeCommand;
+import com.taobao.arthas.core.shell.cli.CliToken;
+import com.taobao.arthas.core.util.StringUtils;
+import com.taobao.middleware.cli.CLI;
+import com.taobao.middleware.cli.CommandLine;
+import com.taobao.middleware.cli.annotations.CLIConfigurator;
+
+import java.io.*;
+import java.util.List;
+
+/**
+ * @author min.yang
+ */
+public class TeeHandler extends StdoutHandler implements CloseFunction {
+    public static final String NAME = "tee";
+    private PrintWriter out;
+    private static CLI cli = null;
+
+    public TeeHandler(String filePath, boolean append) throws IOException {
+        if (StringUtils.isEmpty(filePath)) {
+            return;
+        }
+        File file = new File(filePath);
+
+        if (file.isDirectory()) {
+            throw new IOException(filePath + ": Is a directory");
+        }
+
+        if (!file.exists()) {
+            File parentFile = file.getParentFile();
+            if (parentFile != null) {
+                parentFile.mkdirs();
+            }
+        }
+        out = new PrintWriter(new BufferedWriter(new FileWriter(file, append)));
+    }
+
+    public static StdoutHandler inject(List<CliToken> tokens) {
+        List<String> args = StdoutHandler.parseArgs(tokens, NAME);
+
+        TeeCommand teeCommand = new TeeCommand();
+        if (cli == null) {
+            cli = CLIConfigurator.define(TeeCommand.class);
+        }
+        CommandLine commandLine = cli.parse(args, true);
+
+        try {
+            CLIConfigurator.inject(commandLine, teeCommand);
+        } catch (Throwable e) {
+            throw new RuntimeException(e);
+        }
+
+        String filePath = teeCommand.getFilePath();
+        boolean append = teeCommand.isAppend();
+        try {
+            return new TeeHandler(filePath, append);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public String apply(String data) {
+        data = super.apply(data);
+        if (out != null) {
+            out.write(data);
+            out.flush();
+        }
+        return data;
+    }
+
+    @Override
+    public void close() {
+        if (out != null) {
+            out.close();
+        }
+    }
+}

site/src/site/sphinx/en/tee.md

@@ -0,0 +1,25 @@
+tee
+===
+
+> Similar to the traditional `tee` command.
+
+
+```
+ USAGE:
+   tee [-a] [-h] [file]
+
+ SUMMARY:
+   tee command for pipes.
+
+ EXAMPLES:
+  sysprop | tee /path/to/logfile | grep java
+  sysprop | tee -a /path/to/logfile | grep java
+
+ WIKI:
+   https://alibaba.github.io/arthas/tee
+
+ OPTIONS:
+ -a, --append                              Append to file
+ -h, --help                                this help
+ <file>                                    File path
+```

site/src/site/sphinx/tee.md

@@ -0,0 +1,25 @@
+tee
+===
+
+> 类似传统的`tee`命令。
+
+
+```
+ USAGE:
+   tee [-a] [-h] [file]
+
+ SUMMARY:
+   tee command for pipes.
+
+ EXAMPLES:
+  sysprop | tee /path/to/logfile | grep java
+  sysprop | tee -a /path/to/logfile | grep java
+
+ WIKI:
+   https://alibaba.github.io/arthas/tee
+
+ OPTIONS:
+ -a, --append                              Append to file
+ -h, --help                                this help
+ <file>                                    File path
+```