HDFS-16474. Make HDFS tail tool cross platform (#4157)

* The source files for hdfs_tail
  uses getopt for parsing the
  command line arguments.
* getopt is available only on
  Linux and thus, isn't cross
  platform.
* We need to replace getopt
  with boost::program_options
  to make these tools cross
  platform.

Author: GauthamBanasandra

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/tests/tools/CMakeLists.txt

@@ -40,6 +40,7 @@ add_executable(hdfs_tool_tests
                 hdfs-ls-mock.cc
                 hdfs-setrep-mock.cc
                 hdfs-stat-mock.cc
+                hdfs-tail-mock.cc
                 main.cc)
 target_include_directories(hdfs_tool_tests PRIVATE
                             ../tools
@@ -64,6 +65,7 @@ target_include_directories(hdfs_tool_tests PRIVATE
                             ../../tools/hdfs-ls
                             ../../tools/hdfs-setrep
                             ../../tools/hdfs-stat
+                            ../../tools/hdfs-tail
                             ../../tools/hdfs-cat)
 target_link_libraries(hdfs_tool_tests PRIVATE
                        gmock_main
@@ -87,5 +89,6 @@ target_link_libraries(hdfs_tool_tests PRIVATE
                        hdfs_ls_lib
                        hdfs_setrep_lib
                        hdfs_stat_lib
+                       hdfs_tail_lib
                        hdfs_cat_lib)
 add_test(hdfs_tool_tests hdfs_tool_tests)

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/tests/tools/hdfs-tail-mock.cc

@@ -0,0 +1,64 @@
+/**
+ * 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.
+ */
+
+#include <functional>
+#include <memory>
+#include <string>
+#include <vector>
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "hdfs-tail-mock.h"
+#include "hdfs-tool-tests.h"
+
+namespace hdfs::tools::test {
+TailMock::~TailMock() = default;
+
+void TailMock::SetExpectations(
+    std::function<std::unique_ptr<TailMock>()> test_case,
+    const std::vector<std::string> &args) const {
+  // Get the pointer to the function that defines the test case
+  const auto test_case_func =
+      test_case.target<std::unique_ptr<TailMock> (*)()>();
+  ASSERT_NE(test_case_func, nullptr);
+
+  // Set the expected method calls and their corresponding arguments for each
+  // test case
+  if (*test_case_func == &CallHelp<TailMock>) {
+    EXPECT_CALL(*this, HandleHelp()).Times(1).WillOnce(testing::Return(true));
+    return;
+  }
+
+  if (*test_case_func == &PassAPath<TailMock>) {
+    const auto path = args[0];
+    EXPECT_CALL(*this, HandlePath(path, false))
+        .Times(1)
+        .WillOnce(testing::Return(true));
+  }
+
+  if (*test_case_func == &PassFOptAndAPath<TailMock>) {
+    const auto f_opt = args[0];
+    const auto path = args[1];
+    ASSERT_EQ(f_opt, "-f");
+    EXPECT_CALL(*this, HandlePath(path, true))
+        .Times(1)
+        .WillOnce(testing::Return(true));
+  }
+}
+} // namespace hdfs::tools::test

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/tests/tools/hdfs-tail-mock.h

@@ -0,0 +1,68 @@
+/**
+ * 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.
+ */
+
+#ifndef LIBHDFSPP_TOOLS_HDFS_TAIL_MOCK
+#define LIBHDFSPP_TOOLS_HDFS_TAIL_MOCK
+
+#include <functional>
+#include <memory>
+#include <string>
+#include <vector>
+
+#include <gmock/gmock.h>
+
+#include "hdfs-tail.h"
+
+namespace hdfs::tools::test {
+/**
+ * {@class TailMock} is an {@class Tail} whereby it mocks the
+ * HandleHelp and HandlePath methods for testing their functionality.
+ */
+class TailMock : public hdfs::tools::Tail {
+public:
+  /**
+   * {@inheritdoc}
+   */
+  TailMock(const int argc, char **argv) : Tail(argc, argv) {}
+
+  // Abiding to the Rule of 5
+  TailMock(const TailMock &) = delete;
+  TailMock(TailMock &&) = delete;
+  TailMock &operator=(const TailMock &) = delete;
+  TailMock &operator=(TailMock &&) = delete;
+  ~TailMock() override;
+
+  /**
+   * Defines the methods and the corresponding arguments that are expected
+   * to be called on this instance of {@link HdfsTool} for the given test case.
+   *
+   * @param test_case An {@link std::function} object that points to the
+   * function defining the test case
+   * @param args The arguments that are passed to this test case
+   */
+  void SetExpectations(std::function<std::unique_ptr<TailMock>()> test_case,
+                       const std::vector<std::string> &args = {}) const;
+
+  MOCK_METHOD(bool, HandleHelp, (), (const, override));
+
+  MOCK_METHOD(bool, HandlePath, (const std::string &, const bool),
+              (const, override));
+};
+} // namespace hdfs::tools::test
+
+#endif

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/tests/tools/hdfs-tool-tests.cc

@@ -40,6 +40,7 @@
 #include "hdfs-rm-mock.h"
 #include "hdfs-setrep-mock.h"
 #include "hdfs-stat-mock.h"
+#include "hdfs-tail-mock.h"
 #include "hdfs-tool-test-fixtures.h"
 #include "hdfs-tool-tests.h"
 
@@ -168,6 +169,12 @@ INSTANTIATE_TEST_SUITE_P(
     testing::Values(CallHelp<hdfs::tools::test::StatMock>,
                     PassAPath<hdfs::tools::test::StatMock>));
 
+INSTANTIATE_TEST_SUITE_P(
+    HdfsTail, HdfsToolBasicTest,
+    testing::Values(PassAPath<hdfs::tools::test::TailMock>,
+                    CallHelp<hdfs::tools::test::TailMock>,
+                    PassFOptAndAPath<hdfs::tools::test::TailMock>));
+
 // Negative tests
 INSTANTIATE_TEST_SUITE_P(
     HdfsAllowSnapshot, HdfsToolNegativeTestThrows,
@@ -282,6 +289,20 @@ INSTANTIATE_TEST_SUITE_P(
                     PassMOpt<hdfs::tools::test::StatMock>,
                     PassNOpt<hdfs::tools::test::StatMock>));
 
+INSTANTIATE_TEST_SUITE_P(
+    HdfsTail, HdfsToolNegativeTestThrows,
+    testing::Values(Pass2Paths<hdfs::tools::test::TailMock>,
+                    Pass3Paths<hdfs::tools::test::TailMock>,
+                    PassNOptAndAPath<hdfs::tools::test::TailMock>,
+                    PassRecursiveOwnerAndAPath<hdfs::tools::test::TailMock>,
+                    PassMOpt<hdfs::tools::test::TailMock>,
+                    PassRecursive<hdfs::tools::test::TailMock>,
+                    PassRecursivePath<hdfs::tools::test::TailMock>,
+                    PassNOpt<hdfs::tools::test::TailMock>,
+                    PassOwnerAndAPath<hdfs::tools::test::TailMock>,
+                    PassMPOptsPermissionsAndAPath<hdfs::tools::test::TailMock>,
+                    PassPermissionsAndAPath<hdfs::tools::test::TailMock>));
+
 INSTANTIATE_TEST_SUITE_P(
     HdfsRm, HdfsToolNegativeTestNoThrow,
     testing::Values(PassRecursive<hdfs::tools::test::RmMock>));
@@ -341,3 +362,7 @@ INSTANTIATE_TEST_SUITE_P(
 INSTANTIATE_TEST_SUITE_P(
     HdfsSetrep, HdfsToolNegativeTestNoThrow,
     testing::Values(PassAPath<hdfs::tools::test::SetrepMock>));
+
+INSTANTIATE_TEST_SUITE_P(
+    HdfsTail, HdfsToolNegativeTestNoThrow,
+    testing::Values(PassFOpt<hdfs::tools::test::TailMock>));

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/tests/tools/hdfs-tool-tests.h

@@ -69,6 +69,19 @@ template <class T> std::unique_ptr<T> PassRecursivePath() {
   return hdfs_tool;
 }
 
+template <class T> std::unique_ptr<T> PassFOptAndAPath() {
+  constexpr auto argc = 3;
+  static std::string exe("hdfs_tool_name");
+  static std::string arg1("-f");
+  static std::string arg2("a/b/c");
+
+  static char *argv[] = {exe.data(), arg1.data(), arg2.data()};
+
+  auto hdfs_tool = std::make_unique<T>(argc, argv);
+  hdfs_tool->SetExpectations(PassFOptAndAPath<T>, {arg1, arg2});
+  return hdfs_tool;
+}
+
 template <class T> std::unique_ptr<T> CallHelp() {
   constexpr auto argc = 2;
   static std::string exe("hdfs_tool_name");
@@ -226,6 +239,18 @@ template <class T> std::unique_ptr<T> PassMOpt() {
   return hdfs_tool;
 }
 
+template <class T> std::unique_ptr<T> PassFOpt() {
+  constexpr auto argc = 2;
+  static std::string exe("hdfs_tool_name");
+  static std::string arg1("-f");
+
+  static char *argv[] = {exe.data(), arg1.data()};
+
+  auto hdfs_tool = std::make_unique<T>(argc, argv);
+  hdfs_tool->SetExpectations(PassFOpt<T>, {arg1});
+  return hdfs_tool;
+}
+
 template <class T> std::unique_ptr<T> PassPOptAndPath() {
   constexpr auto argc = 3;
   static std::string exe("hdfs_tool_name");

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/tools/CMakeLists.txt

@@ -34,46 +34,24 @@ add_library(hdfs_tool_obj OBJECT hdfs-tool.cc)
 target_include_directories(hdfs_tool_obj PRIVATE ../tools)
 
 add_subdirectory(hdfs-cat)
-
 add_subdirectory(hdfs-chgrp)
-
 add_subdirectory(hdfs-chown)
-
 add_subdirectory(hdfs-chmod)
-
 add_subdirectory(hdfs-find)
-
 add_subdirectory(hdfs-mkdir)
-
 add_subdirectory(hdfs-rm)
-
 add_subdirectory(hdfs-ls)
-
 add_subdirectory(hdfs-stat)
-
 add_subdirectory(hdfs-count)
-
 add_subdirectory(hdfs-df)
-
 add_subdirectory(hdfs-du)
-
 add_subdirectory(hdfs-get)
-
 add_subdirectory(hdfs-copy-to-local)
-
 add_subdirectory(hdfs-move-to-local)
-
 add_subdirectory(hdfs-setrep)
-
 add_subdirectory(hdfs-allow-snapshot)
-
 add_subdirectory(hdfs-disallow-snapshot)
-
 add_subdirectory(hdfs-create-snapshot)
-
 add_subdirectory(hdfs-rename-snapshot)
-
 add_subdirectory(hdfs-delete-snapshot)
-
-add_executable(hdfs_tail hdfs_tail.cc)
-target_link_libraries(hdfs_tail tools_common hdfspp_static)
+add_subdirectory(hdfs-tail)

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/tools/hdfs-tail/CMakeLists.txt

@@ -0,0 +1,27 @@
+#
+# 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.
+#
+
+add_library(hdfs_tail_lib STATIC $<TARGET_OBJECTS:hdfs_tool_obj> hdfs-tail.cc)
+target_include_directories(hdfs_tail_lib PRIVATE ../../tools ${Boost_INCLUDE_DIRS})
+target_link_libraries(hdfs_tail_lib PRIVATE Boost::boost Boost::program_options tools_common hdfspp_static)
+
+add_executable(hdfs_tail main.cc)
+target_include_directories(hdfs_tail PRIVATE ../../tools)
+target_link_libraries(hdfs_tail PRIVATE hdfs_tail_lib)
+
+install(TARGETS hdfs_tail RUNTIME DESTINATION bin)