// 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 <mesos/module.hpp>

#include <mesos/module/hook.hpp>
#include <mesos/module/isolator.hpp>
#include <mesos/module/module.hpp>

#include <mesos/slave/isolator.hpp>

#include <stout/dynamiclibrary.hpp>
#include <stout/os.hpp>
#include <stout/path.hpp>
#include <stout/stringify.hpp>

#include "common/parse.hpp"
#include "examples/test_module.hpp"
#include "module/manager.hpp"

#include "tests/flags.hpp"
#include "tests/mesos.hpp"

using std::string;

using namespace mesos::internal::slave;
using namespace mesos::modules;

using mesos::slave::Isolator;

namespace mesos {
namespace internal {
namespace tests {

const char* DEFAULT_MODULE_LIBRARY_NAME = "examplemodule";
const char* DEFAULT_MODULE_NAME = "org_apache_mesos_TestModule";


class ModuleTest : public MesosTest
{
protected:
  // During the one-time setup of the test cases, we dlopen() the examplemodule
  // library and retrieve the pointer to ModuleBase for the test module. This
  // pointer is later used to reset the Mesos and module API versions during
  // per-test teardown.
  static void SetUpTestCase()
  {
    MesosTest::SetUpTestCase();

    EXPECT_SOME(dynamicLibrary.open(
        getModulePath(DEFAULT_MODULE_LIBRARY_NAME)));

    Try<void*> symbol = dynamicLibrary.loadSymbol(DEFAULT_MODULE_NAME);
    EXPECT_SOME(symbol);

    moduleBase = static_cast<ModuleBase*>(symbol.get());
  }

  static void TearDownTestCase()
  {
    MesosTest::TearDownTestCase();

    // Close the module library.
    dynamicLibrary.close();
  }

  ModuleTest()
    : module(None())
  {
    Modules::Library* library = defaultModules.add_libraries();
    library->set_file(getModulePath(DEFAULT_MODULE_LIBRARY_NAME));
    library->add_modules()->set_name(DEFAULT_MODULE_NAME);
  }

  // During the per-test tear-down, we unload the module to allow
  // later loads to succeed.
  ~ModuleTest() override
  {
    // The TestModule instance is created by calling new. Let's
    // delete it to avoid memory leaks.
    if (module.isSome()) {
      delete module.get();
    }

    // Reset module API version and Mesos version in case the test
    // changed them.
    moduleBase->kind = "TestModule";
    moduleBase->moduleApiVersion = MESOS_MODULE_API_VERSION;
    moduleBase->mesosVersion = MESOS_VERSION;

    // Unload the module so a subsequent loading may succeed.
    ModuleManager::unload(DEFAULT_MODULE_NAME);
  }

  Modules defaultModules;
  Result<TestModule*> module;

  static DynamicLibrary dynamicLibrary;
  static ModuleBase* moduleBase;
};


DynamicLibrary ModuleTest::dynamicLibrary;
ModuleBase* ModuleTest::moduleBase = nullptr;


Modules getModules(
    const string& libraryName,
    const string& moduleName)
{
  Modules modules;
  Modules::Library* library = modules.add_libraries();
  library->set_file(getModulePath(libraryName));
  Modules::Library::Module* module = library->add_modules();
  module->set_name(moduleName);
  return modules;
}


Modules getModules(
    const string& libraryName,
    const string& moduleName,
    const string& parameterKey,
    const string& parameterValue)
{
  Modules modules = getModules(libraryName, moduleName);
  Modules::Library* library = modules.mutable_libraries(0);
  Modules::Library::Module* module = library->mutable_modules(0);
  Parameter* parameter = module->add_parameters();
  parameter->set_key(parameterKey);
  parameter->set_value(parameterValue);
  return modules;
}


Try<Modules> getModulesFromJson(
    const string& libraryName,
    const string& moduleName,
    const string& parameterKey,
    const string& parameterValue)
{
  string libraryFile = getModulePath(libraryName);

  string jsonString =
    "{\n"
    "  \"libraries\": [\n"
    "    {\n"
    "      \"file\": \"" + libraryFile + "\",\n"
    "      \"modules\": [\n"
    "        {\n"
    "          \"name\": \"" + moduleName + "\",\n"
    "          \"parameters\": [\n"
    "            {\n"
    "              \"key\": \"" + parameterKey + "\",\n"
    "              \"value\": \"" + parameterValue + "\"\n"
    "            }\n"
    "          ]\n"
    "        }\n"
    "      ]\n"
    "    }\n"
    "  ]\n"
    "}";

  return flags::parse<Modules>(jsonString);
}


// Test that a module library gets loaded, and its contents
// version-verified. The provided test library matches the current
// Mesos version exactly.
TEST_F(ModuleTest, ExampleModuleLoadTest)
{
  EXPECT_SOME(ModuleManager::load(defaultModules));

  EXPECT_TRUE(ModuleManager::contains<TestModule>(DEFAULT_MODULE_NAME));
  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_SOME(module);

  // The TestModuleImpl module's implementation of foo() returns
  // the sum of the passed arguments, whereas bar() returns the
  // product. baz() returns '-1' if "sum" is not specified as the
  // "operation" in the command line parameters.
  EXPECT_EQ(1089, module.get()->foo('A', 1024));
  EXPECT_EQ(5, module.get()->bar(0.5, 10.8));
  EXPECT_EQ(-1, module.get()->baz(5, 10));
}


// Test that we can load module manifests from modules-dir.
TEST_F(ModuleTest, ModulesDirTest)
{
  string modulesDir = path::join(os::getcwd(), "modules_dir");
  ASSERT_SOME(os::mkdir(modulesDir));

  // Create a JSON file for the example module.
  EXPECT_SOME(os::write(
      path::join(modulesDir, "default_module.json"),
      stringify(JSON::protobuf(defaultModules))));

  // Let's also create another JSON file for the example module.
  EXPECT_SOME(os::write(
      path::join(modulesDir, "dup_default_module.json"),
      stringify(JSON::protobuf(defaultModules))));

  // Create a JSON for the 'TestHook' module.
  Modules extraModules = getModules("testhook", "org_apache_mesos_TestHook");

  EXPECT_SOME(os::write(
      path::join(modulesDir, "extra_module.json"),
      stringify(JSON::protobuf(extraModules))));

  // Now load modules using the modules directory.
  EXPECT_SOME(ModuleManager::load(modulesDir));

  EXPECT_TRUE(ModuleManager::contains<TestModule>(DEFAULT_MODULE_NAME));
  EXPECT_TRUE(ModuleManager::contains<Hook>("org_apache_mesos_TestHook"));

  // Perform cleanup.
  EXPECT_SOME(os::rmdir(modulesDir));
}


// Test passing parameter without value.
TEST_F(ModuleTest, ParameterWithoutValue)
{
  Modules modules = getModules(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "operation",
      "");

  EXPECT_SOME(ModuleManager::load(modules));
  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_ERROR(module);
}


// Test passing parameter with invalid value.
TEST_F(ModuleTest, ParameterWithInvalidValue)
{
  Modules modules = getModules(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "operation",
      "X");

  EXPECT_SOME(ModuleManager::load(modules));
  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_ERROR(module);
}


// Test passing parameter without key.
TEST_F(ModuleTest, ParameterWithoutKey)
{
  Modules modules = getModules(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "",
      "sum");

  EXPECT_SOME(ModuleManager::load(modules));
  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_SOME(module);

  // Since there was no valid key, baz() should return -1.
  EXPECT_EQ(-1, module.get()->baz(5, 10));
}


// Test passing parameter with invalid key.
TEST_F(ModuleTest, ParameterWithInvalidKey)
{
  Modules modules = getModules(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "X",
      "sum");

  EXPECT_SOME(ModuleManager::load(modules));
  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_SOME(module);

  // Since there was no valid key, baz() should return -1.
  EXPECT_EQ(-1, module.get()->baz(5, 10));
}


// Test passing parameter with valid key and value.
TEST_F(ModuleTest, ValidParameters)
{
  Modules modules = getModules(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "operation",
      "sum");

  EXPECT_SOME(ModuleManager::load(modules));
  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_SOME(module);

  EXPECT_EQ(15, module.get()->baz(5, 10));
}


// Tests overriding of module parameters programatically.
TEST_F(ModuleTest, OverrideJson)
{
  Modules modules = getModules(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "operation",
      "sum");

  EXPECT_SOME(ModuleManager::load(modules));

  Parameters parameters;
  Parameter* parameter = parameters.add_parameter();
  parameter->set_key("foo");
  parameter->set_value("foovalue");

  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME, parameters);
  EXPECT_SOME(module);

  parameters = module.get()->parameters();

  EXPECT_EQ(1, parameters.parameter_size());
  EXPECT_EQ("foo", parameters.parameter(0).key());
  EXPECT_EQ("foovalue", parameters.parameter(0).value());
}


// Test Json parsing to generate Modules protobuf.
TEST_F(ModuleTest, JsonParseTest)
{
  Try<Modules> modules = getModulesFromJson(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "operation",
      "sum");
  EXPECT_SOME(modules);

  EXPECT_SOME(ModuleManager::load(modules.get()));
  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_SOME(module);

  EXPECT_EQ(15, module.get()->baz(5, 10));
}


// Test that unloading a module succeeds if it has not been unloaded
// already.  Unloading unknown modules should fail as well.
TEST_F(ModuleTest, ExampleModuleUnloadTest)
{
  EXPECT_SOME(ModuleManager::load(defaultModules));

  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_SOME(module);

  // Unloading the module should succeed the first time.
  EXPECT_SOME(ModuleManager::unload(DEFAULT_MODULE_NAME));

  // Unloading the same module a second time should fail.
  EXPECT_ERROR(ModuleManager::unload(DEFAULT_MODULE_NAME));

  // Unloading an unknown module should fail.
  EXPECT_ERROR(ModuleManager::unload("unknown"));
}


// Verify that loading a module of an invalid kind fails.
TEST_F(ModuleTest, InvalidModuleKind)
{
  moduleBase->kind = "NotTestModule";
  EXPECT_ERROR(ModuleManager::load(defaultModules));
}


// Verify that loading a module of different kind fails.
TEST_F(ModuleTest, ModuleKindMismatch)
{
  EXPECT_SOME(ModuleManager::load(defaultModules));

  EXPECT_TRUE(ModuleManager::contains<TestModule>(DEFAULT_MODULE_NAME));
  EXPECT_FALSE(ModuleManager::contains<Isolator>(DEFAULT_MODULE_NAME));

  module = ModuleManager::create<TestModule>(DEFAULT_MODULE_NAME);
  EXPECT_SOME(module);
  EXPECT_ERROR(ModuleManager::create<Isolator>(DEFAULT_MODULE_NAME));
}


// Test for correct author name, author email and library description.
TEST_F(ModuleTest, AuthorInfoTest)
{
  EXPECT_STREQ("Apache Mesos", moduleBase->authorName);
  EXPECT_STREQ("modules@mesos.apache.org", moduleBase->authorEmail);
  EXPECT_STREQ("This is a test module.", moduleBase->description);
}


// Test that a module library gets loaded when provided with a
// library name without any extension and without the "lib" prefix.
TEST_F(ModuleTest, LibraryNameWithoutExtension)
{
  Modules modules;
  Modules::Library* library = modules.add_libraries();
  library->set_name(DEFAULT_MODULE_LIBRARY_NAME);
  library->set_file(getModulePath(DEFAULT_MODULE_LIBRARY_NAME));
  Modules::Library::Module* module = library->add_modules();
  module->set_name(DEFAULT_MODULE_NAME);

  EXPECT_SOME(ModuleManager::load(modules));
}


// Test that module library loading fails when filename is empty.
TEST_F(ModuleTest, EmptyLibraryFilename)
{
  Modules modules = getModules(
      "",
      "org_apache_mesos_TestModule");
  EXPECT_ERROR(ModuleManager::load(modules));
}


// Test that module library loading fails when module name is empty.
TEST_F(ModuleTest, EmptyModuleName)
{
  Modules modules = getModules("examplemodule", "");
  EXPECT_ERROR(ModuleManager::load(modules));
}


// Test that module library loading fails when given an unknown path.
TEST_F(ModuleTest, UnknownLibraryTest)
{
  Modules modules = getModules(
      "unknown",
      "org_apache_mesos_TestModule");
  EXPECT_ERROR(ModuleManager::load(modules));
}


// Test that module loading fails when given an unknown module name on
// the commandline.
TEST_F(ModuleTest, UnknownModuleTest)
{
  Modules modules = getModules("examplemodule", "unknown");
  EXPECT_ERROR(ModuleManager::load(modules));
}


// Test that module instantiation fails when given an unknown module
// name.
TEST_F(ModuleTest, UnknownModuleInstantiationTest)
{
  EXPECT_SOME(ModuleManager::load(defaultModules));
  EXPECT_ERROR(ModuleManager::create<TestModule>("unknown"));
}


// Test that loading a non-module library fails.
TEST_F(ModuleTest, NonModuleLibrary)
{
  // Trying to load libmesos.so (libmesos.dylib on OS X) as a module
  // library should fail.
  Modules modules = getModules("mesos", DEFAULT_MODULE_NAME);
  EXPECT_ERROR(ModuleManager::load(modules));
}


// Test that loading the same module twice works.
TEST_F(ModuleTest, LoadSameModuleTwice)
{
  // First load the default modules.
  EXPECT_SOME(ModuleManager::load(defaultModules));

  // Try to load the same module once again.
  EXPECT_SOME(ModuleManager::load(defaultModules));
}


// Test that loading the same module twice with different parameters fails.
TEST_F(ModuleTest, DuplicateModulesWithDifferentParameters)
{
  // First load the default modules.
  EXPECT_SOME(ModuleManager::load(defaultModules));

  // Create a duplicate modules object with some parameters.
  Modules duplicateModules = getModules(
      DEFAULT_MODULE_LIBRARY_NAME,
      DEFAULT_MODULE_NAME,
      "operation",
      "X");

  EXPECT_ERROR(ModuleManager::load(duplicateModules));
}


// Test that loading a duplicate module fails.
TEST_F(ModuleTest, DuplicateModuleInDifferentLibraries)
{
  // First load the default modules.
  EXPECT_SOME(ModuleManager::load(defaultModules));

  // Create a duplicate modules object with different library name.
  // We use the full name for library (i.e., examplemodule-X.Y.Z) to simulate
  // the case of two libraries with the same module.
  string library =
    string(DEFAULT_MODULE_LIBRARY_NAME).append("-").append(MESOS_VERSION);

  // Create a duplicate modules object with some parameters.
  Modules duplicateModules = getModules(library, DEFAULT_MODULE_NAME);

  EXPECT_ERROR(ModuleManager::load(duplicateModules));
}


// Test that loading a module library with a different API version
// fails
TEST_F(ModuleTest, DifferentApiVersion)
{
  // Make the API version '0'.
  moduleBase->moduleApiVersion = "0";
  EXPECT_ERROR(ModuleManager::load(defaultModules));

  // Make the API version arbitrarily high.
  moduleBase->moduleApiVersion = "1000";
  EXPECT_ERROR(ModuleManager::load(defaultModules));

  // Make the API version some random string.
  moduleBase->moduleApiVersion = "ThisIsNotAnAPIVersion!";
  EXPECT_ERROR(ModuleManager::load(defaultModules));
}


// Test that loading a module library compiled with a newer Mesos
// fails.
TEST_F(ModuleTest, NewerModuleLibrary)
{
  // Make the library version arbitrarily high.
  moduleBase->mesosVersion = "100.1.0";
  EXPECT_ERROR(ModuleManager::load(defaultModules));
}


// Test that loading a module library compiled with a really old
// Mesos fails.
TEST_F(ModuleTest, OlderModuleLibrary)
{
  // Make the library version arbitrarily low.
  moduleBase->mesosVersion = "0.1.0";
  EXPECT_ERROR(ModuleManager::load(defaultModules));
}

} // namespace tests {
} // namespace internal {
} // namespace mesos {