feat: add a logging interface, dependency injectable loggers (#233)

* feat(loggers): add a new generic dependency-injectable logger class

Signed-off-by: Max SCHMELLER <[email protected]>

* feat(loggers): add a console logger implementation

Signed-off-by: Max SCHMELLER <[email protected]>

* feat(loggers): add an rclcpp logger implementation

Signed-off-by: Max SCHMELLER <[email protected]>

* chore(logger): remove useless rule-of-five boilerplate

Signed-off-by: Max SCHMELLER <[email protected]>

---------

Signed-off-by: Max SCHMELLER <[email protected]>

nebula_common/include/nebula_common/loggers/console_logger.hpp

@@ -0,0 +1,55 @@
+// Copyright 2024 TIER IV, Inc.
+//
+// Licensed 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.
+
+#pragma once
+
+#include "nebula_common/loggers/logger.hpp"
+
+#include <cstdio>
+#include <iostream>
+#include <memory>
+#include <ostream>
+#include <string>
+#include <utility>
+
+namespace nebula::drivers::loggers
+{
+
+class ConsoleLogger : public Logger
+{
+public:
+  explicit ConsoleLogger(std::string name) : name_(std::move(name)) {}
+
+  void debug(const std::string & message) override { print_tagged(std::cout, "DEBUG", message); }
+  void info(const std::string & message) override { print_tagged(std::cout, "INFO", message); }
+  void warn(const std::string & message) override { print_tagged(std::cerr, "WARN", message); }
+  void error(const std::string & message) override { print_tagged(std::cerr, "ERROR", message); }
+
+  std::shared_ptr<Logger> child(const std::string & name) override
+  {
+    return std::make_shared<ConsoleLogger>(name_ + "." + name);
+  }
+
+private:
+  std::string name_;
+
+  void print_tagged(std::ostream & os, const std::string & severity, const std::string & message)
+  {
+    // In multithreaded logging, building the string first (... + ...) and then shifting to the
+    // stream will ensure that no other logger outputs between string fragments
+    os << ("[" + name_ + "][" + severity + "] " + message) << std::endl;
+  }
+};
+
+}  // namespace nebula::drivers::loggers

nebula_common/include/nebula_common/loggers/logger.hpp

@@ -0,0 +1,44 @@
+// Copyright 2024 TIER IV, Inc.
+//
+// Licensed 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.
+
+#pragma once
+
+#include <memory>
+#include <sstream>
+#include <string>
+
+#define NEBULA_LOG_STREAM(log_func, stream_args) \
+  {                                              \
+    std::stringstream ss{};                      \
+    ss << stream_args;                           \
+    log_func(ss.str());                          \
+  }
+
+namespace nebula::drivers::loggers
+{
+
+class Logger
+{
+public:
+  virtual ~Logger() = default;
+
+  virtual void debug(const std::string & message) = 0;
+  virtual void info(const std::string & message) = 0;
+  virtual void warn(const std::string & message) = 0;
+  virtual void error(const std::string & message) = 0;
+
+  virtual std::shared_ptr<Logger> child(const std::string & name) = 0;
+};
+
+}  // namespace nebula::drivers::loggers

nebula_ros/include/nebula_ros/common/rclcpp_logger.hpp

@@ -0,0 +1,59 @@
+// Copyright 2024 TIER IV, Inc.
+//
+// Licensed 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.
+
+#pragma once
+
+#include <nebula_common/loggers/logger.hpp>
+#include <rclcpp/logger.hpp>
+#include <rclcpp/logging.hpp>
+
+#include <memory>
+#include <string>
+
+namespace nebula::drivers::loggers
+{
+
+class RclcppLogger : public Logger
+{
+public:
+  explicit RclcppLogger(const std::string & name) : underlying_logger_(rclcpp::get_logger(name)) {}
+  explicit RclcppLogger(const rclcpp::Logger & underlying) : underlying_logger_(underlying) {}
+
+  void debug(const std::string & message) override
+  {
+    RCLCPP_DEBUG_STREAM(underlying_logger_, message);
+  }
+  void info(const std::string & message) override
+  {
+    RCLCPP_INFO_STREAM(underlying_logger_, message);
+  }
+  void warn(const std::string & message) override
+  {
+    RCLCPP_WARN_STREAM(underlying_logger_, message);
+  }
+  void error(const std::string & message) override
+  {
+    RCLCPP_ERROR_STREAM(underlying_logger_, message);
+  }
+
+  std::shared_ptr<Logger> child(const std::string & name) override
+  {
+    return std::make_shared<RclcppLogger>(underlying_logger_.get_child(name));
+  }
+
+private:
+  rclcpp::Logger underlying_logger_;
+};
+
+}  // namespace nebula::drivers::loggers