DecoupleLogger

[中文]

DecoupleLogger is a C++11 logging decoupling library with only one header file. He can decouple the reference to the logging library from the code, so you can more simply distill the original code and do the corresponding unit tests.

How to use

It is highly recommended to look at the example/helloworld.cpp code after reading README as it will help you understand using DecoupleLogger.

When you define a class, you can inherit the class from LoggerBase, and then use the callLog member function within the class to call the log.

class Table : public LoggerBase {
public:
  void testLog() { callLog(LogLevel::INFO, "this is the %s's log", "Table"); }
};

When you instantiate the Table class, you need to call setLoggerFunc to set the logging function for that class.

Table tb;
tb.setLoggerFunc([&](const LogLevel &log_level, const std::string &msg) {
    // You can reference the log library here or do some custom operations
    printf("%s\n", msg.c_str());
  });

Otherwise it will pop up when calling the log.

* WARN: LoggerBase class hasn't setLoggerFunc yet!

Feature Description

Logging functions can be delivered automatically

When we read the above example, we may worry whether it is too tedious to call setLoggerFunc manually when the classes have more nested relationships. Don't worry, setLoggerFunc of DecoupleLogger is able to distribute logging functions downwards. But you need to manually specify the member variables that also inherit from LoggerBase.

In example/helloworld.cpp, class ClassRoom contains two member variables tb and ch, both of which inherit from LoggerBase, so I called registLoggerSubClass in ClassRoom's constructor to register tb and ch.

ClassRoom() {
    registLoggerSubClass(&tb);
    registLoggerSubClass(&ch);
}

This way when using it we just need to call setLoggerFunc of ClassRoom to automatically set the same logging member functions for tb and ch.

Support for text format

callLog can accept fmt like printf and output the log using variable parameters. Note that you should keep an eye on the log length in your project and modify LOG_MAX_LENGTH as necessary to avoid the log being truncated by snprintf.