Merge pull request #191 from OSVR/ansi-color-sink-decorator

ANSI color sink decorator

CMakeLists.txt

@@ -6,6 +6,9 @@
 cmake_minimum_required(VERSION 3.0)
 project(spdlog VERSION 1.0.0)
 
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
 add_library(spdlog INTERFACE)
 
 option(SPDLOG_BUILD_EXAMPLES "Build examples" OFF)

example/example.cpp

@@ -5,9 +5,12 @@
 //
 // spdlog usage example
 //
+#include "spdlog/spdlog.h"
+#include "spdlog/sinks/ansicolor_sink.h"
+
 #include <cstdlib> // EXIT_FAILURE
 #include <iostream>
-#include "spdlog/spdlog.h"
+#include <memory>
 
 int main(int, char*[])
 {
@@ -85,6 +88,27 @@ int main(int, char*[])
         syslog_logger->warn("This is warning that will end up in syslog. This is Linux only!");
 #endif
 
+        //
+        // ANSI color logging (OS X and Linux. Windows only if ansi.sys is loaded.)
+        //
+
+        // Create a sink to add colors to.
+        auto console_out = spdlog::sinks::stderr_sink_st::instance();
+        auto color_sink = std::make_shared<spd::sinks::ansicolor_sink>(console_out);  // wraps around another sink
+        auto color_logger = spd::details::registry::instance().create("Color", color_sink);
+        color_logger->set_level(spd::level::trace);
+        color_sink->setColor(spd::level::info, color_sink->bold + color_sink->green);
+        color_logger->info("Testing color logger...");
+        color_logger->trace("Trace");
+        color_logger->debug("Debug");
+        color_logger->info("Info");
+        color_logger->notice("Notice");
+        color_logger->warn("Warning");
+        color_logger->error("Error");
+        color_logger->critical("Critical");
+        color_logger->alert("Alert");
+        color_logger->emerg("Emergency");
+
         //
         //Release and close all loggers
         //

include/spdlog/sinks/ansicolor_sink.h

@@ -0,0 +1,134 @@
+//
+// Copyright(c) 2016 Kevin M. Godby.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/common.h>
+
+#include <string>
+#include <map>
+
+namespace spdlog {
+namespace sinks {
+
+/**
+ * @brief The ansi_color_sink is a decorator around another sink and prefixes
+ * the output with an ANSI escape sequence color code depending on the severity
+ * of the message.
+ */
+class ansicolor_sink : public sink {
+public:
+    ansicolor_sink(sink_ptr sink);
+    virtual ~ansicolor_sink();
+
+    ansicolor_sink(const ansicolor_sink& other);
+    ansicolor_sink& operator=(const ansicolor_sink& other);
+
+    virtual void log(const details::log_msg& msg) override;
+    virtual void flush() override;
+
+    void setColor(level::level_enum level, const std::string& color);
+
+    /// \name Formatting codes
+    //@{
+    const std::string reset      = "\033[00m";
+    const std::string bold       = "\033[1m";
+    const std::string dark       = "\033[2m";
+    const std::string underline  = "\033[4m";
+    const std::string blink      = "\033[5m";
+    const std::string reverse    = "\033[7m";
+    const std::string concealed  = "\033[8m";
+    //@}
+
+    /// \name Foreground colors
+    //@{
+    const std::string grey       = "\033[30m";
+    const std::string red        = "\033[31m";
+    const std::string green      = "\033[32m";
+    const std::string yellow     = "\033[33m";
+    const std::string blue       = "\033[34m";
+    const std::string magenta    = "\033[35m";
+    const std::string cyan       = "\033[36m";
+    const std::string white      = "\033[37m";
+    //@}
+
+    /// \name Background colors
+    //@{
+    const std::string on_grey    = "\033[40m";
+    const std::string on_red     = "\033[41m";
+    const std::string on_green   = "\033[42m";
+    const std::string on_yellow  = "\033[43m";
+    const std::string on_blue    = "\033[44m";
+    const std::string on_magenta = "\033[45m";
+    const std::string on_cyan    = "\033[46m";
+    const std::string on_white   = "\033[47m";
+    //@}
+
+
+protected:
+    sink_ptr sink_;
+    std::map<level::level_enum, std::string> colors_;
+};
+
+inline ansicolor_sink::ansicolor_sink(sink_ptr sink) : sink_(sink)
+{
+    colors_[level::trace]    = white;
+    colors_[level::debug]    = white;
+    colors_[level::info]     = white;
+    colors_[level::notice]   = bold + white;
+    colors_[level::warn]     = bold + yellow;
+    colors_[level::err]      = red;
+    colors_[level::critical] = bold + red;
+    colors_[level::alert]    = bold + white + on_red;
+    colors_[level::emerg]    = bold + yellow + on_red;
+    colors_[level::off]      = reset;
+}
+
+inline ansicolor_sink::~ansicolor_sink()
+{
+    flush();
+}
+
+inline ansicolor_sink::ansicolor_sink(const ansicolor_sink& other) : sink_(other.sink_), colors_(other.colors_)
+{
+    // do nothing
+}
+
+
+inline ansicolor_sink& ansicolor_sink::operator=(const ansicolor_sink& other)
+{
+    if (this == &other)
+        return *this;
+
+    sink_ = other.sink_;
+    colors_ = other.colors_;
+    return *this;
+}
+
+inline void ansicolor_sink::log(const details::log_msg& msg)
+{
+    // Wrap the originally formatted message in color codes
+    const std::string prefix = colors_[msg.level];
+    const std::string s = msg.formatted.str();
+    const std::string suffix = reset;
+    details::log_msg m;
+    m.formatted.write(prefix + s + suffix);
+    sink_->log(m);
+}
+
+inline void ansicolor_sink::flush()
+{
+    sink_->flush();
+}
+
+inline void ansicolor_sink::setColor(level::level_enum level, const std::string& color)
+{
+    colors_[level] = color;
+}
+
+} // namespace sinks
+} // namespace spdlog
+