Added a Boost.Log example cpp-netlib#14

Author: leisinmr

libs/network/example/http/hello_world_server_log.cpp

@@ -0,0 +1,117 @@
+// Copyright 2009 (c) Tarro, Inc.
+// Copyright 2009 (c) Dean Michael Berris <[email protected]>
+// Copyright 2011 (c) Matt Leisinger <[email protected]>
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+
+//[ hello_world_server_main
+/*`
+  This is a part of the 'Hello World' example. It's used to
+  demonstrate how easy it is to set up an HTTP server.  All we do in
+  this example is create a request handler and run the server. This
+  version of the server simply adds logging
+ */
+#include <iostream>
+
+#include <boost/network/protocol/http/server.hpp>
+
+#include <boost/log/common.hpp>
+#include <boost/log/formatters.hpp>
+#include <boost/log/filters.hpp>
+
+#include <boost/log/utility/init/to_file.hpp>
+#include <boost/log/utility/init/to_console.hpp>
+#include <boost/log/utility/init/common_attributes.hpp>
+
+#include <boost/log/attributes.hpp>
+#include <boost/log/attributes/timer.hpp>
+
+namespace http = boost::network::http;
+namespace logging = boost::log;
+namespace fmt = boost::log::formatters;
+namespace flt = boost::log::filters;
+namespace sinks = boost::log::sinks;
+namespace attrs = boost::log::attributes;
+namespace src = boost::log::sources;
+namespace keywords = boost::log::keywords;
+
+/*<< Defines the server. >>*/
+struct hello_world;
+typedef http::server<hello_world> server;
+
+/*<< Defines the request handler.  It's a class that defines two
+     functions, `operator()` and `log()` >>*/
+struct hello_world {
+    /*<< This is the function that handles the incoming request. >>*/
+    void operator() (server::request const &request,
+                     server::response &response) {
+        server::string_type ip = source(request);
+        std::ostringstream data;
+        data << "Hello, " << ip << "!";
+        response = server::response::stock_reply(
+            server::response::ok, data.str());
+    }
+    /*<< Using Boost.Log we'll simply log the number of errors >>*/
+    void log(const char *error) {
+        BOOST_LOG(lg) << "Error occured (" << error << "). Total number of errors reported is " << ++numErrors; 
+    }
+
+    /*<< Catch all for any other errors >>*/
+    void log(...) {
+        BOOST_LOG(lg) << "Unknown error occured. Total number of error reported is " << ++numErrors; 
+    }
+    private:
+        src::logger_mt lg;
+        uint32_t numErrors;
+        
+};
+
+/*<< Sets up two logger sinks, one to the console and the other to a file >>*/
+void init_logging()
+{
+    /*<< Setup the console logger >>*/
+    logging::init_log_to_console(std::clog, keywords::format = "%TimeStamp%: %_%");
+
+    /*<< Setup the file logger >>*/
+    logging::init_log_to_file
+    (
+        "hello_world_server.log",
+        keywords::format = fmt::format("[%1%] %2%")
+            % fmt::date_time("TimeStamp", std::nothrow)
+            % fmt::message(),
+        keywords::auto_flush = true
+    );
+
+    logging::add_common_attributes();
+}
+
+int main(int argc, char * argv[]) {
+    
+    if (argc != 3) {
+        std::cerr << "Usage: " << argv[0] << " address port" << std::endl;
+        return 1;
+    }
+
+    init_logging();
+    src::logger_mt lg;    
+
+    try {
+        /*<< Creates the request handler. >>*/
+        hello_world handler;
+        /*<< Creates the server. >>*/
+        server server_(argv[1], argv[2], handler);
+        /*<< Write to the log source >>*/
+        BOOST_LOG(lg) << "Starting HTTP Hello World Server...";
+        /*<< Runs the server. >>*/
+        server_.run();
+    }
+    catch (std::exception &e) {
+        std::cerr << e.what() << std::endl;
+        return 1;
+    }
+    
+    return 0;
+}
+//]