added config file class, but not very well encapsulated

grive/CMakeLists.txt

@@ -7,8 +7,12 @@ include_directories(
 
 add_definitions( -DVERSION="${GRIVE_VERSION}" )
 
+file (GLOB GRIVE_EXE_SRC
+    ${grive_SOURCE_DIR}/src/*.cc
+)
+
 add_executable( grive_executable
-	src/main.cc
+	${GRIVE_EXE_SRC}
 )
 
 target_link_libraries( grive_executable

grive/src/Config.cc

@@ -0,0 +1,70 @@
+/*
+	grive: an GPL program to sync a local directory with Google Drive
+	Copyright (C) 2012  Wan Wai Ho
+
+	This program is free software; you can redistribute it and/or
+	modify it under the terms of the GNU General Public License
+	as published by the Free Software Foundation version 2
+	of the License.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the Free Software
+	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#include "Config.hh"
+
+#include <fstream>
+#include <iterator>
+
+namespace gr {
+
+const std::string& Config::Filename()
+{
+	static const char *env_cfg = ::getenv( "GR_CONFIG" ) ;
+	static const std::string filename =
+		(env_cfg != 0) ? env_cfg : std::string( ::getenv( "HOME") ) + "/.grive" ;
+
+	return filename ;
+}
+
+Config::Config()
+{
+	std::ifstream ifile( Filename().c_str() ) ;
+	if ( ifile )
+	{
+		try
+		{
+			std::string cfg_str(
+				(std::istreambuf_iterator<char>( ifile )),
+				(std::istreambuf_iterator<char>()) ) ;
+			
+			m_cfg = Json::Parse( cfg_str ) ;
+		}
+		catch ( Exception& e )
+		{
+			throw Error()
+				<< File( Filename() )
+				<< expt::ErrMsg("Cannot open config file ")
+				<< expt::Nested(e) ;
+		}
+	}
+}
+
+void Config::Save( )
+{
+	std::ofstream ofile( Filename().c_str() ) ;
+	ofile << m_cfg ;
+}
+
+Json& Config::Get()
+{
+	return m_cfg ;
+}
+
+} // end of namespace

grive/src/Config.hh

@@ -0,0 +1,44 @@
+/*
+	grive: an GPL program to sync a local directory with Google Drive
+	Copyright (C) 2012  Wan Wai Ho
+
+	This program is free software; you can redistribute it and/or
+	modify it under the terms of the GNU General Public License
+	as published by the Free Software Foundation version 2
+	of the License.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the Free Software
+	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#pragma once
+
+#include "util/Exception.hh"
+#include "protocol/Json.hh"
+
+namespace gr {
+
+class Config
+{
+public :
+	struct Error : virtual Exception {} ;
+	typedef boost::error_info<struct FileTag, std::string>	File ;
+
+	static const std::string& Filename() ;
+
+	Config() ;
+	
+	Json& Get() ;
+	void Save() ;
+
+private :
+	Json m_cfg ;
+} ;
+	
+} // end of namespace

grive/src/main.cc

@@ -17,6 +17,8 @@
 	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
 
+#include "Config.hh"
+
 #include "drive/Drive.hh"
 
 #include "protocol/OAuth2.hh"
@@ -31,68 +33,17 @@
 
 #include <cassert>
 #include <cstdlib>
-#include <fstream>
 #include <iostream>
 #include <unistd.h>
-#include <iterator>
-
-#include <exception>
-#include <stdexcept>
 
 const std::string client_id		= "22314510474.apps.googleusercontent.com" ;
 const std::string client_secret	= "bl4ufi89h-9MkFlypcI7R785" ;
 
-namespace gr
-{
-	class ConfigError : public std::runtime_error
-	{
-	public :
-		ConfigError( const std::string& msg ) : runtime_error( msg )
-		{
-		}
-	} ;
-
-	const std::string& ConfigFilename()
-	{
-		static const char *env_cfg = ::getenv( "GR_CONFIG" ) ;
-		static const std::string filename =
-			(env_cfg != 0) ? env_cfg : std::string( ::getenv( "HOME") ) + "/.grive" ;
-
-		return filename ;
-	}
-
-	Json ReadConfig()
-	{
-		std::ifstream ifile( ConfigFilename().c_str() ) ;
-		if ( !ifile )
-			return Json() ;
-		
-		try
-		{
-			std::string cfg_str(
-				(std::istreambuf_iterator<char>( ifile )),
-				(std::istreambuf_iterator<char>()) ) ;
-			
-			return Json::Parse( cfg_str ) ;
-		}
-		catch ( std::runtime_error& e )
-		{
-			throw ConfigError( std::string("Cannot open config file ") + e.what() ) ;
-		}
-	}
-	
-	void SaveConfig( const Json& config )
-	{
-		std::ofstream ofile( ConfigFilename().c_str() ) ;
-		ofile << config ;
-	}
-}
-
 int main( int argc, char **argv )
 {
 	using namespace gr ;
 
-	Json config = ReadConfig() ;
+	Config config ;
 	
 	DefaultLog nofile_log ;
 	LogBase::Inst( &nofile_log ) ;
@@ -120,9 +71,9 @@ int main( int argc, char **argv )
 				token.Auth( code ) ;
 				
 				// save to config
-				config.Add( "refresh_token", Json( token.RefreshToken() ) ) ;
-				assert( config["refresh_token"].As<std::string>() == token.RefreshToken() ) ;
-				SaveConfig( config ) ;
+				config.Get().Add( "refresh_token", Json( token.RefreshToken() ) ) ;
+				assert( config.Get()["refresh_token"].Str() == token.RefreshToken() ) ;
+				config.Save( ) ;
 				
 				break ;
 			}
@@ -147,7 +98,7 @@ int main( int argc, char **argv )
 	std::string refresh_token ;
 	try
 	{
-		refresh_token = config["refresh_token"].As<std::string>() ;
+		refresh_token = config.Get()["refresh_token"].Str() ;
 	}
 	catch ( const std::runtime_error& error )
 	{

libgrive/src/util/Exception.hh

@@ -70,6 +70,9 @@ namespace expt
 
 	// generic error message
 	typedef boost::error_info<struct MsgTag, std::string>		ErrMsg ;
+	
+	// nested exception
+	typedef boost::error_info<struct ExceptionTag, Exception>	Nested ;
 }
 
 } // end of namespace