Improving processing of command line options.

Drafting implementation of command line options --initial and --reload (issues #230 and #231)
Removing command line option --admin-pathdb
Cleaning ProxySQL_GlobalVariables::process_opts_pre() and ProxySQL_GlobalVariables::process_opts_post()
Standard_ProxySQL_Admin::init() now opens file GloVars.admindb instead of "proxysql.db"
Improving command line processing in main()
ProxySQL_ConfigFile::OpenFile() exits in case of parsing error

Adding docs file on command line options

.gitignore

@@ -49,6 +49,8 @@ core
 
 #config
 proxysql.cnf*
+proxysql.cfg*
+proxysql.db*
 
 jeprof*heap
 perf.data*

doc/internal/command_line_options.txt

@@ -0,0 +1,19 @@
+Command Line Options
+
+Configuration of proxysql is performed through the processing of a config file, or a database file, or a combination of both.
+
+Config file is a read only file that proxysql does not modify.
+Database file is a read write file that proxysql can modify.
+The path of the config file can be passed to proxysql through the --config option.
+The path to the database file cannot be passed to proxysql directly, instead it is possible to pass its directory (called datadir) through the --datadir option.
+The database file is named proxysql.db inside the datadir.
+Both config file and datadir have default values if not specified in the command line.
+
+If a datadir is not provided in the command line, the config file is read to parse a possible datadir.
+
+If a database file is present in the datadir, its configuration is used by proxysql.
+
+If the option --initial is present, the database file is deleted.
+If a database file does not exist (or deleted because of --initial), the config file is parsed and a new database file is created based on its content.
+
+If the option --reload is specified, the config file is parsed and an attempt to merge its content with the database file is performed.

include/proxysql_glovars.hpp

@@ -15,15 +15,20 @@ class ProxySQL_GlobalVariables {
 	ez::ezOptionParser *opt;
 	//ezOptionParser *opt;
 	ProxySQL_ConfigFile *confFile;
+	bool configfile_open;
 	char *__cmd_proxysql_config_file;
 	char *__cmd_proxysql_datadir;
-	char *__cmd_proxysql_admin_pathdb;
+	//char *__cmd_proxysql_admin_pathdb;
 //	bool __cmd_proxysql_print_version=false;
 	int __cmd_proxysql_nostart;
 	int __cmd_proxysql_foreground;
 	int __cmd_proxysql_gdbg;
+	bool __cmd_proxysql_initial;
+	bool __cmd_proxysql_reload;
 	char *__cmd_proxysql_admin_socket;
 	char *config_file;
+	char *datadir;
+	char *admindb;
 	struct  {
 		bool gdbg;
 		bool nostart;

lib/ProxySQL_GloVars.cpp

@@ -30,7 +30,14 @@ ProxySQL_GlobalVariables::ProxySQL_GlobalVariables() {
 	confFile=NULL;
 	__cmd_proxysql_config_file=NULL;
 	__cmd_proxysql_datadir=NULL;
-	__cmd_proxysql_admin_pathdb=NULL;
+//	__cmd_proxysql_admin_pathdb=NULL;
+
+	config_file=NULL;
+	datadir=NULL;
+	configfile_open=false;
+
+	__cmd_proxysql_initial=false;
+	__cmd_proxysql_reload=false;
 
 	global.gdbg=false;
 	global.nostart=false;
@@ -68,7 +75,9 @@ opt.add(
 	opt->add((const char *)"~/proxysql.cnf",0,1,0,(const char *)"Configuraton file",(const char *)"-c",(const char *)"--config");
 	opt->add((const char *)"",0,1,0,(const char *)"Disable custom memory allocator",(const char *)"-m",(const char *)"--no-memory");
 	opt->add((const char *)"",0,1,0,(const char *)"Datadir",(const char *)"-D",(const char *)"--datadir");
-	opt->add((const char *)"",0,1,0,(const char *)"Configuration DB path",(const char *)"-a",(const char *)"--admin-pathdb");
+	opt->add((const char *)"",0,1,0,(const char *)"Rename/empty database file",(const char *)"--initial");
+	opt->add((const char *)"",0,1,0,(const char *)"Merge config file into database file",(const char *)"--reload");
+//	opt->add((const char *)"",0,1,0,(const char *)"Configuration DB path",(const char *)"-a",(const char *)"--admin-pathdb");
 	opt->add((const char *)"",0,1,0,(const char *)"Administration Unix Socket",(const char *)"-S",(const char *)"--admin-socket");
 //	opt.add("",0,0,0,"","-d","--debug");
 //	opt.add("",0,0,0,"","-d","--debug");
@@ -122,6 +131,24 @@ void ProxySQL_GlobalVariables::process_opts_pre() {
 		global.use_proxysql_mem=true;
 	}
 
+	if (opt->isSet("--initial")) {
+		__cmd_proxysql_initial=true;
+	}
+
+	if (opt->isSet("--reload")) {
+		__cmd_proxysql_reload=true;
+	}
+
+	
+	config_file=GloVars.__cmd_proxysql_config_file;
+
+	if (config_file==NULL) {
+		config_file=(char *)"proxysql.cnf";
+		//if (!g_file_test(config_file,(GFileTest)(G_FILE_TEST_EXISTS|G_FILE_TEST_IS_REGULAR))) {
+		if (Proxy_file_regular(config_file)==false) {
+			config_file=(char *)"/etc/proxysql.cnf";
+		}
+	}
 #ifdef DEBUG
 	init_debug_struct();
 #endif
@@ -139,7 +166,7 @@ void ProxySQL_GlobalVariables::process_opts_post() {
 	if (opt->isSet("-f")) {
 		global.foreground=true;
 	}
-
+/*
 	if (opt->isSet("-D")) {
 		std::string datadir;
 		opt->get("-D")->getString(datadir);
@@ -153,7 +180,7 @@ void ProxySQL_GlobalVariables::process_opts_post() {
 		if (GloVars.__cmd_proxysql_admin_pathdb) free(GloVars.__cmd_proxysql_admin_pathdb);
 		GloVars.__cmd_proxysql_admin_pathdb=strdup(admindb_path.c_str());
 	}
-
+*/
 	if (opt->isSet("-S")) {
 		std::string admin_socket;
 		opt->get("-S")->getString(admin_socket);
@@ -164,15 +191,6 @@ void ProxySQL_GlobalVariables::process_opts_post() {
 	proxy_debug(PROXY_DEBUG_GENERIC, 4, "processing opts\n");
 
   //gchar *config_file=*config_file_ptr;
-	config_file=GloVars.__cmd_proxysql_config_file;
-
-	if (config_file==NULL) {
-		config_file=(char *)"proxysql.cnf";
-		//if (!g_file_test(config_file,(GFileTest)(G_FILE_TEST_EXISTS|G_FILE_TEST_IS_REGULAR))) {
-		if (Proxy_file_regular(config_file)==false) {
-			config_file=(char *)"/etc/proxysql.cnf";
-		}
-	}
 
 //	rc=config_file_is_readable(config_file);
 //	if (rc==0) {
@@ -195,10 +213,10 @@ void ProxySQL_GlobalVariables::process_opts_post() {
 		free(glovars.proxy_datadir);
 		glovars.proxy_datadir=strdup(GloVars.__cmd_proxysql_datadir);
 	}
-	if (GloVars.__cmd_proxysql_admin_pathdb) {
-		free(glovars.proxy_admin_pathdb);
-		glovars.proxy_admin_pathdb=strdup(GloVars.__cmd_proxysql_admin_pathdb);
-	}
+//	if (GloVars.__cmd_proxysql_admin_pathdb) {
+//		free(glovars.proxy_admin_pathdb);
+//		glovars.proxy_admin_pathdb=strdup(GloVars.__cmd_proxysql_admin_pathdb);
+//	}
 	if (GloVars.__cmd_proxysql_admin_socket) {
 		free(glovars.proxy_admin_socket);
 		glovars.proxy_admin_socket=strdup(GloVars.__cmd_proxysql_admin_socket);

lib/Standard_ProxySQL_Admin.cpp

@@ -1420,7 +1420,7 @@ bool Standard_ProxySQL_Admin::init() {
 	statsdb=new SQLite3DB();
 	statsdb->open((char *)"file:mem_statsdb?mode=memory&cache=shared", SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_FULLMUTEX);
 	configdb=new SQLite3DB();
-	configdb->open((char *)"proxysql.db", SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_FULLMUTEX);
+	configdb->open((char *)GloVars.admindb, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_FULLMUTEX);
 
 
 	tables_defs_admin=new std::vector<table_def_t *>;

lib/configfile.cpp

@@ -63,6 +63,7 @@ bool ProxySQL_ConfigFile::OpenFile(const char *__filename) {
 	{
 		std::cerr << "Parse error at " << pex.getFile() << ":" << pex.getLine()
               << " - " << pex.getError() << std::endl;
+			exit(EXIT_FAILURE);
 		return false;
 	}
 	return true;

src/main.cpp

@@ -240,8 +240,56 @@ int main(int argc, const char * argv[]) {
 	GloVars.parse(argc,argv);
 
 	GloVars.process_opts_pre();
+
+	// alwasy try to open a config file
+	if (GloVars.confFile->OpenFile(GloVars.config_file) == true) {
+		GloVars.configfile_open=true;
+	}
+
+	if (GloVars.__cmd_proxysql_datadir==NULL) {
+		// datadir was not specified , try to read config file
+		if (GloVars.configfile_open==true) {
+			const Setting& root = GloVars.confFile->cfg.getRoot(); 
+			if (root.exists("datadir")==true) {
+				// reading datadir from config file
+				std::string datadir;
+				bool rc;
+				rc=root.lookupValue("datadir", datadir);
+				if (rc==true) {
+					GloVars.datadir=strdup(datadir.c_str());
+				} else {
+					GloVars.datadir=(char *)"/var/run/proxysql";
+				}
+			} else {
+			// datadir was not specified in config file
+			GloVars.datadir=(char *)"/var/run/proxysql";
+			}
+		} else {
+			// config file not readable
+			GloVars.datadir=(char *)"/var/run/proxysql";
+			std::cerr << "[Warning]: Cannot open config file " << GloVars.config_file << ". Using default datadir " << GloVars.datadir << endl;
+		}
+	} else {
+		GloVars.datadir=GloVars.__cmd_proxysql_datadir;
+	}
+
+	GloVars.admindb=(char *)malloc(strlen(GloVars.datadir)+strlen((char *)"proxysql.db")+2);
+	sprintf(GloVars.admindb,"%s/%s",GloVars.datadir, (char *)"proxysql.db");
+
+	if (GloVars.__cmd_proxysql_initial==true) {
+		std::cerr << "Renaming database file " << GloVars.admindb << endl;
+		char *newpath=(char *)malloc(strlen(GloVars.admindb)+8);
+		sprintf(newpath,"%s.bak",GloVars.admindb);
+		rename(GloVars.admindb,newpath);	// FIXME: should we check return value, or ignore whatever it successed or not?
+	}
+
+	GloVars.confFile->ReadGlobals();
+
+
+
 	GloVars.process_opts_post();
 
+/*
 	//if (GloVars.confFile->OpenFile("proxysql.cnf2") == true) {
 	if (GloVars.confFile->OpenFile(GloVars.config_file) == true) {
 		// open config file
@@ -249,11 +297,11 @@ int main(int argc, const char * argv[]) {
 		std::cerr << "[Warning]: Cannot open config file " << GloVars.config_file << endl;
 		//exit(EXIT_FAILURE);
 	}
-	GloVars.confFile->ReadGlobals();
+*/
 
 
 
-	bool rc;
+	//bool rc;
 
 	dlerror();
 	char* dlsym_error = NULL;

src/proxysql.cfg

@@ -5,6 +5,9 @@
 # Grammar is also copied at the end of this file
 
 
+
+datadir="/tmp"
+
 # defines all the MySQL servers
 mysql_servers =
 (
@@ -26,7 +29,7 @@ mysql_servers =
 		port=3306
 		hostgroup=0
 	},
-	{ address="127.0.0.1" , port=3306 , hostgroup=1 }
+	{ address="127.0.0.1" , port=3306 , hostgroup=1 },
 	{ address="127.0.0.2" , port=3306 , hostgroup=1 },
 	{ address="127.0.0.3" , port=3306 , hostgroup=1 },
 	{ address="127.0.0.4" , port=3306 , hostgroup=1 },
@@ -49,8 +52,8 @@ mysql_users:
 		default_hostgroup = 0
 #		active = 1
 	},
-	{ username = "user1" , password = "password" , default_hostgroup = 0 , active = 0 },
-)
+	{ username = "user1" , password = "password" , default_hostgroup = 0 , active = 0 }
+,)
 
 
 # http://www.hyperrealm.com/libconfig/libconfig_manual.html#Configuration-File-Grammar