Try to switch the configurators to non-virtual interface template

src/Configurator.h

@@ -12,6 +12,12 @@
 
 #include <vector>
 #include <string>
+#include <map>
+
+#include <boost/foreach.hpp>
+#include <boost/algorithm/string.hpp>
+#include <boost/property_tree/ptree.hpp>
+#include <boost/property_tree/info_parser.hpp>
 
 typedef struct {
 	std::string mqttPrefix;
@@ -20,10 +26,15 @@ typedef struct {
 } pluginSettings_t;
 
 /**
- * Base class, which defines the interface for the configurators in the shared dynamic libraries.
- * This base class shall not be constructed on itw own.
+ * Non-virtual interface template for the configurators.
  */
+template <typename S>
 class Configurator {
+	//the template shall only be instantiated for the sensors corresponding to the configurator
+	static_assert(std::is_base_of<Sensor, S>::value, "S must derive from Sensor!");
+
+	typedef std::map<std::string, S> sensorMap_t;
+
 public:
 	Configurator() : _cacheInterval(900000) {}
 
@@ -35,47 +46,175 @@ public:
 
 	/**
 	 * Read in the given configuration
+	 *
 	 * @param	cfgPath Path to the config-file
-	 * @return	true on success, false otherwise
+	 *
+	 * @return	True on success, false otherwise
 	 */
-	virtual bool readConfig(std::string cfgPath) {
+	bool readConfig(std::string cfgPath) {
 		_cfgPath = cfgPath;
-		return true;
+
+		boost::property_tree::iptree cfg;
+		boost::property_tree::read_info(cfgPath, cfg);
+
+		//read global variables (if present overwrite those from global.conf)
+		BOOST_FOREACH(boost::property_tree::iptree::value_type &global, cfg.get_child("global")) {
+			if (boost::iequals(global.first, "mqttprefix")) {
+				_mqttPrefix = global.second.data();
+				if (_mqttPrefix[_mqttPrefix.length()-1] != '/') {
+					_mqttPrefix.append("/");
+				}
+				LOG(debug) << "  Using own MQTT-Prefix " << _mqttPrefix;
+			} else if (boost::iequals(global.first, "cacheInterval")) {
+				_cacheInterval = stoul(global.second.data());
+				LOG(debug) << "  Using own caching interval " << _cacheInterval << " [s]";
+				_cacheInterval *= 1000;
+			} else {
+				LOG(error) << "  Value \"" << global.first << "\" not recognized. Omitting...";
+			}
+		}
+
+		//read template sensors
+		BOOST_FOREACH(boost::property_tree::iptree::value_type &sens, cfg.get_child("templates")) {
+			if (boost::iequals(sens.first, "sensor")) {
+				LOG(debug) << "Template Sensor \"" << sens.second.data() << "\"";
+				if (!sens.second.empty()) {
+					S sensor(sens.second.data());
+					if(readSensor(sensor, sens.second)) {
+						_templateSensors.insert(sensorMap_t::value_type(sensor.getName(), sensor));
+					} else {
+						LOG(warning) << "Template sensor \"" << sens.second.data() << "\" has bad values! Ignoring...";
+					}
+				}
+			}
+		}
+
+		//read in plugin specific stuff (including actual sensors)
+		return derivedReadConfig(cfg);
 	}
 
 	/**
 	 * Clear internal storage and read in the configuration again.
+	 *
+	 * @return	True on success, false otherwise
 	 */
-	virtual bool reReadConfig() {
+	bool reReadConfig() {
 		for (auto s : _sensors) {
 			s->stopPolling();
 		}
+
+		derivedReReadConfig();
+
 		for (auto s : _sensors) {
 			delete s;
 		}
 		_sensors.clear();
-		return this->readConfig(_cfgPath);
+		_templateSensors.clear();
+
+		return readConfig(_cfgPath);
 	}
 
-	virtual void setGlobalSettings(const pluginSettings_t& pluginSettings) {
+	/**
+	 * Sets internal variables with the ones provided by pluginSettings.
+	 * This method should be called once after constructing a configurator
+	 * to provide him with the global default values.
+	 *
+	 * @param pluginSettings	Struct with global default settings for the plugins.
+	 */
+	void setGlobalSettings(const pluginSettings_t& pluginSettings) {
 		_mqttPrefix = pluginSettings.mqttPrefix;
 		_cacheInterval = pluginSettings.cacheInterval;
+
+		derivedSetGlobalSettings(pluginSettings);
 	}
 
+	/**
+	 * Get all sensors
+	 *
+	 * @return	Vector containing pointers to all sensors of this plugin
+	 */
 	std::vector<Sensor*>& getSensors() {
 		return _sensors;
 	}
 
 protected:
-	std::string _cfgPath;
-	std::string _mqttPrefix;
-	unsigned int _cacheInterval;
+	/**
+	 * Non-virtual interface method for class-internal use only.
+	 * Reads and sets the common base values of a sensor, then calls
+	 * the corresponding derived function.
+	 *
+	 * @param sensor	The sensor for which to set the values
+	 * @param config	A boost property (sub-)tree containing the sensor values
+	 *
+	 * @return	True on success, false otherwise
+	 */
+	bool readSensor(S& sensor, boost::property_tree::iptree& config) {
+		//read in base values
+		BOOST_FOREACH(boost::property_tree::iptree::value_type &val, config) {
+			if (boost::iequals(val.first, "interval")) {
+				sensor.setInterval(stoull(val.second.data()));
+			} else if (boost::iequals(val.first, "mqttsuffix")) {
+				sensor.setMqtt(sensor.getMqtt() + val.second.data());
+			} else if (boost::iequals(val.first, "minValues")) {
+				sensor.setMinValues(stoull(val.second.data()));
+			} else {
+				//do nothing. Derived function should read in other values
+			}
+		}
+		sensor.setCacheInterval(_cacheInterval);
+
+		LOG(debug) << "  MQTT     : " << sensor.getMqtt();
+		LOG(debug) << "  Interval : " << sensor.getInterval();
+		LOG(debug) << "  minValues: " << sensor.getMinValues();
+
+		return derivedReadSensor(sensor, config);
+	}
+
+	/**
+	 * Pure virtual interface method, responsible for reading the plugin-specific
+	 * configuration part.
+	 *
+	 * @param cfg	The (root) boost property tree from the plugins configuration file
+	 *
+	 * @return	True on success, false otherwise
+	 */
+	virtual bool derivedReadConfig(boost::property_tree::iptree& cfg) = 0;
+
+	/**
+	 * Pure virtual interface method, responsible for the plugin specific part if
+	 * re-reading the config.
+	 */
+	virtual void derivedReReadConfig() = 0;
+
+	/**
+	 * Pure virtual interface method, responsible for setting global values specifically
+	 * for its plugin.
+	 *
+	 * @param pluginSettings	The struct with global default plugin settings
+	 */
+	virtual void derivedSetGlobalSettings(const pluginSettings_t& pluginSettings) = 0;
+
+	/**
+	 * Pure virtual interface method, responsible for reading plugin-specific sensor
+	 * values.
+	 *
+	 * @param sensor	The sensor for which to set the values
+	 * @param config	A boost property (sub-)tree containing the sensor values
+	 *
+	 * @return	True on success, false otherwise
+	 */
+	virtual bool derivedReadSensor(S& sensor, boost::property_tree::iptree& config) = 0;
+
+	std::string 	_cfgPath;
+	std::string		_mqttPrefix;
+	unsigned int	_cacheInterval;
 	std::vector<Sensor*> _sensors;
+	sensorMap_t		_templateSensors;
 	boost::log::sources::severity_logger<boost::log::trivial::severity_level> lg;
 };
 
 //typedef for more readable usage of create()- and destroy()-methods, required for dynamic libraries
-typedef Configurator* create_t();
-typedef void destroy_t(Configurator*);
+typedef Configurator<Sensor>* create_t();
+typedef void destroy_t(Configurator<Sensor>*);
 
 #endif /* SRC_CONFIGURATOR_H_ */

src/PluginDefinitions.h

@@ -23,7 +23,7 @@
 typedef struct {
 	std::string id;
 	void*	DL;
-	Configurator* configurator;
+	Configurator<Sensor>* configurator;
 	create_t*  create;
 	destroy_t* destroy;
 } dl_t;

src/sensors/snmp/SNMPConfigurator.cpp

@@ -7,10 +7,6 @@
 
 #include "SNMPConfigurator.h"
 
-#include <boost/foreach.hpp>
-#include <boost/property_tree/info_parser.hpp>
-#include <boost/algorithm/string.hpp>
-
 SNMPConfigurator::SNMPConfigurator() {
 	/* Initialize SNMP library */
 	init_snmp("dcdbpusher_SNMPplugin");
@@ -18,45 +14,9 @@ SNMPConfigurator::SNMPConfigurator() {
 
 SNMPConfigurator::~SNMPConfigurator() {}
 
-bool SNMPConfigurator::readConfig(std::string cfgPath) {
-	Configurator::readConfig(cfgPath);
-	boost::property_tree::iptree cfg;
-	boost::property_tree::read_info(cfgPath, cfg);
-
+bool SNMPConfigurator::derivedReadConfig(boost::property_tree::iptree& cfg) {
 	std::string mqttPartConnection;
 
-	//read global variables (if present overwrite those from global.conf)
-	BOOST_FOREACH(boost::property_tree::iptree::value_type &global, cfg.get_child("global")) {
-		if (boost::iequals(global.first, "mqttprefix")) {
-			_mqttPrefix = global.second.data();
-			if (_mqttPrefix[_mqttPrefix.length()-1] != '/') {
-				_mqttPrefix.append("/");
-			}
-			LOG(debug) << "  Using own MQTT-Prefix " << _mqttPrefix;
-		} else if (boost::iequals(global.first, "cacheInterval")) {
-			_cacheInterval = stoul(global.second.data());
-			LOG(debug) << "  Using own caching interval " << _cacheInterval << " [s]";
-			_cacheInterval *= 1000;
-		} else {
-			LOG(error) << "  Value \"" << global.first << "\" not recognized. Omitting...";
-		}
-	}
-
-	//read template sensors
-	BOOST_FOREACH(boost::property_tree::iptree::value_type &sensor, cfg.get_child("templates")) {
-		if (boost::iequals(sensor.first, "sensor")) {
-			LOG(debug) << "Template Sensor \"" << sensor.second.data() << "\"";
-			if (!sensor.second.empty()) {
-				SNMPSensor snmpSensor(sensor.second.data());
-				if(readSensor(snmpSensor, sensor.second)) {
-					_templateSensors.insert(sensorMap_t::value_type(snmpSensor.getName(), snmpSensor));
-				} else {
-					LOG(warning) << "Template sensor \"" << sensor.second.data() << "\" has bad values! Ignoring...";
-				}
-			}
-		}
-	}
-
 	BOOST_FOREACH(boost::property_tree::iptree::value_type &connection, cfg.get_child("connections")) {
 		if (boost::iequals(connection.first, ("connection"))) {
 			LOG(debug) << "Connection " << connection.second.data();
@@ -186,27 +146,25 @@ bool SNMPConfigurator::readConfig(std::string cfgPath) {
 	return true;
 }
 
-bool SNMPConfigurator::readSensor(SNMPSensor& sensor, boost::property_tree::iptree& config) {
+void SNMPConfigurator::derivedReReadConfig() {
+	sleep(5);
+	_connections.clear();
+}
+
+bool SNMPConfigurator::derivedReadSensor(SNMPSensor& sensor, boost::property_tree::iptree& config) {
 	BOOST_FOREACH(boost::property_tree::iptree::value_type &val, config) {
 		if (boost::iequals(val.first, "interval")) {
-			sensor.setInterval(stoull(val.second.data()));
+			//avoid unnecessary "Value not recognized" messages
 		} else if (boost::iequals(val.first, "mqttsuffix")) {
-			sensor.setMqtt(sensor.getMqtt() + val.second.data());
 		} else if (boost::iequals(val.first, "minValues")) {
-			sensor.setMinValues(stoull(val.second.data()));
+		} else if (boost::iequals(val.first, "default")) {
 		} else if (boost::iequals(val.first, "OID")) {
 			sensor.setOID(sensor.getConnection()->getOIDPrefix() + "." + val.second.data());
-		} else if (boost::iequals(val.first, "default")) {
-			//avoid unnecessary "Value not recognized" message
 		} else {
 			LOG(warning) << "  Value \"" << val.first << "\" not recognized. Omitting...";
 		}
 	}
-	sensor.setCacheInterval(_cacheInterval);
 
-	LOG(debug) << "  MQTT     : " << sensor.getMqtt();
-	LOG(debug) << "  Interval : " << sensor.getInterval();
-	LOG(debug) << "  minValues: " << sensor.getMinValues();
 	LOG(debug) << "  OID      : " << sensor.getOIDString();
 	return true;
 }

src/sensors/snmp/SNMPConfigurator.h

@@ -13,49 +13,27 @@
 #include "SNMPSensor.h"
 #include "SNMPConnection.h"
 
-#include <string>
-#include <vector>
-#include <map>
 #include <list>
-#include <boost/property_tree/ptree.hpp>
 
-class SNMPConfigurator : public Configurator {
+class SNMPConfigurator : public Configurator<SNMPSensor> {
 
 	typedef std::list<SNMPConnection> connectionList_t;
-	typedef std::map<std::string, SNMPSensor> sensorMap_t;
 
 public:
 	SNMPConfigurator();
 	virtual ~SNMPConfigurator();
 
-	/**
-	 * Read in the configuration for snmp-connections and sensors.
-	 * @param cfgPath	Path + name of the config-file
-	 * @return		true on success, false otherwise
-	 */
-	bool readConfig(std::string cfgPath);
+protected:
+	bool derivedReadConfig(boost::property_tree::iptree& cfg) final;
 
-	//Overwrite from Configurator
-	bool reReadConfig() {
-		for (auto s : _sensors) {
-			s->stopPolling();
-		}
-		sleep(10);
-		_connections.clear();
-		_templateSensors.clear();
-		return Configurator::reReadConfig();
-	}
+	void derivedReReadConfig() final;
 
-private:
-	/**
-	 * Set the variables of sensor according to the values specified in config.
-	 * @param sensor	The sensor to be configured
-	 * @param config	A property(sub)tree containing the values
-	 */
-	bool readSensor(SNMPSensor& sensor, boost::property_tree::iptree& config);
+	void derivedSetGlobalSettings(const pluginSettings_t& pluginSettings) final {/*nothing to overwrite*/}
+
+	bool derivedReadSensor(SNMPSensor& sensor, boost::property_tree::iptree& config) final;
 
+private:
 	connectionList_t	_connections;
-	sensorMap_t			_templateSensors;
 };
 
 extern "C" Configurator* create() {