feat(SQLChannel): add times property to select UTC or local timestamps (#5399)

* feat(SQLChannel): add times property to select UTC or local timestamps #4925

* fix(SQLChannel): initialize _flush to DEFAULT_FLUSH_SECONDS #5400

Author: matejk

Data/include/Poco/Data/SQLChannel.h

@@ -192,7 +192,10 @@ class Data_API SQLChannel: public Poco::Channel, Poco::Runnable
 		///                  during an extened period of inactivity. This setting ensures that
 		///                  unlogged entries are flushed in such circumstances, even when the
 		///                  minimum batch size was not reached.
-		///                  Zero value means no flushing.
+		///                  Zero value means no flushing. Defaults to 10 seconds.
+		///
+		///     * times      Whether timestamps in SQL statements written to the file
+		///                  are in UTC ("UTC", default) or local time ("local").
 
 	std::string getProperty(const std::string& name) const override;
 		/// Returns the value of the property with the given name.
@@ -226,6 +229,7 @@ class Data_API SQLChannel: public Poco::Channel, Poco::Runnable
 	static const std::string PROP_DIRECTORY;
 	static const std::string PROP_FILE;
 	static const std::string PROP_FLUSH;
+	static const std::string PROP_TIMES;
 
 protected:
 	~SQLChannel() override;
@@ -280,6 +284,10 @@ class Data_API SQLChannel: public Poco::Channel, Poco::Runnable
 		/// Returns true if there are unflushed log entries
 		/// and the flush timer has expired.
 
+	std::string formatTimestamp(const DateTime& dt) const;
+		/// Returns the timestamp formatted in UTC or local time,
+		/// depending on the "times" property.
+
 	mutable Poco::FastMutex _mutex;
 
 	std::string       _connector;
@@ -296,6 +304,7 @@ class Data_API SQLChannel: public Poco::Channel, Poco::Runnable
 	std::atomic<bool> _bulk;
 	std::atomic<bool> _throw;
 	std::atomic<int>  _flush;
+	std::atomic<bool> _localTime;
 
 	// members for log entry cache
 	std::deque<std::string>      _source;

Data/src/SQLChannel.cpp

@@ -50,6 +50,7 @@ const std::string SQLChannel::PROP_THROW("throw");
 const std::string SQLChannel::PROP_DIRECTORY("directory");
 const std::string SQLChannel::PROP_FILE("file");
 const std::string SQLChannel::PROP_FLUSH("flush");
+const std::string SQLChannel::PROP_TIMES("times");
 
 
 const std::string SQLChannel::SQL_INSERT_STMT = "INSERT INTO %s " \
@@ -66,6 +67,8 @@ SQLChannel::SQLChannel():
 	_maxSQL(DEFAULT_MAX_SQL_SIZE),
 	_bulk(true),
 	_throw(false),
+	_flush(DEFAULT_FLUSH_SECONDS),
+	_localTime(false),
 	_pid(),
 	_tid(),
 	_priority(),
@@ -98,6 +101,8 @@ SQLChannel::SQLChannel(const std::string& connector,
 	_maxSQL(maxSQL),
 	_bulk(false),
 	_throw(false),
+	_flush(DEFAULT_FLUSH_SECONDS),
+	_localTime(false),
 	_pid(),
 	_tid(),
 	_priority(),
@@ -330,6 +335,14 @@ void SQLChannel::reconnect()
 }
 
 
+std::string SQLChannel::formatTimestamp(const DateTime& dt) const
+{
+	if (_localTime)
+		return DateTimeFormatter::format(LocalDateTime(dt), "%Y-%m-%d %H:%M:%S.%i");
+	return DateTimeFormatter::format(dt, "%Y-%m-%d %H:%M:%S.%i");
+}
+
+
 size_t SQLChannel::logToFile(bool flush)
 {
 	if (_source.empty()) return 0u;
@@ -386,7 +399,7 @@ size_t SQLChannel::logToFile(bool flush)
 		int idx = 0;
 		for (; it != end; ++idx)
 		{
-			std::string dt = DateTimeFormatter::format(_dateTime[idx], "%Y-%m-%d %H:%M:%S.%i");
+			std::string dt = formatTimestamp(_dateTime[idx]);
 			tmp.str("");
 			tmp << "('" << *it << "','" <<
 				names[idx] << "'," <<
@@ -660,6 +673,10 @@ void SQLChannel::setProperty(const std::string& name, const std::string& value)
 	{
 		_flush.store(NumberParser::parse(value));
 	}
+	else if (name == PROP_TIMES)
+	{
+		_localTime = (value == "local");
+	}
 	else
 	{
 		Channel::setProperty(name, value);
@@ -734,6 +751,10 @@ std::string SQLChannel::getProperty(const std::string& name) const
 	{
 		return std::to_string(_flush);
 	}
+	else if (name == PROP_TIMES)
+	{
+		return _localTime ? "local" : "UTC";
+	}
 	else
 	{
 		return Channel::getProperty(name);

Data/testsuite/src/DataTest.cpp

@@ -1584,12 +1584,19 @@ void DataTest::testSQLChannel()
 		}
 	}
 
+	assertEqual(int(SQLChannel::DEFAULT_FLUSH_SECONDS), NumberParser::parse(pChannel->getProperty("flush")));
+
 	constexpr int mcount{10};
 	constexpr int batch{3};
 	pChannel->setProperty("minBatch", std::to_string(batch));
 	constexpr int flush{1};
 	pChannel->setProperty("flush", std::to_string(flush));
 	assertEqual(flush, NumberParser::parse(pChannel->getProperty("flush")));
+	assertTrue(pChannel->getProperty("times") == "UTC");
+	pChannel->setProperty("times", "local");
+	assertTrue(pChannel->getProperty("times") == "local");
+	pChannel->setProperty("times", "UTC");
+	assertTrue(pChannel->getProperty("times") == "UTC");
 	for (int i = 0; i < mcount; i++)
 	{
 		Message msgInfA("InformationSource", Poco::format("%d Informational sync message", i), Message::PRIO_INFORMATION);