Merge branch 'poco-1.10.1' into devel

CHANGELOG

@@ -11,6 +11,8 @@ Release 1.10.1 (2020-02-10)
 - GH #2791: allow pre-allocation of the buffer in Poco::LogStreamBuf.
 - GH #2816: Modernise TLS configuration
 - GH #2818: Add getSpecifiedPort() method in Poco::URI.
+- MySQL: resetting the session when putting it back into a SessionPool is now optional
+  (and disabled by default) due to a bug in MySQL messing up the character encoding when doing so.
 
 
 Release 1.10.0 (2020-01-27)

Data/MySQL/include/Poco/Data/MySQL/SessionImpl.h

@@ -41,19 +41,30 @@ public:
 	static const std::string MYSQL_REPEATABLE_READ;
 	static const std::string MYSQL_SERIALIZABLE;
 
-	SessionImpl(const std::string& connectionString,
-		std::size_t loginTimeout = LOGIN_TIMEOUT_DEFAULT);
-		/// Creates the SessionImpl. Opens a connection to the database
+	SessionImpl(const std::string& connectionString, std::size_t loginTimeout = LOGIN_TIMEOUT_DEFAULT);
+		/// Creates the SessionImpl. Opens a connection to the database.
 		///
 		/// Connection string format:
 		///     <str> == <assignment> | <assignment> ';' <str>
 		///     <assignment> == <name> '=' <value>
-		///     <name> == 'host' | 'port' | 'user' | 'password' | 'db' } 'compress' | 'auto-reconnect'
+		///     <name> == 'host' | 'port' | 'user' | 'password' | 'db' | 'compress' | 'auto-reconnect' | 'reset'
 		///     <value> == [~;]*
 		///
-		/// for compress and auto-reconnect correct values are true/false
-		/// for port - numeric in decimal notation
+		/// The following settings are supported:
+		///   - host: MySQL server hostname or IP address (default: localhost)
+		///   - port: MySQL server port number (default: 3306)
+		///   - user: MySQL user name
+		///   - password: MySQL password
+		///   - compress: enable compression (true/false; default: false)
+		///   - auto-reconnect: enable automatic reconnect (true/false; default: false)
+		///   - secure-auth: use secure authentication (true/false; default: false)
+		///   - character-set: connection character set (default: utf8)
+		///   - reset: reset connection when returned to SessionPool by calling
+		///     mysql_reset_connection().
 		///
+		/// Warning: Due to a bug in MySQL, resetting the connection with mysql_reset_connection()
+		/// could change the character encoding used for the connection. Therefore the
+		/// reset option should be used with caution.
 
 	~SessionImpl();
 		/// Destroys the SessionImpl.
@@ -182,6 +193,7 @@ private:
 
 	std::string           _connector;
 	mutable SessionHandle _handle;
+	bool                  _reset;
 	bool                  _connected;
 	bool                  _inTransaction;
 	bool                  _failIfInnoReadOnly;

Data/MySQL/src/SessionImpl.cpp

@@ -48,6 +48,7 @@ SessionImpl::SessionImpl(const std::string& connectionString, std::size_t loginT
 	Poco::Data::AbstractSessionImpl<SessionImpl>(connectionString, loginTimeout),
 	_connector("MySQL"),
 	_handle(0),
+	_reset(false),
 	_connected(false),
 	_inTransaction(false),
 	_failIfInnoReadOnly(false),
@@ -90,6 +91,7 @@ void SessionImpl::open(const std::string& connect)
 	options["auto-reconnect"] = "";
 	options["secure-auth"] = "";
 	options["character-set"] = "utf8";
+	options["reset"] = "";
 
 	const std::string& connString = connectionString();
 	for (std::string::const_iterator start = connString.begin();;)
@@ -123,14 +125,14 @@ void SessionImpl::open(const std::string& connect)
 	else if (options["compress"] == "false")
 		;
 	else if (!options["compress"].empty())
-		throw MySQLException("create session: specify correct compress option (true or false) or skip it");
+		throw MySQLException("create session: specify correct compress option (true or false)");
 
 	if (options["auto-reconnect"] == "true")
 		_handle.options(MYSQL_OPT_RECONNECT, true);
 	else if (options["auto-reconnect"] == "false")
 		_handle.options(MYSQL_OPT_RECONNECT, false);
 	else if (!options["auto-reconnect"].empty())
-		throw MySQLException("create session: specify correct auto-reconnect option (true or false) or skip it");
+		throw MySQLException("create session: specify correct auto-reconnect option (true or false)");
 
 #ifdef MYSQL_SECURE_AUTH
 	if (options["secure-auth"] == "true")
@@ -138,12 +140,19 @@ void SessionImpl::open(const std::string& connect)
 	else if (options["secure-auth"] == "false")
 		_handle.options(MYSQL_SECURE_AUTH, false);
 	else if (!options["secure-auth"].empty())
-		throw MySQLException("create session: specify correct secure-auth option (true or false) or skip it");
+		throw MySQLException("create session: specify correct secure-auth option (true or false)");
 #endif
 
 	if (!options["character-set"].empty())
 		_handle.options(MYSQL_SET_CHARSET_NAME, options["character-set"].c_str());
 
+	if (options["reset"] == "true")
+		_reset = true;
+	else if (options["reset"] == "false")
+		_reset = false;
+	else if (!options["reset"].empty())
+		throw MySQLException("create session: specify correct reset option (true or false)");
+
 	// Real connect
 	_handle.connect(options["host"].c_str(),
 			options["user"].c_str(),
@@ -264,8 +273,10 @@ bool SessionImpl::hasTransactionIsolation(Poco::UInt32 ti) const
 
 void SessionImpl::reset()
 {
-	if (_connected)
+	if (_connected && _reset)
+	{
 		_handle.reset();
+	}
 }
 
 

doc/99100-ReleaseNotes.page

@@ -13,6 +13,8 @@ AAAIntroduction
   - GH #2791: allow pre-allocation of the buffer in Poco::LogStreamBuf.
   - GH #2816: Modernise TLS configuration
   - GH #2818: Add getSpecifiedPort() method in Poco::URI.
+  - MySQL: resetting the session when putting it back into a SessionPool is now optional
+    (and disabled by default) due to a bug in MySQL messing up the character encoding when doing so.
 
 
 !!!Release 1.10.0