MySQL Bugs: #10281: Clone issue with MySqlConnection

Bug #10281	Clone issue with MySqlConnection
Submitted:	30 Apr 2005 16:00	Modified:	8 Jun 2005 21:55
Reporter:	Roberto Rabe	Email Updates:
Status:	Closed	Impact on me:	None
Category:	Connector / NET	Severity:	S2 (Serious)
Version:	1.0.4	OS:	Windows (XP Pro (SP2))
Assigned to:	Reggie Burnett	CPU Architecture:	Any

Description:
See Bug #7478 for original comment.

Cloning a connection throws an unhandled exception if the original MySqlConnection still has the default ConnectionString Hashtable values. 

How to repeat:
Simple/quick ConnectionTests NUnit test to throw exception:

[Test()]
public void TestConnectionClone()
{
	MySqlConnection c = new MySqlConnection();
	MySqlConnection clone = (MySqlConnection) ((ICloneable)c).Clone();
}

MySql.Data.MySqlClient.Tests.ConnectionTests.TestConnectionClone :
System.NullReferenceException : Object reference not set to an instance of an
object.

   at MySql.Data.MySqlClient.MySqlConnectionString.CreateConnectionString() in
\MySqlClient\ConnectionString.cs:line 300
   at MySql.Data.MySqlClient.MySqlConnectionString.GetConnectionString() in
\MySqlClient\ConnectionString.cs:line 261
   at MySql.Data.MySqlClient.MySqlConnection.get_ConnectionString() in
\MySqlClient\Connection.cs:line 172
   at MySql.Data.MySqlClient.MySqlConnection.System.ICloneable.Clone() in
\MySqlClient\Connection.cs:line 344
   at MySql.Data.MySqlClient.Tests.ConnectionTests.TestConnectionClone() in
\testsuite\connectiontests.cs:line 50

Suggested fix:
ConnectionString.CreateConnectionString() throws exception when looping through keys and gets to "charset" key:

/// <summary>
/// Uses the values in the keyValues hash to create a
/// connection string
/// </summary>
/// <returns></returns>
public string CreateConnectionString()
{
	string cStr = String.Empty;

	Hashtable values = (Hashtable)keyValues.Clone();
	Hashtable defaultValues = GetDefaultValues();

	if (!PersistSecurityInfo && values.Contains("password") )
		values.Remove( "password" );

	// we always return the server key.  It's not needed but 
	// seems weird for it not to be there.
	cStr = "server=" + values["host"] + ";";
	values.Remove("server");

	foreach (string key in values.Keys)
	{
		if (!values[key].Equals( defaultValues[key]))
			cStr += key + "=" + values[key] + ";";
	}

	return cStr;
}

Fix by checking for charset null (or any undefined value) in loop before grabbing values[key] to append to cStr.

Roberto

Could you send any example test suit for this bug with using CreateConnectionString() ?

Not sure why an additional test is needed for CreateConnectionString().  The error happens when clone is called and a connection string had not yet been set on the original connection.  The TestConnectionClone() is a really simple and quick test that shows the error.

Thanks!

Hmmm...maybe this was missed in my original post:

[Test()]
public void TestConnectionClone()
{
	MySqlConnection c = new MySqlConnection();
	MySqlConnection clone = (MySqlConnection) ((ICloneable)c).Clone();
}

That test was near the top of the original post.

Tested on Win 2000 Sp4, Microsoft Visual C# .NET , Connector .NET 1.0.4 Test case is in text.

Thank you for your bug report. This issue has been committed to our
source repository of that product and will be incorporated into the
next release.

If necessary, you can access the source repository and build the latest
available version, including the bugfix, yourself. More information 
about accessing the source trees is available at
    http://www.mysql.com/doc/en/Installing_source_tree.html

Additional info:

Fixed in 1.0.5

Documented in Connector/NET changelog.

I got the latest version with the command "bk clone http://mysql.bkbits.net/connector-net connector-net
". In this version the problem seems not to be fixed. Did you checkin the change already??
Thanks!