Enable data masking

[tpflueger]

Adds a method that would enable masking row values on export.

[adriancs2]

Thank you very much

[adriancs2]

this code changes has integrated into release version of v2.3.9
all nuget packages have already updated to this version.
Thank you

[adriancs2]

@tpflueger I have written a documentation/wiki page attempting to explain this feature.

Wiki: https://github.com/MySqlBackupNET/MySqlBackup.Net/wiki/Adjust-Column-Value

As you are the original code contributor of this feature, I would like to invite you to review the wiki page and determine if any meaningful points have been omitted. Thank you again.

And my apologies for the "late" response to this pull request :)

[adriancs2]

@tpflueger Hi tpflueger, can you share some code snippet of how you use this feature on masking data? I would like to share your idea at the wiki page. thank you very much.

[tpflueger]

@adriancs2 The documentation looks great! Our use case was for masking data for privacy in environments other than production. An example below utilizing Faker to generate fake data.

private object MaskUserTable(ColumnWithValue columnInfo)
{
    switch (columnInfo.ColumnName)
    {
        case "EmailAddress":
            {
                var username = Faker.Internet.UserName(name);
                return username;
            }
        default:
            return columnInfo.Value;
    }
}

private object MaskColumnValue(ColumnWithValue columnInfo)
{
    switch (columnInfo.TableName)
    {
        case "users":
            return MaskUserTable(columnInfo);
        default:
            return columnInfo.Value;
    }
}

[adriancs2]

@tpflueger Hi Tyler. There is a change of how this feature is handled. below is the new sample code.
https://github.com/MySqlBackupNET/MySqlBackup.Net/blob/master/source%20code/TestDebugASPNET/pages/QuickTestAdjustColumnValue.aspx.cs line:299
New version will be released soon.

[adriancs2]

@tpflueger Hi Tyler :D. The new version v2.6 is released. I have updated the wiki guideline specifically for this feature. You may read it at: https://github.com/MySqlBackupNET/MySqlBackup.Net/wiki/Adjust-Column-Value
and for the working example code, you may view the code example in the ASP.NET page:

https://github.com/MySqlBackupNET/MySqlBackup.Net/blob/master/source%20code/TestDebugASPNET/pages/QuickTestAdjustColumnValue.aspx.cs

line 285 at the method:

void ExportToFile(string dbName, string dumpFile, RowsDataExportMode mode)
{
    using (MySqlConnection conn = new MySqlConnection(_connectionString))
    {
        conn.Open();

        using (var cmd = conn.CreateCommand())
        {
            cmd.CommandText = $"USE `{dbName}`";
            cmd.ExecuteNonQuery();

            using (MySqlBackup mb = new MySqlBackup(cmd))
            {
                mb.ExportInfo.RowsExportMode = mode;
                mb.ExportInfo.RecordDumpTime = false;
                mb.ExportInfo.InsertLineBreakBetweenInserts = true;

                mb.ExportInfo.AddTableColumnValueAdjustment("member2", "name", MaskName);
                mb.ExportInfo.AddTableColumnValueAdjustment("member2", "email", MaskEmail);
                mb.ExportInfo.AddTableColumnValueAdjustment("member2", "username", MaskUsername);

                mb.ExportToFile(dumpFile);
            }
        }
    }
}

object MaskName(object obInput)
{
    return ...
}

object MaskEmail(object obInput)
{
    return ...
}

static object MaskUsername(object obInput)
{
    return ...
}