Cinchoo – Allow multi-instance application

Multi-Instance Application

Cinchoo is an application framework for .NET. One of the main functionality it provides to users is application configuration management. It also offers few other key functionalities like Common ApplicationHost, BCL etc.

When you choose to use this library in your application, it will inherently allow only one instance of your application running at any time. This is the default behavior. When you run the second instance, it will throw below application error and followed by application termination.

Already another instance of this application running.

This behavior can be override able to allow more than one instance of your application can be runnable at any time. There are couple of ways you can do so.

Programmatically

This section illustrates on how to allow multiple instances of your application run at the same time. Simply subscribe to ChoApplication.ApplyGlobalApplicationSettingsOverrides event as below

class Program
{
    static void Main(string[] args)
    {
        ChoApplication.ApplyGlobalApplicationSettingsOverrides += new EventHandler<ChoEventArgs<ChoGlobalApplicationSettings>>(ChoApplication_ApplyGlobalApplicationSettingsOverrides);

        ChoConsole.PauseLine();
    }

    static void ChoApplication_ApplyGlobalApplicationSettingsOverrides(object sender, ChoEventArgs<ChoGlobalApplicationSettings> e)
    {
        e.Value.ApplicationBehaviourSettings.SingleInstanceApp = false;
    }
}

Configuration

This section illustrates how to make this through via configuration. Open the ChoCodeFrx.xml file. Look for singleInstanceApp attribute and assign ‘false’ as value. See sample below

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <globalApplicationSettings applicationId="ConfigFileOverride.Test.exe" eventLogSourceName="ConfigFileOverride.Test.exe">
    <behaviourSettings hideWindow="false" bringWindowToTop="false" alwaysOnTop="false" runAtStartup="false" runOnceAtStartup="false" singleInstanceApp="true" activateFirstInstance="false" showEnvironmentSelectionWnd="true" />
    ...
  </globalApplicationSettings>
  <metaDataFilePathSettings>
    ...
  </metaDataFilePathSettings>
</configuration>

PS: Make sure these initializations happens at the application entry point. In Windows Service, the event subscriptions are done at OnStart() method in ServiceBase subclass. In ASP.NET, the subscriptions are done in Application_Start() in Global.aspx file.

Cinchoo – Configuration Framework, Part 31

Disable logging

Cinchoo is an application framework for .NET. One of the main functionality it provides to users is application configuration management. Application configuration is the information that an application reads and/or writes at run-time from the source.

Please visit jump start article [Cinchoo - Simplified Configuration Manager] for more information about Cinchoo configuration manager.

In this section, I’ll show to disable logging of Cinchoo framework produces. Open a app.config file from your project. Add the below section

<configuration>
 <system.diagnostics>
   <switches>
     <add name="ChoSwitch" value="0" />
   </switches>
 </system.diagnostics>
</configuration>

ChoSwitch is a TraceSwitch, you can assign different levels to it to specify the types of trace or debug messages the application outputs. Setting the value to “0” will disable all the logging of the framework.

Other possible values can be assigned to control the output of the logs

  • 0 – Off
  • 1 – Error
  • 2 – Warning
  • 3 – Info
  • 4 – Verbose

Cinchoo – Configuration Framework, Part 30

Consume configuration values from any database.

Download Sample (Zip)

Cinchoo is an application framework for .NET. One of the main functionality it provides to users is application configuration management. Application configuration is the information that an application reads and/or writes at run-time from the source.

Please visit jump start article [Cinchoo - Simplified Configuration Manager] for more information about Cinchoo configuration manager.

In this section, I’ll detail about new configuration section handler, DbGenericeKeyValueConfigurationSection. It is generic database configuration section handler to read and store configuration data in any database. It eliminates creating new configuration section handler for each targeted database. All you need ADO.NET driver for the corresponding database to work with this handler. This section handler sufficient enough to interact with any database to read/store configuration data. Only downside of this handler is that all the values are converted to string before storing in the database.

Here are steps to work with this section handler

  • Define a table similar to the below schema. The table name can be given anything. This configuration handler needs a table with 2 columns. First column (KEY) holds the configuration parameter names. Must be VARCHAR(50), where length must be minimum of 50. Second column (VALUE) holds the configuration parameter values. It can be size of any. By default, this handler looks for KEY, VALUE as columns. The names of these columns can be given any. In this case, it must be passed as parameter to the configuration object. Will discuss this later about passing these parameters to the configuration object.
CREATE TABLE TEST_CONFIG
(
    [KEY] VARCHAR (50) NOT NULL,
    VALUE VARCHAR (100),
    PRIMARY KEY ([KEY])
)
  • Define configuration object targeted for Sqlite database as below
[ChoDbGenericKeyValueConfigurationSection("dbApplicationSettings",
@"CONNECTION_STRING='Data Source=.\SqliteTest.db;Version=3;Pooling=True;Max Pool Size=100;';
 TABLE_NAME=TEST_CONFIG;PROVIDER_ASSEMBLY_FILE_PATH=C:\Program Files\System.Data.SQLite\2010\bin\System.Data.SQLite.dll;PROVIDER_NAMESPACE=System.Data.SQLite;
 LAST_UPDATE_DATETIME_KEY_NAME=''", Silent = true)]
public class DbApplicationSettings : ChoConfigurableObject
{
 [ChoPropertyInfo("name", DefaultValue = "Mark")]
 public string Name;

 [ChoPropertyInfo("address", DefaultValue = "10 River Road, Edison NJ 08820")]
 public string Address;

 protected override void OnAfterConfigurationObjectLoaded()
 {
 Console.WriteLine(this.ToString());
 }
}

This configuration object must be decorated with ChoDbGenericKeyValueConfigurationSectionAttribute.

First parameter is the configElementPath, a xpath to the configuration section in the [appName].exe.xml file.

Second parameter is the configObjectAdapterParams, parameter list in key-value pairs format separated by ‘;’ character. (PS. If any value contains ‘;’ character, the whole value must be surrounded by single quote in order to escape it.) Below are the list of applicable parameters needed by this section handler

  1. CONNECTION_STRING (string) – Required. ADO.NET connection string to the database.
  2. TABLE_NAME (string) – Required. Configuration table name.
  3. PROVIDER_ASSEMBLY_FILE_PATH (string) – Optional. Only specify if the ADO.NET assembly is not referenced in the project. File path to the ADO.NET assembly if not in GAC. Otherwise, fully qualified assembly name.
  4. PROVIDER_NAMESPACE (string) – Required. Namespace of the ADO.NET provider (Ex. for Sqlite, it is System.Data.Sqlite)
  5. KEY_COLUMN_NAME (string) – Optional. Default is ‘KEY’. If you have different key column name, please specify it here.
  6. VALUE_COLUMN_NAME (string) – Optional. Default is ‘VALUE’. If you have different value column name, please specify it here.
  7. LAST_UPDATE_DATETIME_KEY_NAME (string) – Optional. Default is Empty string. In such case, this provider checks the configuration values for any changes in the underlying table. If you specify a valid key name, it must carry the value as timestamp. To notify the values changes by touching this value to last updated time stamp.
  8. PARAM_PREFIX_CHAR (char) – Optional. Default is ‘@’.
  9. TRUNCATE_VALUE_DATA (bool) – Optional. Default is True.  It will truncate the value if it is over the Value column size.

The above two parameters can be hard-coded in the code and also be modifiable through configuration. Here is how you can modify them through configuration. Open the [AppName].exe.xml file under Config folder

<?xml version="1.0" encoding="utf-8"?>
<configuration>
 <configSections>
 <section name="dbApplicationSettings" type="Cinchoo.Core.Configuration.ChoDictionarySectionHandler, Cinchoo.Core" />
 </configSections>
 <dbApplicationSettings cinchoo:configObjectAdapterType="Cinchoo.Core.Configuration.ChoDbGenericKeyValueConfigStorage, Cinchoo.Core" xmlns:cinchoo="http://schemas.cinchoo.com/cinchoo/01/framework">
 <cinchoo:configObjectAdapterParams xmlns:cinchoo="http://schemas.cinchoo.com/cinchoo/01/framework"><![CDATA[CONNECTION_STRING='Data Source=.\SqliteTest.db;Version=3;Pooling=True;Max Pool Size=100;';
 TABLE_NAME=TEST_CONFIG;PROVIDER_ASSEMBLY_FILE_PATH=C:\Program Files\System.Data.SQLite\2010\bin\System.Data.SQLite.dll;PROVIDER_NAMESPACE=System.Data.SQLite;
 LAST_UPDATE_DATETIME_KEY_NAME='']]></cinchoo:configObjectAdapterParams>
 </dbApplicationSettings>
</configuration>

Now lets try to create and consume the above configuration object. Below code shows how to consume and modify the object members

static void Main(string[] args)
{
    DbApplicationSettings DbApplicationSettings = new DbApplicationSettings();

    ChoConsole.PauseLine();
}

Compile and run this sample to see the output stored in the database.

That’s it folks, it is as easy as to store and consume Configuration values in any databases.

Cinchoo – Configuration Framework, Part 29

Support of Complex Object as configuration value

Download Sample (Zip)

Cinchoo is an application framework for .NET. One of the main functionality it provides to users is application configuration management. Application configuration is information that an application reads and/or writes at run-time from the source.

Please visit jump start article [Cinchoo - Simplified Configuration Manager] for more information about Cinchoo configuration manager.

In this section, I’ll detail about new feature, using and saving custom user defined object as configuration values. So far Cinchoo framework supports only scalar text values. It limits the configuration object member values from having any complex objects.

In standard .NET framework, it is not supported in straight way. You will have to create custom configuration section and put a plumbing code to parse the values. In Cinchoo framework, it is simplified to handle the complex objects as configuration values.

Here is how you can define configuration members to support custom user defined type

[ChoNameValueConfigurationSection("appSettings")]
public class AppSettings : ChoConfigurableObject
{
	[ChoPropertyInfo("name", DefaultValue = "Tom")]
	public string Name;

	[ChoPropertyInfo("address", DefaultValue="10, River Road, Piscataway, NJ 08880 && New York")]
	public ChoCDATA Address;

	[ChoPropertyInfo("employer", DefaultValue = "<Sample>ABCD Inc.</Sample>")]
	public string Employer;

	[ChoPropertyInfo("department")]
	public Department Department;

	protected override void OnAfterConfigurationObjectLoaded()
	{
		Console.WriteLine(ToString());
	}
}

In the above sample configuration object, Department member is defined as Department type, it is defined as below

[ChoXmlSerializerConverter(typeof(Department))]
public class Department : INotifyPropertyChanged
{
	private int _deptCode;

	[XmlAttribute("deptCode")]
	public int DeptCode
	{
		get { return _deptCode; }
		set
		{
			_deptCode = value;
			RaisePropertyChanged("DeptCode");
		}
	}

	private string _deptName;

	[XmlAttribute("deptName")]
	public string DeptName
	{
		get { return _deptName; }
		set
		{
			_deptName = value;
			RaisePropertyChanged("DeptName");
		}
	}

	public event PropertyChangedEventHandler PropertyChanged;

	protected void RaisePropertyChanged(string propertyName)
	{
		if (propertyName.IsNullOrWhiteSpace()) return;

		PropertyChangedEventHandler propertyChanged = PropertyChanged;
		if (propertyChanged != null)
			propertyChanged(this, new PropertyChangedEventArgs(propertyName));
	}
}

Key things to remember when you define custom object in order to use in configuration object

  • Should be decorated as ChoXmlSerializerConverter which helps to serialize the object to Xml string.
  • Must implement INotifyPropertyChanged in order to notify member changes to Configuration Manager.
  • Decorate appropriate Xml serialization attribute to its members (ie. XmlAttribute, XmlElement etc)

Now lets try to create and consume the above configuration object. Below code shows how to consume and modify the object members

static void Main(string[] args)
{
	AppSettings appSettings = new AppSettings();

	//Modify the members
	appSettings.Address.Value = "11, Oak Road, Woodbridge, NJ 08827";
	appSettings.Employer = "<Sample1>ZZZ1 Inc.</Sample1>";
	if (appSettings.Department == null)
		appSettings.Department = new Department() { DeptCode = 10, DeptName = "Comp Sc." };
	else
		appSettings.Department.DeptCode = appSettings.Department.DeptCode + 20;

	ChoFramework.Shutdown();
}

If you compile and run this sample, the output of the configuration will be seen as below

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <section name="appSettings" type="Cinchoo.Core.Configuration.ChoNameValueSectionHandler, Cinchoo.Core" />
  </configSections>
  <appSettings>
    <add key="name" value="Tom" />
    <add key="address">
      <value><![CDATA[11, Oak Road, Woodbridge, NJ 08827]]></value>
    </add>
    <add key="employer">
      <value>
        <Sample1>ZZZ1 Inc.</Sample1>
      </value>
    </add>
    <add key="department">
      <value>
        <Department deptCode="11" deptName="Comp Sc." />
      </value>
    </add>
  </appSettings>
</configuration>

That’s it folks, it is as easy as to store and consume custom user defined member in Configuration object.

Cinchoo – Configuration Framework, Part 28

Support of CDATA / Xml as configuration value

Download Sample (Zip)

Cinchoo is an application framework for .NET. One of the main functionality it provides to users is application configuration management. Application configuration is information that an application reads and/or writes at run-time from the source.

Please visit jump start article [Cinchoo - Simplified Configuration Manager] for more information about Cinchoo configuration manager.

In this section, I’m going to detail about new feature, using and saving CDATA / Xml  as configuration values. So far Cinchoo supports the configuration object member values as simple text values. It limits the configuration object member values from having any complex text.

In standard .NET framework, it is not supported in straight way. You will have to create custom configuration section and put a plumbing code to parse the values. In Cinchoo, it is simplified to handle CDATA/Xml values.

Here is how you can define configuration members to support CDATA / Xml values

[ChoNameValueConfigurationSection("appSettings")]
public class AppSettings : ChoConfigurableObject
{
	[ChoPropertyInfo("name", DefaultValue = "Tom")]
	public string Name;

	[ChoPropertyInfo("address", DefaultValue="10, River Road, Piscataway, NJ 08880 && New York")]
	public ChoCDATA Address;

	[ChoPropertyInfo("employer", DefaultValue = "<Sample>ABCD Inc.</Sample>")]
	public string Employer;
}

In the above sample configuration object, Address member defined as ChoCDATA type to accommodate CDATA value. Employer member is defined as string type, to hold the xml value. Cinchoo automatically checks the configuration member value for any xml tags present, if it does then the section value will be created as Xml element, otherwise it will be created as Xml attribute.

Now lets try to create and consume the above configuration object. Below code shows how to consume and modify the object members

static void Main(string[] args)
{
	AppSettings appSettings = new AppSettings();

	//Modify the members
	appSettings.Address = new ChoCDATA("11, Oak Road, Woodbridge, NJ 08827");
	appSettings.Employer = "<Sample1>ZZZ1 Inc.</Sample1>";

	Console.WriteLine(appSettings.ToString());
	ChoFramework.Shutdown();
}

Since Address is CDATA member, any modification must be done by creating new ChoCDATA object with new value and assign to it. And for the Employer member, it is straight forward to modify. Cinchoo framework will take care of it under the hood.

If you compile and run this sample, the output of the configuration will be seen as below

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <section name="appSettings" type="Cinchoo.Core.Configuration.ChoNameValueSectionHandler, Cinchoo.Core" />
  </configSections>
  <appSettings>
    <add key="name" value="Tom" />
    <add key="address">
      <value><![CDATA[11, Oak Road, Woodbridge, NJ 08827]]></value>
    </add>
    <add key="employer">
      <value>
        <Sample1>ZZZ1 Inc.</Sample1>
      </value>
    </add>
  </appSettings>
</configuration>

That’s it folks, it is as easy as to store and consume CDATA / Xml values in Configuration object.

Cinchoo – ConfigurationManager Tips 1

Cinchoo is the application framework for .NET. One of the main functionality it provides to the users is application configuration management. Application configuration is the information that application reads and/or writes at run-time from the source. Please take a look at ‘Cinchoo – Simplified Configuration Manager’ jump start article on using configuration framework in your application.

In this section, I’ll talk about a way to hook up the existing configuration files to your files through application configuration file. And how to set environment specific configuration files to the applications.

For more up to date information about this article, please visit the below CodeProject link

Cinchoo – ConfigurationManager Tips 1

Cinchoo – Using a SQL Server database as a configuration source, Part 2

Cinchoo is an application framework for .NET. One of the main functionality it provides to users is application configuration management. Application configuration is information that an application reads and/or writes at run-time from the source.

Please visit jump start article [Cinchoo - Simplified Configuration Manager] for more information about Cinchoo configuration manager.

This is the second part of [Cinchoo - Using SQLServer database as configuration source] article. So far we learned about using SQL Server database as configuration source in a polling approach. Cinchoo configuration manager polls for the change in the underlying table for every elapsed interval (configurable). This approach is ideal in a situation where SQL Server query notification service is not available or is turned off by administrators.

In this section, I’m going to detail you about using SQL Server database as configuration source for your applications. More commonly all the .NET application configuration are kept in files as XML format. It has the limitation, such as maintaining them for each application separately, potential disk corruption by many applications due to access etc. This may not fit in enterprise world.  In a enterprise application development, there may be requirement to centralize these configuration parameters in database to better serve, manage and control them. Cinchoo framework opens the possibility of extending the configuration source to various medium. A SQL Server database is one of the mediums to store the application configurations.

In this approach, we are going to leverage SQL Server query notification service for change notification. It is available in SQL Server 2005+/ADO.NET 2.0.

For more details on this configuration source, please visit the code project article below

Cinchoo – Using a SQL Server database as a configuration source, Part 2

Cinchoo – Using SQLServer database as configuration source

Cinchoo is an application framework for .NET. One of the main functionality it provides to users is application configuration management. Application configuration is information that an application reads and/or writes at run-time from the source.

Please visit jump start article [Cinchoo - Simplified Configuration Manager] for more information about Cinchoo configuration manager.

In this section, I’m going to detail you about using SQLServer database as configuration source for your applications. More commonly all the .NET application configuration are kept in files as XML format. It has the limitation, such as maintaining them for each application separately, potential disk corruption by many applications due to access etc. This may not fit in enterprise world.  In a enterprise application development, there may be requirement to centralize these configuration parameters in database to better serve, manage and control them. Cinchoo framework opens the possibility of extending the configuration source to various medium. A SQL Server database is one of the mediums to store the application configurations.

For more details on this configuration source, please visit the code project article below

Cinchoo – Using SQLServer database as configuration source

Cinchoo – Configuration framework, part 27

Using Converters

Download source files (Require .NET 4.0 / Visual Studio 2010)

Cinchoo configuration framework takes care of converting most of the intrinsic type configuration object members from text value like string to int, string to enum etc. In cases where you have custom type members, you will have to use converters to convert the text value to object. Cinchoo support the following types of converters

  1. System.ComponentModel.TypeConverter – For more information about it, visit ‘How to: Implement a TypeConverter
  2. System.Windows.Data.IValueConverter
  3. Cinchoo.Core.IChoValueConverter – It is similar interface to IValueConverter.

TypeConverters can be specified two ways using ChoTypeConverterAttribute 

  1. At each object member level – Will take priority over second option
  2. At the object type level

Lets go over with sample configuration object defined below

[ChoNameValueConfigurationSection("appSettings")]
public class AppSettings : ChoConfigurableObject
{
    [ChoPropertyInfo("name", DefaultValue = "Raj")]
    public string Name;

    [ChoPropertyInfo("address", DefaultValue = "21, Melbloum Lane, Edison NJ 08837")]
    public string Address;

    [ChoPropertyInfo("Color", DefaultValue = "Yellow")]
    public ConsoleColor Color;

    [ChoPropertyInfo("height", DefaultValue = "5.6")]
    public double Height;

    [ChoPropertyInfo("SSN", DefaultValue = "111-00-3333")]
    [ChoTypeConverter(typeof(SSNConverter))]
    public string SSN;

    [ChoPropertyInfo("Location", DefaultValue = "10, 12")]
    public Point Location;

    [ChoAfterConfigurationObjectLoadedHandler]
    public void AfterConfigurationObjectLoadedHandler(object sender, ChoConfigurationObjectEventArgs e)
    {
        Console.WriteLine(sender.ToString());
    }
}

In here,

  • Color is of ConsoleColor enum type. As I mentioned earlier, it is implicitly taken care by Cinchoo framework to read/store the value as string.
  • SSN is of string type, expects values in specific format (000-00-0000). It is decorated with member level type converter ‘SSNConverter’
  • Location is of Point type. But Point class bounded to PointConverter as below. No need to specify at the member level.

SSNConverter Implementation

public class SSNConverter : TypeConverter
{
    private static readonly Regex _ssnRegex = new Regex(@"^[0-9][0-9][0-9]\-[0-9][0-9]\-[0-9][0-9][0-9][0-9]$|^[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]$", RegexOptions.Compiled);
    private static readonly Regex _noSSNRegex = new Regex(@"^[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]$", RegexOptions.Compiled);
    public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
    {
        return sourceType == typeof(string);
    }
    public override object ConvertFrom(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value)
    {
        if (value != null && value is string)
        {
            string ssnValue = value as string;
            if (_ssnRegex.IsMatch(ssnValue))
                return ssnValue;
            else if (_noSSNRegex.IsMatch(ssnValue))
                return "{0}-{1}-{2}".FormatString(ssnValue.Substring(0, 2), ssnValue.Substring(2, 4), ssnValue.Substring(4, 7));
        }
        throw new ArgumentException("Invalid '{0}' SSN value passed.".FormatString(value));
    }
    public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
    {
        return destinationType == typeof(string);
    }
    public override object ConvertTo(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value, Type destinationType)
    {
        return (string)value;
    }
}

PointConverter Implementation

[ChoTypeConverter(typeof(Point))]
public class PointConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (value != null && value is string)
        {
            if (targetType == typeof(Point))
            {
                int x = 0, y = 0;
                string inValue = value as string;
                string[] parts = inValue.SplitNTrim(',');
                if (parts.Length >= 1)
                    x = System.Convert.ToInt32(parts[0]);
                if (parts.Length >= 2)
                    y = System.Convert.ToInt32(parts[1]);
                return new Point(x, y);
            }
        }
        return value;
    }
    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (value != null && value is Point)
        {
            if (targetType == typeof(string))
            {
                Point inValue = (Point)value;
                return "{0}, {1}".FormatString(inValue.X, inValue.Y);
            }
        }

        return value;
    }
}

You can use any existing TypeConverter / IValueConverter in your application. Try for yourself. Thanks.