Notification Services—Creating a Notification Class, Content Formatter, and Notification Class Protocol

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Creating a Notification Class, Content Formatter, and Notification Class Protocol

A notification class named StockWatchNotifications, a content formatter named XsltFormatter, and two notification class protocols named File and SMTP are created in the CreateNotificationClass( ) method of Example 18-1. The code follows:

private static void CreateNotificationClass( )
{
  NotificationClass nc = 
    new NotificationClass(a, 
    "StockWatchNotifications");
  NotificationField nf;
  nf = new NotificationField(nc, "Symbol");
  nf.Type = "nvarchar(6)";
  nc.NotificationFields.Add(nf);
  nf = new NotificationField(nc, "Price");
  nf.Type = "float";
  nc.NotificationFields.Add(nf);
  ContentFormatter cf = new ContentFormatter
    (nc, "XsltFormatter");
  ContentFormatterArgument cfa;
  cfa = new ContentFormatterArgument
    (cf, "XsltBaseDirectoryPath");
  cfa.Value = a.BaseDirectoryPath + 
    @"\AppDefinition";
  cf.ContentFormatterArguments.Add(cfa);
  cfa = new ContentFormatterArgument(cf, "XsltFileName");
  cfa.Value = "StockWatch.xslt";
  cf.ContentFormatterArguments.Add(cfa);
  nc.ContentFormatter = cf;
  nc.DigestDelivery = true;
  ProtocolField pf;
 
  // add file notification class protocol
  NotificationClassProtocol ncpFile =
    new NotificationClassProtocol(nc, "File");
  pf = new ProtocolField(ncpFile, "Symbol");
  pf.FieldReference = "Symbol";
  ncpFile.ProtocolFields.Add(pf);
  pf = new ProtocolField(ncpFile, "Price");
  pf.FieldReference = "Price";
  ncpFile.ProtocolFields.Add(pf);
  nc.NotificationClassProtocols.Add(ncpFile);
 
  // add email notification class protocol
  NotificationClassProtocol ncpEmail =
    new NotificationClassProtocol(nc, "SMTP");
  pf = new ProtocolField(ncpEmail, "Subject");
  pf.SqlExpression = "'Stock watch: ' + CONVERT(nvarchar(30), GETDATE( ))";
  ncpEmail.ProtocolFields.Add(pf);
  pf = new ProtocolField(ncpEmail, "BodyFormat");
  pf.SqlExpression = "'html'";
  ncpEmail.ProtocolFields.Add(pf);
  pf = new ProtocolField(ncpEmail, "From");
  pf.SqlExpression = "'notification@StockWatchService.com'";
  ncpEmail.ProtocolFields.Add(pf);
  pf = new ProtocolField(ncpEmail, "Priority");
  pf.SqlExpression = "'Normal'";
  ncpEmail.ProtocolFields.Add(pf);
  pf = new ProtocolField(ncpEmail, "To");
  pf.SqlExpression = "DeviceAddress";
  ncpEmail.ProtocolFields.Add(pf);
  nc.NotificationClassProtocols.Add(ncpEmail);
  nc.ExpirationAge = new TimeSpan(1, 0, 0);
  a.NotificationClasses.Add(nc);
  Console.WriteLine("Added notification class: " + nc.Name);
}

The NotificationClass object represents a type of notification supported by a Notification Services application. A NotificationField object represents a field in a notification class schema. The notification class in this example has two fields—Symbol of type nvarchar(6) and Price of type float.

The NMO classes for managing notification classes and fields are described in Table 18-7.

Table 18-7. NMO classes for managing notification classes and fields

Class	Description
NotificationClass	Represents a notification class.
NotificationClassCollection	Represents a collection of notification classes as NotificationClass objects. The NotificationClasses property of the Application class returns the notification classes for the Notification Services application.
NotificationComputedField	Represents a computed field in a notification class schema.
NotificationComputedFieldCollection	Represents a collection of computed fields as NotificationComputedField objects. The NotificationComputedFields property of the NotificationClass class returns the computed fields for the notification class.
NotificationField	Represents a noncomputed field in a notification class schema.
NotificationFieldCollection	Represents a collection of fields as NotificationField objects. The NotificationFields property of the NotificationClass class returns the fields for the notification class.

A content formatter formats notifications for a notification class. Each notification class has one content formatter that can perform different formatting based on field values in the notification. The content formatter takes three arguments:

XsltBaseDirectoryPath

The root directory for all XSLT files.

XsltFileName

The name of the XSLT file used to transform raw notification data into formatted data for notification delivery.

DisableEscaping

An optional Boolean argument indicating that the event data contains either HTML or XML data preventing further transformation. The default value is false.

The NMO classes for managing content formatters are described in Table 18-8.

Table 18-8. NMO classes for managing content formatters

Class	Description
ContentFormatter	Represents a content formatter. The ContentFormatter property of the NotificationClass class returns the content formatter for the notification class.
ContentFormatterArgument	Represents a name-value pair for a content formatter initialization argument.
ContentFormatterArgumentCollection	Represents a collection of initialization arguments as ContentFormatterArgument objects. The ContentFormatterArguments property of the ContentFormatter class returns the initialization arguments for the content formatter.

A notification class protocol represents a delivery protocol for a notification class. A ProtocolField object represents a protocol header field used by some delivery protocols. Protocol field headers are different for file and email notification—examine the code and examine the file and email notifications shown in Figure 18-7 and Figure 18-8 to see the result of setting the protocol fields. The value of the ProtocolField object is set using either the SqlExpression or FieldReference property. This lets you use either a T-SQL expression or a notification field to define a protocol field value.

The NMO classes for managing protocols are described in Table 18-9.

Table 18-9. NMO classes for managing protocols

Class	Description
NotificationClassProtocol	Represents a delivery protocol for a notification class.
NotificationClassProtocolCollection	Represents a collection of notification class protocols as NotificationClassProtocol objects. The NotificationClassProtocols property of the NotificationClass class returns the delivery classes for the notification class.
ProtocolDefinition	Represents a custom delivery protocol.
ProtocolDefinitionCollection	Represents a collection of custom delivery protocols as ProtocolDefinition objects. The ProtocolDefinitions property of the Instance class returns the custom delivery protocols for the Notification Services instance.
ProtocolField	Represents a protocol header field.
ProtocolFieldCollection	Represents a collection of protocol header fields as ProtocolField objects. The ProtocolFields property of the NotificationClassProtocol class returns the protocol header fields for the delivery protocol.
ProtocolRetrySchedule	Represents a retry schedule interval.
ProtocolRetryScheduleCollection	Represents a collection of retry schedule intervals as ProtocolRetrySchedule objects. The ProtocolRetrySchedules property of the NotificationClassProtocol class returns the retry schedules for notifications sent using the delivery protocol.