Provider Interface Changes in Q3 2010

Motivation

It is often necessary to send additional data to the underlying data provider. This can be any form of meta-data that is not part of the appointments themselves. The interface defined by the original SchedulerProviderBase abstract base class did not provide any means of doing so. Side-channels, such as the Session, had to be used to transfer such meta-data.

We also chose to simplify the retrieving of resources and it now requires implementing one method instead of two.

The Q3 2010 version of RadScheduler introduces a number of important changes that aim to resolve these issues while maintaining full compatibility with existing implementations.

Changes to the provider interface

1. The GetAppointments, Insert, Update and Delete methods now have overloads that take ISchedulerInfo as first parameter instead of RadScheduler.

2. A new GetResources method replaces GetResourceTypes and GetResourcesByType. It also takes ISchedulerInfo as first parameter.

3. The legacy methods are no longer abstract. A runtime exception will be throw if you don't implement either the new or the old version of each method.

public abstract class SchedulerProviderBase : ProviderBase
{
    // New methods
    public virtual IEnumerable<Appointment> GetAppointments(ISchedulerInfo schedulerInfo);
    public virtual void Insert(ISchedulerInfo schedulerInfo, Appointment appointmentToInsert);
    public virtual void Update(ISchedulerInfo schedulerInfo, Appointment appointmentToUpdate);
    public virtual void Delete(ISchedulerInfo schedulerInfo, Appointment appointmentToDelete);

    // Replaces both GetResourceTypes and GetResourcesByType
    public virtual IDictionary<ResourceType, IEnumerable<Resource>> GetResources(ISchedulerInfo schedulerInfo);

    // No change - returns a thread-safe wrapper of this provider instance
    public virtual SchedulerProviderBase Synchronized();

    // Legacy methods - used to be abstract
    public virtual IEnumerable<Appointment> GetAppointments(RadScheduler owner);
    public virtual IEnumerable<ResourceType> GetResourceTypes(RadScheduler owner);
    public virtual IEnumerable<Resource> GetResourcesByType(RadScheduler owner, string resourceType);
    public virtual void Insert(RadScheduler owner, Appointment appointmentToInsert);
    public virtual void Update(RadScheduler owner, Appointment appointmentToUpdate);
    public virtual void Delete(RadScheduler owner, Appointment appointmentToDelete);
} 

Public MustInherit Class SchedulerProviderBase Inherits ProviderBase
    ' New methods
    Public Overridable Function GetAppointments(schedulerInfo As ISchedulerInfo) As IEnumerable(Of Appointment)
    End Function
    Public Overridable Sub Insert(schedulerInfo As ISchedulerInfo, appointmentToInsert As Appointment)
    End Sub
    Public Overridable Sub Update(schedulerInfo As ISchedulerInfo, appointmentToUpdate As Appointment)
    End Sub
    Public Overridable Sub Delete(schedulerInfo As ISchedulerInfo, appointmentToDelete As Appointment)
    End Sub

    ' Replaces both GetResourceTypes and GetResourcesByType
    Public Overridable Function GetResources(schedulerInfo As ISchedulerInfo) As IDictionary(Of ResourceType, IEnumerable(Of Resource))
    End Function

    ' No change - returns a thread-safe wrapper of this provider instance
    Public Overridable Function Synchronized() As SchedulerProviderBase
    End Function

    ' Legacy methods - used to be abstract
    Public Overridable Function GetAppointments(owner As RadScheduler) As IEnumerable(Of Appointment)
    End Function
    Public Overridable Function GetResourceTypes(owner As RadScheduler) As IEnumerable(Of ResourceType)
    End Function
    Public Overridable Function GetResourcesByType(owner As RadScheduler, resourceType As String) As IEnumerable(Of Resource)
    End Function
    Public Overridable Sub Insert(owner As RadScheduler, appointmentToInsert As Appointment)
    End Sub
    Public Overridable Sub Update(owner As RadScheduler, appointmentToUpdate As Appointment)
    End Sub
    Public Overridable Sub Delete(owner As RadScheduler, appointmentToDelete As Appointment)
    End Sub
End Class 

Upgrading existing providers

Your existing provider implementations will continue to work without change. The upgrade can be done if and when necessary.

1. Replace the "RadScheduler owner" parameter with "ISchedulerInfo schedulerInfo"

2. Merge GetResourceTypes and GetResourcesByType into a single method overriding GetResources

See Also

• Sending Additional Information to the Provider

• Sending Additional Information to the Web Service