Plugins

Plugins

[This is preliminary documentation and is subject to change.]

The Plug-in system in TOPICA is used to encapsulate specialized application logic that migth only be used a single or few configurations. This allows each configuration to extend or override certain aspects of the standard functionality of the TOPICA framework.

Reasons for utilizing the TOPICA plug-in system

Plug-ins are useful in situations where the application logic is to large or complex to include in a single webform page. In situations such as this it could be a good solution to create a framework plug-in.

Plug-ins could also be used to contain application logic that should not be subject to random change in individual configurations.

Plug-ins usually contain application logic that might be used in multiple configurations. This could be integration with external systems, that are used by a wide range of applications.

Plug-ins have been used extensively to implement Integration between TOPICA applications and external systems, including Import and Export funtionality.

How to develop plug-ins for the TOPICA framework

The plug-ins are developed as dll's in the .Net framework. The framework plug-in must adhere to predefined interface specifications that allow for seamless integration wih the TOPICA framework. If the plug-in implements the specified interface any application logic can be included in the plug-in.

FormCommandHandler plug-ins are used to invoke functionality in a dll from a button that is integrated into a dynamic form. These plug-ins must implement the following interface in order to be recognized by the TOPICA framework:

Copy

public interface IFormCommandHandler: IPlugin
{
    /// <summary xmlns="http://ddue.schemas.microsoft.com/authoring/2003/5">
    /// Triggered to execute some command
    /// </summary>
    void Execute(Record record, FormContext formContext, ContextWrapper contextWrapper, string command);

    /// <summary xmlns="http://ddue.schemas.microsoft.com/authoring/2003/5">
    /// This method is called after the Execute finishes, the return value is reported to the end user
    /// </summary>
    string PostExecuteReport();
}

Data import plug-ins are used to import data into the TOPICA application.

NB: Import plug-ins are more or less a deprecated feature. Consider using SSIS packages instead!

Import plug-ins must implement the following interface in order to be compatible the TOPICA framework:

Copy

public interface IImport : IPlugin
{
    /// <summary>
    /// Defines a contract that importers should implement
    /// </summary>
    /// <param name="stream">Stream to the data that should be imported</param>
    /// <param name="systemInfoWrapper">Holds information about the system the Import is triggered from</param>
    /// <param name="importProgress">Delegate used for progress callback (can be used to stop the import)</param>
    /// <param name="customparams">Custom parameters for the Import</param>
    /// <returns>The outcome of the import</returns>
    ImportStatus Import(Stream stream, BaseContextWrapper systemInfoWrapper, ImportProgress importProgress, string customparams);

    /// <summary>
    /// Defines a contract that updaters should implement
    /// </summary>
    /// <param name="stream">Stream to the data that should be imported</param>
    /// <param name="systemInfoWrapper">Holds information about the system the Import is triggered from</param>
    /// <param name="importProgress">Delegate used for progress callback (can be used to stop the import)</param>
    /// <returns>The outcome of the import</returns>
    ImportStatus Update(Stream stream, BaseContextWrapper systemInfoWrapper, ImportProgress importProgress);

    /// <summary>
    /// Defines a contract that deleters should implement
    /// </summary>
    /// <param name="stream">Stream to the data that should be imported</param>
    /// <param name="systemInfoWrapper">Holds information about the system the Import is triggered from</param>
    /// <param name="importProgress">Delegate used for progress callback (can be used to stop the import)</param>
    /// <returns>The outcome of the import</returns>
    ImportStatus Delete(Stream stream, BaseContextWrapper systemInfoWrapper, ImportProgress importProgress);
}