Image retrieval
Several pages and components display images to the user. These images must be retrieved before they can be displayed.
For Duplicate Detect, you can write image request handlers to retrieve images from different image repositories. The Duplicate Detect image request handler is configured in the namespace XML. For more information about Duplicate Detect image request handlers, see Image request handlers.
Local
In local mode, the images are retrieved from the file system, which the Control Center must be able to access.
For an application to use local image retrieval, it must have access to the file system where the images are stored. The application must be able to access those files by using the same path that the Gateway Server uses to store the images. The path that is used by the Gateway Server is configured in its properties file.
Remote
In remote mode, a remote call to Transaction Server is used to retrieve images. To make a remote call to the Transaction Server, its IP address and port number must be known. To determine which Transaction Server instance to call, the component first tries to use the preferred Transaction Server that you configured. If you did not specify a preferred Transaction Server, the component then queries the available Transaction Server instances to find one to use.
Whenever an instance of the Transaction Server starts, it registers itself in FTM. When the user interface needs images, the registered Transaction Server instances are queried and the first one returned is used to retrieve the images. If the selected instance is not available for some reason, the next instance from the list that the query returns is tried. After an available instance is found, it is used until it becomes no longer available. When an instance becomes unavailable, the next instance in the list is used.
If you have a preference for which Transaction Server instance a specific component uses, specify it in the general configuration properties of the component. If a preferred Transaction Server is configured, it is tried before any other Transaction Server instances are tried. Configuring a preference provides a rudimentary way to balance the image retrieval load.
The registered instances of Transaction Server are shown on the platform components page. Use the server name that is displayed on the page for the value that you set in the preferred Transaction Server property. For more information about the page, see Platform components page.