Three-layer mashup app
This tutorial is based on the GoToAssist Alert and GoToAssist Inventory applications, which work as web services consisting of three layers:
- A user interface is provided by a flash application running in a browser. The application requires a tree that is clipped to certain bounds, zoomed to a certain level from the server, which it renders in a canvas on the browser. The application contains controls for zooming, panning, selecting nodes, and specifying queries that result in the resulting nodes being selected and visible in its viewport.
- An application that queries the backend for the network hierarchy, with hinting on what to fetch by the clipping request from the flash client. This second layer links the nodes into trees and applies a layout to the resulting trees. This result is cached for efficiency. It then delivers the list of nodes that match its clipped request to the client, with a limited amount of meta information about the nodes. The client may also request additional information about any individual node.
- The third layer is the core GoToAssist system, which the other layers access via the GoToAssist API.