Gadget Web Services are the building blocks of the Plumtree Corporate Portal, and can provide access to virtually any application or Internet service.
Gadget Web Service is any Web application that returns HTML or XML over HTTP.Each Gadget Web Service is self-contained and executes its particular functionality in a separate process. Most Gadget Web Services connect to a back-end application for data
or functionality.
Gadget Web Services can connect with almost any back-end application to provide access to the applications and information users need every day. Users choose the
layout of their own My Pages and can access Gadget Web Services
from anywhere they use the Web. Beginning with Plumtree 4.5, users can also view the portal and supported Gadget Web Services on handheld devices and cellular phones.
THE PLUMTREE PORTAL ARCHITECTURE
The Plumtree Portal architecture is based on the open standards of the Web. The basic components of this architecture are:
o Portal Server (PS) — main Plumtree Portal server
o Gadget Server (GS) — server that hosts Gadget Web Services
o Image Server — server that hosts images
Gadget Web Services communicate with the Portal Server (PS) via HTTP, by reading and setting headers.
When a browser requests a My Page from the portal, the PS makes simultaneous requests to each Gadget Server (GS). Each GS reads the current user’s preferences from the HTTP headers sent by the PS, and sends back the appropriate HTML or
XML. The PS then transforms the XML (if any), and inserts the HTML into the table that makes up the My Page. Any images located on separate Image Servers are displayed by the browser.
Plumtree’s Massively Parallel Portal Engine (MPPE) allows the PS to access each GS in parallel, resulting in faster,more efficient processing of Portal pages.
THE GADGET GATEWAY
In the Plumtree Portal architecture, the Portal Server (PS) acts as a gateway server for Gadget Servers (GS). “gateway server” acts as a middleman, brokering transactions between a client computer and another server (an origin server”). This configuration is typically used to serve content to clients that would otherwise be unable to access
the origin server, but it may also be used to impose additional security restrictions on the client. The gateway server
hides the existence of the origin server; to the end user, the content appears to come directly from the gateway server.
This architecture makes the PS the single point of access for Gadget Web Service content, and allows Gadget Servers to
reside on a private network or behind a firewall. As long as the PS can connect to the Gadget Server, users can view the content, even if they cannot access it directly. To
the browser, the PS appears to be the origin server.
