Yahoo! Pipes

Pipes Plumbing

In any endeavor, it's important to know your tools. Next, we'll examine one of the modules in depth.

We used the Filter module earlier, and while it worked well in our simple example, it has features we can explore further.

First, look at the title bar of the module (see Figure 12).

Figure 12. 

You know about the connector "dot" at the center top of the title bar; that's for connecting the filter to an RSS source. But what about the three buttons on the right? The question mark button displays help information about the filter module, shown in the Yahoo! Pipes Help section at the bottom left of the Editor page.

The middle button is for minimizing the module, but not in the way you might expect. Instead of minimizing the module window entirely, it collapses the window to just its title bar. Some Pipes can become very complex, and since Yahoo! Pipes is an entirely graphical language, each new module eats up screen real estate. The minimize button unclutters the Pipes canvas. When collapsed, the middle button becomes a plus sign. Pressing this button re-expands the module window. There are also option buttons at the upper left of the Editor to "expand all" and "collapse all"—these provide a one-click method for uncluttering and recluttering the Pipes canvas.

The final button (the red "x") deletes the module. There's currently no undo function in Yahoo! Pipes, and there's no ...