HTML and CSS Reference
In-Depth Information
HTML5 has a more general-purpose alternative to cross-document messaging known as
channel messaging. It allows you to create as many message ports as you want, not only
between windows but also between any sorts of JavaScript object. Channel messaging
wasn't necessary to complete the application in this chapter, but if you think you'll find it
useful in your own applications, we've included a short introduction in
appendix F
.
4.4. Summary
In this chapter, you've learned about the new messaging APIs in HTML5, between pages
in different windows on the client, with cross-document messaging, and between client
and server, with server-sent events and WebSockets. You've also gained a practical under-
standing of how to use one of the new wave of web servers optimized for event-driven
communication, Node.js. With all this new knowledge you're well equipped to build the
next generation of web applications, based on lightweight, event-driven data communica-
tion between client and server, and you'll be able to join several such applications together
in client browsers in a lightly coupled way thanks to cross-document messaging.
In the next chapter, you'll move on to consider an application environment where saving
every byte makes a real difference: mobile web applications. HTML5 offers new capabilit-
ies that allow your application to keep working when no network is available.
