Architecture - eXist: A NoSQL Database and Application Development Platform - page 70

Figure 4-4. eXist client/server database architecture
Web Application Platform Architecture
When developing a web application, you typically have two domains of code: server-
side and client-side . Server-side code is executed on the web application server itself
(in this case, eXist), while client-side code is executed by the client (typically a web
browser).
eXist can serve as a complete web application platform whereby your applications are
developed in one or more of the following server-side XML languages: XQuery,
XSLT, XProc, and XForms.
Upon receiving a web request from a client, eXist processes your server-side code and
generates a response containing the results of the processing (which may even
include further client-side code) for the client. The response sent to the client could
be anything, but typically will be in one or more of these formats: HTML5, XHTML,
XML, JSON, XForms, CSS, or a variety of binary formats (e.g., images for display in a
page).
To understand how to develop web applications with eXist, see Chapter 9 . When
eXist is deployed as a web application platform there are many components that you
may or may not wish to use, depending on your web application; however, it is rec‐
ommended (as described in “Reducing the Attack Surface” on page 177 ) that you dis‐
able those that you are not using. Regardless of your application, if you wish to use
eXist as a web application platform, it will require the use of a Java web application
server , and here you have two main choices for deployment: