Chapter 5. Oracle HTTP Server

The Oracle HTTP Server acts as the web server or listener for Oracle Application Server. Based on the Open Source Apache Web Server (Version 1.3 code base), the Oracle HTTP Server is the heart of Oracle Application Server, directing requests to the appropriate source for the requests. Requests for both static and dynamic content are processed through the Oracle HTTP Server. Static content is served from the local file system, while the Oracle HTTP Server redirects dynamic content requests to the appropriate executable resource.

Oracle isn't the first organization to use Apache as the web server component of their application server. Several others have also used Apache. So why is Apache such an attractive choice for a web server?

• Apache has an extremely flexible architecture; most of its functionality is provided by a set of plugged-in modules, or mods . You can add any desired functionality to Apache by creating an appropriate module. Oracle has created several custom mods for Oracle Application Server, as we'll discuss later in this chapter.

• Apache has a very flexible configuration system. Directives specified in a set of text-based configuration files are used to load any desired module and have it process requests using a variety of methods ”for example, by location, file type, or other indicators.

• Largely because of its large installed base (more than 64% of all Internet web sites at the time of this writing), Apache has become a very stable and secure web server. Combine this with the ability to leverage a large existing Apache administrator workforce, and it makes sense to use Apache's existing code base as a basis for the Oracle HTTP Server.

This chapter delves into the workings of the Oracle HTTP Server. It starts with an overview of the Apache architecture. Next, it covers the modules Oracle bundles with the Oracle HTTP Server that aren't part of a standard Apache distribution. It touches on how security and management services hook into the Oracle HTTP Server, and it finishes up with a look at integrating third-party listeners with the Oracle HTTP Server.