The following is a catalog of all parameters (arguments supplied in the HTTP query string) supported by DLXS middleware. These parameters apply to all middleware developed for DLXS collections/classes, as well as existing non-DLXS middleware when it undergoes significant rework to bring it into the DLXS framework. The goals for this are:

1. to provide consistency for statistics gathering;
2. to provide consistency for interoperability between collections (and between digital libraries in the future);
3. and to provide a definition that is scalable for future growth.

All keywords used for CGI parameters and region names should adhere to the following naming principles:

1. They should not be too short (and thus cryptic) and yet not too long (and thus create browser problems).
2. They should be be lowercase.
3. They should be alphanumeric only, and include no punctuation.

Searches

Most searches make use of one of the three basic search types: simple, boolean, and proximity. They also use "Region" names derived from the XML or SGML and are reflected in the DLXS TerminologyMapper map file where they are mapped to XPAT region names. The automatic generation of XPAT queries from these mapped parameters is implemented using the DLXS QueryFactory module.

The existing list of region names will be expanded as DLXS continues to develop a class-based architecture. Typically, DLXS Collection Managers review existing region naming across similar classes before defining new region names.

An unimplemented proposal to make statistics gathering more precise proposes the "nostats" CGI parameter to screen out search results from a usage statistics gathering process. For example, where the search would otherwise produce multiple "hits" when viewing different parts of a result.

Browses

Note that the following parameters were derived from existing non-DLXS browse categories and that currently none are implemented in DLXS middleware. As these browse categories are implemented in DLXS middleware their descriptions will be expanded in more detail.

Views

Note that the following parameters were derived from non-DLXS view categories and that, consequently, many are not yet implemented in DLXS middleware.

Collection Identification

Any additions or changes to collection parameters must be reviewed by the Architecture group.

Page

Any additions or changes to page parameters must be reviewed by the Architecture group.

Misc

Any additions or changes to miscellaneous parameters must be reviewed by the Architecture group.