GoHTTP System Description

The currently available version is 2.01.9-N. See Distribution for how to obtain a copy.

See the history file for a list of the revisions, additions, and bug fixes.

• Support ImageMaps. (a.k.a. Active Maps, 'Clickable' Maps)
  
  • Support for a "direct-to-map" URL with imagemap (bypasses imagemap.cnf)
    
  • Support for "completing" relative URLs within a map description file.
    
  • Support for handling local URLs by simply handing back the document, as in the CERN server.
    
  • Support for "CIRCLE" regions, in addition to the previously supported "CIRC".
    ("x1,y1 x2,y2" where x2,y2 is a point on the circumference, as opposed to "x1,y1 r" where r is the integer radius)
  • Support for "POLY" regions, as well as the new "POINT" method.
  • Should now be able to accept any MAP file created for NCSA's imagemap processor.
• Common Log Format logging
  
• Support for logging both "Referer:" and "User-Agent:" information in separate logs.
  
• Support for Aliases - to allow controlled access to file areas outside the primary document tree
  
• Support Forms with external scripts
  
  • CGI/1.1 compatible, including the 'POST' method!
  • Support for multiple CGI directories.
• Support for Basic authentication, by directory. User & group support, also.
  
• IDENT-based authentication for selected directories
• Ability to control access to selected directories to a set of machines, users, or domains. (Uses the IDENT authentication subsystem...)
• Support for specification of default files to send for selected directories.
  (I.e., the ability to designate the home page for each directory; allows local override of the default index file.)
• Provides support for the URL caching function to be available with GoServe v2.11+!

  New in v2.01.8...

• A "Moved Resource" database & automatic redirection system.
• Incorporated Mike Cowlishaw's Remote Server Control subsystem - provides remote management capabilities.
• A Load Balancing system for use with multiple server processes
• CGI scripts no-longer require the extension as part of the URL
• Support for directory requests of "/path" in addition to "/path/"

  New in v2.01.9-M...

• Incorporated several of Albert Crosby's modifications:
  • Albert's Dynamic Directory List function
  • Multiple default index page names - will search using an internal list for default pages.
  • Ability to "chain" to secondary filters upon failure of primary filter to resolve request.
  • "Footer" function - adds a standard footer to HTML documents.
  • "Special" function for executing local commands and passing back results.
• Incorporated Mike Cowlishaw's Server-Side Includes system as a module. This module can be easily replaced with a module which supports NCSA-style server-side includes. (When someone manages to write the module, that is... )
• Added support for Mike's DoPush() sample Server-push demonstration.
• Made PARSEALIASES() recursive
• Various fixes, especially to CGI & Imagemap code.

Limitations of the system:

Speed / Performance of the CGI support.

The biggest limitation of the system is the speed/performance of the CGI support -- due to the overhead involved in acquiring separate environments for each external process, the speed of completion of a CGI request is not nearly as fast as the integrated imagemap processing or normal file services. Expect CGI requests to take better than 1 second to complete -- on my 486DX33, it averaged just over 2 seconds per request.

Now a caveat upon my own caveat: After further testing, I find that my OS2HTTPD server process on the same machine is actually returning responses for the very same script with an average delay of just over 3 seconds per request. It may be that the GoHTTP code might actually be a bit faster, but further testing is definitely needed... [DLM, 16 May]

In addition to speed, the asynchronous nature of the CGI (it pipes script output to temporary files...) prevents correct operation of CGI scripts that employ what is called Server-Push, or multipart segmented documents. The multipart, segmented documents will be successfully transmitted -- all at the same time, which defeats the intent of Server-Push.

A solution to this is has been developed, and is currently in testing. Early results show that the method which allows Server-Push is approximately 40% slower than the existing method, therefore work will have to be done to optimize performance. This may mean defining a special CGI directory for those CGI programs requiring the special treatment...

Proxy support

The current filter does not support proxy requests. Several individuals are working on a solution, hopefully one will come up with something that can be rolled into the filter.

Under Development...

• Better documentation / instructions...
• Further improving speed of several functions.
• Making the CGI subsystem Server-Push capable.
• Making the CGI subsystem sensitive to subdirectories within the CGI directories.
• Improving server-side includes - Possibly creating an NCSA compatible includes module...
• I may take a stab at proxy support on my own, although it will be non-caching if anything at all...