Programming Assignment - Graphing with GD::Graph

In this assignment, you will use the GD::Graph module to create a bar chart that shows web usage for evc-cit.info.

You will use a form like this to let the user choose a day (the year is fixed at 2005), and then produce a page that gives both a table of accesses by hour as well as a graph of the accesses. The example form is active; you may try it and see it in action.

You will not be using the real log file; you will be using a copy of it that will be updated every day. The file you will want to analyze is /var/log/access_copy. This solves a lot of problems with reading a file that is open and being updated by another process. Make sure you close the file when you finish reading it!

I have not told you anything about what the log file looks like internally; you have to find that out for yourself.

You must write two scripts. The first one, which must be named stats.cgi will produce the table of statistics and an <img> element whose src attribute is a call to the second script, which must be named graphstats.cgi.

Hints, etc.

• You may choose any color scheme you like for your chart.
• If you want horizontal bars instead of vertical bars, go for it.
• Here is the documentation for GD and GD::Graph. You may also download a zip file containing the documentation for local use.
• You may also download all the sample files for GD::Graph or download them individually.
• The log file is consistent. That is, entries always appear in chronological order, and the general format of each entry is always the same.
• If you use pattern matching (and it would be a good idea), keep your patterns simple. Taking apart a log entry is not brain surgery.