February 2018 Update: Stylesheet/template changes, described at end of article. Appropriate changes made to article body.
January 2018 Update: Some major form changes, described at end of article. Appropriate changes made to article body.
December 2017 Update: More changes, described at end of article.
October 2017 Update: I regret that I let this article get badly out of whack with reality. Notably, most of the links to my code, which were on the old UNH "pubpages" server, went stale when I retired. In addition, I've cleaned up the code some and fixed a nasty Daylight Savings Time-related bug. I hope. Further notes at the bottom of the article.
Note: this post is out of whack with normal Pun Salad content. Only recommended for:
- computer geeks who (like me) tend to approach everyday issues by asking: how could I write code to make this easier?; or
- psychologists who might be interested in whatever mental aberration causes the behavior exhibited in (a).
A few years back I noticed I was doing a miserable job of reading the magazines to which I was subscribed; the new issue would show up and I would have just read few if any articles in the previous one.
A similar problem with books: I would check them out of the library and return them unread. And my to-be-read pile of owned books just was getting bigger.
What worked for me was to set up a reading schedule for each "new" book or magazine. Simply read through a reasonable, fixed number of pages each day, until done. Lather, rinse, repeat.
I'm currently implementing this scheme by generating a calendar-format schedule for each item in HTML. Example for a book I read back in 2014, Freedom™ by Daniel Suarez:
I (1) print the schedule from my web browser, (2) cut it out, (3) attach to a card, and (4) use the result as a bookmark for the item. And each day, I try to meet the page goal for each item.
(Not that it matters, but for magazines I staple the schedule to one of the subscription cards that invariably accompany each issue. For books, I tape it to one of the plastic advertising cards the Yankee Candle company sends us, which are significantly more substantial.)
Now I'm not psycho about this: it's OK to get ahead of the goals if the material is compelling and I have the time. It's also OK to fall behind if there's just too much other stuff going on. (However, in my experience, just knowing that I've "fallen behind" is just enough self-nudging motivation to carve out some extra time to catch up later.)
Enough for the mechanics, on to the code. For a long time I ran a Perl script from a Linux command line to generate a schedule. But I realized that it would be (slightly) more flexible to set up an HTML form to get the schedule parameters, calling a CGI backend to display the result.
The form I'm using is here. (Do I have to mention that you can use your browser's source-viewing capabilities to view the HTML source? Nah, probably not.) But it looks like this [as of January 2018]:
[December 2017: removed paragraph about the jQuery datepicker, no longer used.]
The generated schedule uses a CSS stylesheet found here. No claims are made for its quality.
So you fill out the form, for example:
[Note: I urge you to try it yourself.]
… hit the submit button and the resulting page should produce the appropriate schedule. (I'm pretty sure it would work for you if you want to try it.)
The real work is performed by the
Perl CGI script, which relies heavily on the smarts contained in the
modules. If you'd like to look at that (feel free to adapt it to
your own preferences if you are so inclined):
the plaintext Perl file is
and the html-prettyprinted version is
The HTML template used by the script is also important
and that's here.
Additional notes (October 2017).
As previously mentioned, the original version of the CGI script lived on
the UNH "pubpages" webserver, where I enjoyed
rootaccess. It's now on the Pun Salad server, where I don't. This is problematic when you need to install some random CPAN perl module.
The most recent bug squashed was one I've struggled with for years: if
your timezone does DST, not all days are 24 hours: the "spring forward"
day has only 23; the "fall back" day has 25. This resulted in strange
behavior when a reading schedule traversed one of those days.
The fix turned out to be relatively easy: tell the script to pretend it's in the UTC timezone. Duh. That's accomplished by (for example) the line
$startdate->config( 'setdate', 'now,UTC' );
After years, I noticed that, in many cases, I wanted to spend a specific
number of days reading a book or magazine. This involved me looking at a
calendar, and finger-counting to figure out what end-date to specify in the form.
Duh. That's an unforgivable user interface sin, is it not?
So the input form now requests either (a) the end-date for the reading schedule, or (b) the number of days the schedule should run from the start date.
If you enter both, the end date will be ignored, but why would you do that?
The form has been otherwise (ahem) brought into the 21st century. Title,
start date, start page, and end page input fields now sport the HTML
typeattribute is used specify that the title should be
text, the start/end pages should be
number, and the start/end dates should be
That means the web browser's native date-picker UI will be used for date entry instead of the previous jQuery datepicker. (Some old browsers don't support this, but since I'm not being paid to support old browsers, I can say "gee, that's too bad", without guilt.)
page has to be less than the end page, either the number-of-days or the
end-date input has to be there, and if the end-date is specified, it has
to be after the start date.
Web Security 101 saith: your CGI must still check the validity of its
inputs. So all that code is still in the CGI. But…
I also modified the CGI script to use the Perl
Time::Piecemodule for calendar arithmetic instead of
Date::Manip. This greatly simplified the code, and (somewhat surprisingly)
Time::Pieceseems to do the right thing when the reading schedule overlaps a Daylight Saving time warp.
I still think
Date::Manipis vital for heavy-lifting Date/Time calculations. But it's overkill here.
January 2018 Update: Some minor surgery on the form. Did I say above that I had brought it into the 21st century? Not quite. My web design skills have always been weak, since that was never my job; I was pretty much a "get the content up" guy, and I only learned enough CSS to make things look the way I wanted at the time. That's the case here too. Summary:
- Rearranged the form elements so they had a more intuitive ordering.
- Switched to using an embeded stylesheet.
- Used some advanced (non-table) styles for form layout.
I think it looks prettier now.
February 2018 Update: See above about my web design skills being weak. I can't say that the most recent changes make the design "good", but I think I can claim "better".
Changed to a standalone style sheet for the generated calendar bookmark.
The bookmark used tables for layout. I hear that's been frowned upon
for, oh, the last 20 years or so. Layout now accomplished by CSS.
I changed the outer boundary of the bookmark from a dotted line to
dashes. I think that looks better.