The Boston Diaries

The ongoing saga of a programmer who doesn't live in Boston, nor does he even like Boston, but yet named his weblog/journal “The Boston Diaries.”

Go figure.

Monday, November 28, 2011

I haven't dont a metablog post in a while …

In addition to updating the greylist daemon, I've also updated the software that runs this blog.

The biggest change this time is to the configuration file. The first stab at changing how it works was made back in (let me check … oh wow! was it that long ago?) September of 2010. Prior, I had code that checked the SCRIPT_FILENAME environment variable (passed in by Apache) and changed the extention from .cgi to .cnf to locate the file. That meant the configuration file had to live in the main web directory and frankly, I felt that bit of code was always a bit of a hack.

I changed that, however, by configuring Apache to pass the configuration filename explicitly to the script:

  # ... 

  <Files boston.cgi>
        SetEnv  BLOG_CONFIG /home/spc/web/sites/

  # ...

Now, no more hacking around with filenames, and the configuration file no longer needs to be stored in a web-facing location. If you do use this method, you'll need to check REDIRECT_BLOG_CONFIG as well (which Apache sets when it does a redirect, and only a redirect).

And that was it for the configuration file until earlier this month. The next big change is how it looks. Prior to the changes this month, the configuration file looked like:

Comment:        *********************************************
Comment:        *
Comment:        *       Configure File for the Boston Diaries
Comment:        *
Comment:        **********************************************
Name:			The Boston Diaries
Backend:		/home/spc/source/boston.old.1.9/sbg/bp
BaseDir:		/home/spc/web/sites/
WebDir:         	/home/spc/web/sites/
BaseUrl:        	/
Templates:      	html/regular
DayPage:		/home/spc/web/sites/
Days:           	7
RssFile:        	/home/spc/web/sites/
RssTemplates:   	rss
RssFirst:		latest
AtomFile:		/home/spc/web/sites/
AtomTemplates:		atom
Comment: TabTemplates:	html/sidebar
Comment: TabFile:	/home/spc/web/sites/
Comment: TabFirst:	latest
StartDate:      	1999/12/4
Author:         	Sean Conner
Comment: Authors:	/home/spc/web/sites/
Email-List:		/home/spc/web/sites/
Email-Message:		/home/spc/web/sites/
Email-Subject:		The Boston Diaries Update Notification
Facebook-User:		XXXXXX
_System-CPU:		600
_System-Mem:		20971520
_System-Core:		0
_System-Locale:		en_SPC

Let me explain how this came about. I had code to parse RFC-822 style headers (because at the time I had code to fetch pages via HTTP and it's needed there; also, I can accept entries via email and I need it there too) and instead of writing even more code to parse a configuration file, I decided to shoehorn the configuration file into an RFC-822 format.

And thus, the odd format for the configuration file. It's also never been fully clensed of old features (I no longer have a backend, so the Backend: header could go; I removed support for the tab template, so TabTemplates:, TabFile: and TabFirst: could go as well—don't bother asking what the tab file was for, it'll take too long to explain and as far as I know, nobody, including myself, ever bother using it).

Even since I started playing around with Lua, I've been playing around with the idea of using it as a configuration file, and I finally got around to doing it.

process = require("org.conman.process")
os      = require("os")

-- ---------------------------------------------------------------------
-- Custom locale to get "Debtember" without special code in the program
-- ---------------------------------------------------------------------


-- --------------------------------------------------------------------
-- process limits added because an earlier version of the code actually
-- crashed the server it was running on, due to resource exhaustion.
-- --------------------------------------------------------------------

process.limits.hard.cpu  = "10m"	-- 10 minutes
process.limits.hard.core =  0		-- no core file = "20m"	-- 20 MB

-- --------------------------------------------------------
-- We now resume our regularly scheduled config file
-- --------------------------------------------------------

name      = "The Boston Diaries"
basedir   = "/home/spc/web/sites/"
webdir    = "/home/spc/web/sites/"
url       = ""
author    = { name = "Sean Conner" , email = "" }
startdate = "1999/12/4"

templates =
    template = "html/regular",
    output   = webdir .. "/index.html",
    items    = "7days",
    reverse  = true
    template = "rss",
    output   = webdir .. "/bostondiaries.rss",
    items    = 15,
    reverse  = true
    template = "atom",
    output   = webdir .. "/index.atom",
    items    = 15,
    reverse  = true

email =
  list    = "/home/spc/web/sites/",
  message = "/home/spc/web/sites/",
  subject = name .. " Update Notification",

facebook =
  ap_id     = "XXXXXXXXXXXXXXX",
  user      = "XXXXXX"

affiliate =
    proto = "asin",
    link  = ""

Not only does it look much nicer (Whitespace! Real comments!) but I was able to remove code to handle the resource limits (it's now handled in Lua—and I'll talk about that in another entry) and locales (which supports a feature I added back in October 2003).

Also, by doing this, I partially cleaned up the template mess. Before, I had to explicitely add code to support specialized templates (the HTML output, the RSS and ATOM feed files and the long-since-removed tab file); now, I can specify new templates by just adding them to the configuration file. The only limitation is that the HTML template has to be specified first (it's easier to code that way).

You'll also notice a section labeled affiliate. That I threw in at the last moment. I'm an Amazon affiliate and if I wanted to link to, say, a book from my friend Hoade, I would have to manually generate the link, but now, I can just do:

<a class="book" href="asin:0595095291">Ain't that America</a>

and it'll be converted automatically to the correct link:

<a class="book"
that America</a>

Or rather, Hoade's book Ain't that America.

On the down side, in trying to release this (the last releast was in September of 2009, and before that, July of 2004) I found a rather curious bug—below a certain threshhold of entries (and there're currently over 3,700 here in this blog), the program crashes. There's probably an assumption built into the code about there always being a previous entry, but for a new blog, that's not necessarily the case and in tracking down the issue, I found that it appears to have something to do with the internal caching I do of entries. Like the old joke goes:

There are only two hard problems in Computer Science: cache invalidation, naming things, and off-by-one errors.

And I think I'm being hit by one of—
Core error - bus dumped

Obligatory Picture

[“Only the highest fidelity images are used for identification purposes!”

Obligatory Links

Obligatory Miscellaneous

You have my permission to link freely to any entry here. Go ahead, I won't bite. I promise.

The dates are the permanent links to that day's entries (or entry, if there is only one entry). The titles are the permanent links to that entry only. The format for the links are simple: Start with the base link for this site:, then add the date you are interested in, say 2000/08/01, so that would make the final URL:

You can also specify the entire month by leaving off the day portion. You can even select an arbitrary portion of time.

You may also note subtle shading of the links and that's intentional: the “closer” the link is (relative to the page) the “brighter” it appears. It's an experiment in using color shading to denote the distance a link is from here. If you don't notice it, don't worry; it's not all that important.

It is assumed that every brand name, slogan, corporate name, symbol, design element, et cetera mentioned in these pages is a protected and/or trademarked entity, the sole property of its owner(s), and acknowledgement of this status is implied.

Copyright © 1999-2018 by Sean Conner. All Rights Reserved.