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

In addition to updating [1] the greylist daemon [2], I've also updated the software that runs this blog [3].

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 [4]) 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:

>
```
<VirtualHost 66.252.224.242:80>
# ...
<Files boston.cgi>
SetEnv BLOG_CONFIG /home/spc/web/sites/boston.conman.org/journal/boston.cnf
</Files>
# ...
</VirtualHost>
```

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: *
Comment: * Configure File for the Boston Diaries
Comment: *
Comment: **********************************************
Comment:
Name: The Boston Diaries
Backend: /home/spc/source/boston.old.1.9/sbg/bp
BaseDir: /home/spc/web/sites/boston.conman.org/journal
WebDir: /home/spc/web/sites/boston.conman.org/htdocs/
BaseUrl: /
FullBaseUrl: http://boston.conman.org
Templates: html/regular
DayPage: /home/spc/web/sites/boston.conman.org/htdocs/index.html
Days: 7
RssFile: /home/spc/web/sites/boston.conman.org/htdocs/bostondiaries.rss
RssTemplates: rss
RssFirst: latest
AtomFile: /home/spc/web/sites/boston.conman.org/htdocs/index.atom
AtomTemplates: atom
Comment: TabTemplates: html/sidebar
Comment: TabFile: /home/spc/web/sites/boston.conman.org/htdocs/boston.tab.html
Comment: TabFirst: latest
StartDate: 1999/12/4
Author: Sean Conner
Comment: Authors: /home/spc/web/sites/boston.conman.org/users
Email: sean@conman.org
Email-List: /home/spc/web/sites/boston.conman.org/notify/db/email
Email-Message: /home/spc/web/sites/boston.conman.org/notify/mail/notify
Email-Subject: The Boston Diaries Update Notification
Facebook-AP-ID: XXXXXXXXXXXXXXX
Facebook-AP-Secret: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
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 [5] style headers (because at the time I had code to fetch pages via HTTP (HyperText Transport Protocol) 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 [6] with Lua [7], 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
-- ---------------------------------------------------------------------
os.setlocale("en_SPC")
-- --------------------------------------------------------------------
-- 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
process.limits.hard.data = "20m" -- 20 MB
-- --------------------------------------------------------
-- We now resume our regularly scheduled config file
-- --------------------------------------------------------
name = "The Boston Diaries"
basedir = "/home/spc/web/sites/boston.conman.org/journal"
webdir = "/home/spc/web/sites/boston.conman.org/htdocs"
url = "http://boston.conman.org/"
author = { name = "Sean Conner" , email = "sean@conman.org" }
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/boston.conman.org/notify/db/email",
message = "/home/spc/web/sites/boston.conman.org/notify/mail/notify",
subject = name .. " Update Notification",
}
facebook =
{
ap_id = "XXXXXXXXXXXXXXX",
ap_secret = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
user = "XXXXXX"
}
affiliate =
{
{
proto = "asin",
link = "http://www.amazon.com/exec/obidos/ASIN/%s/conmanlaborat-20"
}
}
```

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 [8]).

Also, by doing this, I partially cleaned up the template mess. Before, I had to explicitely add code to support specialized templates (the HTML (HyperText Markup Language) output, the RSS [9] and ATOM [10] 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 [11] 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"
href="http://www.amazon.com/exec/obidos/ASIN/http://www.amazon.com/exec/obidos/ASIN/0595095291/conmanlaborat-20">Ain't
that America</a>
```

Or rather, Hoade's book Ain't that America [12].

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

[1] /boston/2011/11/27.1

[2] http://www.x-grey.com/

[3] https://boston.conman.org/

[4] http://httpd.apache.org/

[5] http://www.ietf.org/rfc/rfc822.txt

[6] /boston/2009/10/14.3

[7] http://www.lua.org/

[8] /boston/2003/10/23.1

[9] http://en.wikipedia.org/wiki/RSS

[10] http://en.wikipedia.org/wiki/Atom_(standard)

[11] http://www.amazon.com/

[12] https://www.amazon.com/exec/obidos/ASIN/0595095291/conmanlaborat-20

Gemini Mention this post

Contact the author