Zero to One-Eighty » wordpress

New, new, new, all-new

Adrian Cooke — Fri, 01 Jan 2010 21:08:11 +0000

Everything is new! Greywater 4 WordPress theme.

One has created version 4.0 of the not-so-venerable “Greywater” WordPress theme. New layout, new feeds from external sites, FF Meta, more hubris, white background, search is back… and I even removed the border on the header image (thanks Lyds)!

Need to figure out what to do about images in the new default column width. For CSS nerds the layout is my own, largely untested version of “liquid-elastic”—it shrinks or expands to fill the screen up (or down) to a point. Works okay on Safari (Mac, iPhone), Firefox and Camino. No idea yet how it looks on PCs. I will go ahead and assume that it’s pretty much a disaster on Internet Explorer right now. Plenty to fix and fuss with, ad nauseam, over the coming weeks…

Oh, and um… happy new year!

Embedded image metadata in WordPress

Adrian Cooke — Tue, 20 Oct 2009 03:44:33 +0000

James Duncan Davidson has written a few times (April, 2008 and January, 2009) on the problem of Flickr’s approach to embedded image metadata such as Exif (technical metadata) and IPTC and XMP (content metadata)—it’s stripped from all versions save the original uploaded image. This is not only the default behaviour—there’s no option to control this, it’s one of the conditions of using Flickr. (My guess is that this is a pragmatic decision about what users want—i.e. most don’t care—versus Yahoo!’s bandwidth costs, rather than the price of storing this information.)

It turns out that the same behaviour applies to current versions of the WordPress image resizer. This means that if you use WordPress’s native media support to display images for which copyright metadata is important, be aware that you might be serving up “orphaned” content, whose author cannot be determined when the asset is separated from your page, if you’re using the dynamically created thumbnails on your site. It looks like this might be changed in an upcoming release, but the details are hazy… The workaround is to size images yourself, output them with intact metadata, and insert them as “full size” into your posts or galleries.

New WordPress worm

Adrian Cooke — Sat, 05 Sep 2009 23:15:11 +0000

This is a bummer, man. WordPress is being targeted by a nasty worm, and it’s gaining momentum, apparently. Versions 2.8.3 and earlier are currently vulnerable. Matt Mullenweg, today, addressing the exploit:

Right now there is a worm making its way around old, unpatched versions of WordPress. This particular worm, like many before it, is clever: it registers a user, uses a security bug (fixed earlier in the year) to allow evaluated code to be executed through the permalink structure, makes itself an admin, then uses JavaScript to hide itself when you look at users page, attempts to clean up after itself, then goes quiet so you never notice while it inserts hidden spam and malware into your old posts.

It should be noted that version 2.8.4—the latest stable and secure version—is only 24 days old, so if you haven’t upgraded recently your blog is vulnerable. Apparently it’s more difficult to recover from this one than previous WordPress attacks because the worm makes changes to the database. Immediately upgrading to version 2.8.4 and making sure you have a strong password is the recommended preventive medicine. And I would add: institute a good backup routine, if you haven’t already.^† If you can get into the habit of upgrading within a week of a new release you should be able to stay ahead of these kinds of exploits.

† For example, I run a copy of my weblog on localhost using MAMP. When backing up I export the database from the remote host and import it to the local instance, check that it is displaying as it should, and confirm that I can login. I also synchronise the WordPress files using Transmit over SFTP. At least once a week—that’s my estimate of how much I could afford to lose and not start smashing things.

Renaming files, redirecting visitors

Adrian Cooke — Mon, 13 Jul 2009 03:24:40 +0000

I changed a lot of my site’s image names and locations when I switched to the new domain, breaking their file paths. So even after I had set up my global redirect on the old domain there were still a lot of 404s (file not found errors) because even though the requests got from zero2180.net to ztoe.net the rest of the path was different. (And in some cases the original images were gone for good.) A few things were helpful in cleaning up this mess.

Batch renaming files

I wanted to change the names of my main images, like harvey001.jpg, to remove the word “harvey”, 001.jpg, etc. One way to do this is with a batch operation using for, mv and regular expressions, like so:

for f in harvey* ; do mv "$f" "${f#harvey}" ; done

This loops through the files in the current directory that match “harvey-something,” and moves them so that the matched phrase is not replaced with anything. For thumbnails I wanted to rename them with the word “thumb,” thus:

for f in harvey* ; do mv "$f" "thumb${f#harvey}" ; done

This time the matched string to be removed is preceded by a new string, “thumb” (# matches the beginning of the filename and % matches the end).

Permanent Redirects and RedirectMatch

Because I renamed the files and moved them as well I needed a way to redirect (using mod_alias) requests for each image. In some cases it was easiest to use Redirect permanent, where there was a clear one-to-one change, and in others RedirectMatch permanent, where I wanted to apply a pattern match to a set of files.

There’s probably a better way to do this, but this is what I used:

Redirect permanent /photos/0304/harvey http://ztoe.net/photos/harvey
RedirectMatch permanent images/harvey(.*)\.jpg$ 

http://ztoe.net/photos/harvey/$1.jpg

RedirectMatch permanent thumbs/harvey(.*)\.jpg$

http://ztoe.net/photos/harvey/thumb$1.jpg

The first line redirects everything requested via the first string to the URL at the end of the line. It works recursively so anything more specific than /photos/0304/harvey is also redirected. The second and third lines match any of the images in /photos/0304/harvey/images (called, for example, harvey001.jpg in both directories) and /photos/0304/harvey/thumbs respectively, and send them to the right place on the new domain, with the correct filename (e.g. 001.jpg and thumb001.jpg).

Telling visitors that something is gone

Where images are gone for good, because I want it that way, sending a 404 can mean that Google, et al. will continue spidering the dead URL for a long time. This is because HTTP error 404 is a catch-all that means the resource is not here, but doesn’t attempt to say anything in particular about that.

To indicate that a resource is permanently gone, with no forwarding address, the correct code is error 410 Gone:

Redirect gone /old/path/to/image.jpg

You can use an ErrorDocument directive to make the resulting message more palatable. I haven’t done this yet because I’d like to see if I can get WordPress to handle 410s while sending the correct header response to the client. (I’m aware of the Ask Apache plugin, but not pysched about the Google Search API Key requirement.)

A better 404 page

For WordPress users the 404 codex page is required reading. Apparently, it was only in recent versions that WordPress began to send 404 header responses when it served a 404 page (meaning that humans might know a file was “not found” but servers didn’t). Less than ideal.

If you want to be notified whenever a client follows a link to your WordPress site that results in the 404 error page, then add the script in the “Writing Friendly Messages” section to your 404.php file. It tells the user what URL they requested that caused the 404, but it also e-mails the site administrator when the referrer variable is set (meaning that your visitor clicked on a link that brought them to the non-existent resource).

Afterthought

I use analytics software on my site, but I rarely inspect the raw server logs. The number of 404s I found in the log files recently was surprising, especially since I learned that 404s don’t necessarily result in web crawlers learning that the resource is never coming back. If you don’t set a forwarding address for resource requests or indicate that the resources is gone, the “mail” keeps coming—and I guess that makes your site look as though nobody’s home.

New domain

Adrian Cooke — Sat, 04 Jul 2009 16:03:24 +0000

This weekend I moved Zero to One-Eighty to a new domain name. You should be redirected automatically, but please update any bookmarks and feeds. The old domain is zero2180.net. The new domain is ztoe.net. The new feed is at ztoe.net/feed/atom. Sorry if this change causes your feed reader to barf up duplicates of the last twenty or so posts. It did in mine.

Technicalities

For anyone interested in the nerd story, here are some notes.

When I first registered zero2180.net back in 2005 I wanted something fairly short, but I was never happy with it because the meaning was unclear and it was hard to verbalise (“z, e, r, o—the letter, 2, 1, 8, 0—the number” ugh… just delightful to have to say all this over the phone, way to go Mr. Usability).
I also had all kinds of parts to the site back then—the portfolio was called “Pixel Rebellion,” (zero2180.net/pixelrebellion) the photos were called “Longitudes,” (zero2180.net/longitudes) the blog was “Dead Reckoning” (zero2180.net/deadreckoning) and the URLs, well: http://www.zero2180.net/deadreckoning/2007/03/02/they-came-from-the-north/. I changed most of this a while back, and the new domain fixes the last problem.
Late last year, when I registered ztoe.net, I stopped being a tightwad for five seconds, did it right and went with a good registrar.
When I set up the new domain on my shared hosting account I created a new location for it on the server, and used Subversion to install the latest version of WordPress (2.8), which takes, like, two seconds, seriously.
The tricky part was updating the site URL in my database. The afore-linked instructions are great, based as they are on the original (and best) Podz guide. I wound up having to find and replace the URL in more places than are specifically mentioned here, but the section on “changing the URL directly in the database” was the place to start, of course only after making copious backups.
I had some problems with wp-cache at first that had me stumped for a while (the server kept spewing encoding errors). Deleting and reinstalling the plugin from within WordPress did the trick nicely.
Since then I’ve been spending most of my time fixing images in posts, because I originally had them in a separate assets folder back in the days of WordPress 1.5, but then the media gallery came along, etc. One nice (newish?) feature is that if you have enabled the option to place uploads in time-based folders and you add an image to an old post, it creates folders for the resource based on the post’s publication date rather than the current date.

I’m still working on fixing all of the images, but if you notice any 404s or other glitches that don’t seem right, please let me know.

Update: see the Changes page for additional information.

Faster

Adrian Cooke — Sun, 22 Mar 2009 09:42:52 +0000

I ran around in the yard with my dog today, partly to remind myself how perfectly in shape I’m not, but mainly because she thought it was the best fun ever, and she draws a lot of water around here. Then the temperature dropped, I came inside, and parked in front of my computer. Father of the year? You bet.

This post is actually about things I’ve done (that have worked) to speed up WordPress 2.7 on shared hosting:

Output compression: compresses the text transferred (HTML, stylesheets, scripts, etc.) for browsers that indicate they can handle it. For example:


AddOutputFilterByType DEFLATE text/plain
AddOutputFilterByType DEFLATE text/html
AddOutputFilterByType DEFLATE text/xml
AddOutputFilterByType DEFLATE text/css
AddOutputFilterByType DEFLATE application/xml
AddOutputFilterByType DEFLATE application/xhtml+xml
AddOutputFilterByType DEFLATE application/rss+xml
AddOutputFilterByType DEFLATE application/javascript
AddOutputFilterByType DEFLATE application/x-javascript
AddOutputFilterByType DEFLATE application/x-httpd-php
AddOutputFilterByType DEFLATE application/x-httpd-fastphp

Expires headers: sends the browser an expiration date for some assets like stylesheets and images so it won’t try to fetch them again until that date is reached. Stylesheets have timestamps appended (e.g. style.css?1237154177) when they change, effectively changing the filename and forcing them to be updated. For example:
```
ExpiresActive On
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType text/css "access plus 10 years"
```
WP Cache 2: a plugin that reduces the amount of server-side code execution and database queries required to serve a page, by caching them as static files
Simple markup: lean, semantic markup using the HTML5 doctype and as little extraneous cruft as possible
Simple styles and behaviours: using only one external CSS and one external JavaScript file, both modest in size

Yahoo!’s YSlow plugin for Firefox and the associated rules helped a lot with the first two things, and Andrew King’s website optimization analyser with general performance testing. More recently I discovered Alex Shiels’ Is My Blog Working—it’s a nice tool though it seems to draw different conclusions as my server’s response time fluctuates.

So that’s that. Citius, altius, fortius, because, as everyone knows: Internet is serious business.

Grids

Adrian Cooke — Sun, 22 Feb 2009 04:47:37 +0000

Layout of F8 Lite by Thad Allender, used to dramatic effect by Jonathan Jarvis

Believe it or not I used a grid tool when I made the most recent layout for this site. I can’t remember how I found ctrl+shift+g, but it’s surprisingly useful for aligning elements on the page, even if said page includes (ahem) one column. It’s a JavaScript implementation of Khoi Vinh’s clever background image technique.

More recently I came across The Grid System, with it’s complex and highly controlled grid layout. I really like the “Show Grid” feature (top right) because it highlights horizontal as well as vertical sections. The site bills itself as “The ultimate resource in grid systems.” It’s a bold strategy, Cotton. Let’s see if it pays off for ’em. (I’m pretty sure I won’t have to star any others.)

WordPress Automatic Update

Adrian Cooke — Sat, 14 Feb 2009 04:57:07 +0000

After years of following the extended upgrade instructions for WordPress I was a little skeptical about using the “automatic update” feature in 2.7. But it’s a nice implementation that requires fewer steps and worked smoothly for me.

Before you start, you should back up your database, and verify that the backup works. I also redirect traffic to a “down for maintenance” message while I’m upgrading. (It’s probably best to disable plugins too.) Then, run Automatic Update:

This beats waiting around for SFTP

The main difference is the speed of the actual update. It ran in a minute or so. The rest of the time was spent synchronising remote files to the local machine, rather than the other way around. The whole process probably takes about the same amount of time as updating via SVN, but this option will be a lot easier for users who are more comfortable with a GUI than the command line.

This is probably the best new feature in WordPress.

The redesign of drupal.org

Adrian Cooke — Thu, 01 Jan 2009 20:02:40 +0000

@drupalredesign’s latest prototype update on Twitter

Mark Boulton and co are redesigning drupal.org using a “community design” process similar to the one that Automattic is using with WordPress these days. I was skeptical about this at first, though the interface redesign in WordPress 2.7 came out pretty well, more horse than camel. Both groups seem to be making this approach work.

For the Drupal redesign Boulton’s team is being really systematic about it: they released a new design prototype every Thursday through October and November so that people could comment over the weekend through various feedback channels (mainly Drupal Groups, but also Flickr and Twitter). Boulton comments that:

Through the flaming, disagreements, and arguments are clear, actionable points, which we take forward to the next round. At first, I thought design by community would be as bad as design by committee. Lots of people, all wanted their say, mixing black with white and ending with grey. Not so.

The results are clear and observable in the prototypes. It’s good to see how much the most recent iteration emphasises utility over exposition of the product. Earlier versions read more like an advertisement which encourages evaluation of the various claims (thinking), while later versions look more like something you can get down and use, which encourages interaction and exploration (doing).

Quirky permalinks problem

Adrian Cooke — Sun, 09 Nov 2008 09:58:35 +0000

A short while ago I noticed that a few posts were suddenly returning a 404 and the standard Apache warning for no apparent reason (WordPress 2.6.3). At first I thought it was just one, but I eventually discovered two others, with no obvious pattern among them. I searched the forums and but didn’t find any reports that quite matched mine. Turns out the fix was to change the permalink setting back to the “default” option (in Settings → Permalinks), and then re-select the one I use, “month and name.” These threads contain suggestions for this: switching to default and then back to custom, though here the problem seemed to be affecting all posts.