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Halloween and Gas Park Weekend

The weekend before last Sarah and I went down to Gas Works Park in Seattle. Gas Works Park is a former Seattle Gas Light Company gasification plant now turned into a park with the machinery kept intact and found right on the shore of Lake Union. There's a large hill right next to the plant with an embedded art installation from which you get an excellent view of the park and the lake. Anyway a very cool place. Afer, we ate at Julia's of Wallingford where I stereotypically had the Santa Cruz omelet. Good food, nice place, nice neighborhood.

This past weekend was Halloween weekend. On Halloween at Microsoft parents bring their kids around the office buildings and collect candy from those who have candy in their office. See Matt's photo of one such hallway at Microsoft. The next day Sarah and I went to two birthday parties the second of which required costume. I went as House (from the television show House) by putting on a suit jacket and carrying a cane. Sarah wore scrubs to lend cred. to my lazy costume. Oh yeah and on Sunday Sarah bought a new car.

Investigation of a Few Application Protocols (Updated)

Windows allows for application protocols in which, through the registry, you specify a URL scheme and a command line to have that URL passed to your application. Its an easy way to hook a webbrowser up to your application. Anyone can read the doc above and then walk through the registry and pick out the application protocols but just from that info you can't tell what the application expects these URLs to look like. I did a bit of research on some of the application protocols I've seen which is listed below. Good places to look for information on URI schemes: Wikipedia URI scheme, and ESW Wiki UriSchemes.

Dr. Horrible Link Roundup

New office, new cubes

My previous window office was ripped from me when our team moved buildings but now I've got another. The photo is poor because I didn't get the lighting correct and it depicts the office before I've moved all my crap into it. I have a lovely view of our parking lot and freeway which Jane spun as an 'urban view'. At any rate I'm not complaining: I like knowing what its like outside and that there is an outside. The day after I found out about my office, I also got two new patent cubes. I didn't have any pictures last time so I took some now and blacked out their text for fear of laywers.

Second Window Office

sequelguy posted a photo:

My new window office, before I took out the old furniture and moved in all of my crap. A lovely view of parking lot and freeway.

Kirkland Uncorked Weekend

Saturday we went to Kirkland Uncorked, a wine tasting festival near our home. We took the bus and after finding the correct one (they really should have different numbers for buses that are on the same route but traveling in different directions) made it to the festival. Unfortunately I don't remember any of the names of the wines just which ones I enjoyed by order. Recalling that I enjoyed the first one I had and the second to last one, doesn't really help me find them again. There were local artists who had setup booths and Sarah got a lovely necklace. After that we ate at Cactus which, because it was such a lovely day, had all its windows and doors open.

Sunday was quieter. A few household chores and plenty of GTA4. I almost got the One Man Army achievement but I found that after four minutes with six stars I eventually dropped back down to three stars without realizing it.

URI Fragment Info Roundup

Information about URI Fragments, the portion of URIs that follow the '#' at the end and that are used to navigate within a document, is scattered throughout various documents which I usually have to hunt down. Instead I'll link to them all here.

Definitions. Fragments are defined in the URI RFC which states that they're used to identify a secondary resource that is related to the primary resource identified by the URI as a subset of the primary, a view of the primary, or some other resource described by the primary. The interpretation of a fragment is based on the mime type of the primary resource. Tim Berners-Lee notes that determining fragment meaning from mime type is a problem because a single URI may contain a single fragment, however over HTTP a single URI can result in the same logical resource represented in different mime types. So there's one fragment but multiple mime types and so multiple interpretations of the one fragment. The URI RFC says that if an author has a single resource available in multiple mime types then the author must ensure that the various representations of a single resource must all resolve fragments to the same logical secondary resource. Depending on which mime types you're dealing with this is either not easy or not possible.

HTTP. In HTTP when URIs are used, the fragment is not included. The General Syntax section of the HTTP standard says it uses the definitions of 'URI-reference' (which includes the fragment), 'absoluteURI', and 'relativeURI' (which don't include the fragment) from the URI RFC. However, the 'URI-reference' term doesn't actually appear in the BNF for the protocol. Accordingly the headers like 'Request-URI', 'Content-Location', 'Location', and 'Referer' which include URIs are defined with 'absoluteURI' or 'relativeURI' and don't include the fragment. This is in keeping with the original fragment definition which says that the fragment is used as a view of the original resource and consequently only needed for resolution on the client. Additionally, the URI RFC explicitly notes that not including the fragment is a privacy feature such that page authors won't be able to stop clients from viewing whatever fragments the client chooses. This seems like an odd claim given that if the author wanted to selectively restrict access to portions of documents there are other options for them like breaking out the parts of a single resource to which the author wishes to restrict access into separate resources.

HTML. In HTML, the HTML mime type RFC defines HTML's fragment use which consists of fragments referring to elements with a corresponding 'id' attribute or one of a particular set of elements with a corresponding 'name' attribute. The HTML spec discusses fragment use additionally noting that the names and ids must be unique in the document and that they must consist of only US-ASCII characters. The ID and NAME attributes are further restricted in section 6 to only consist of alphanumerics, the hyphen, period, colon, and underscore. This is a subset of the characters allowed in the URI fragment so no encoding is discussed since technically its not needed. However, practically speaking, browsers like FireFox and Internet Explorer allow for names and ids containing characters outside of the defined set including characters that must be percent-encoded to appear in a URI fragment. The interpretation of percent-encoded characters in fragments for HTML documents is not consistent across browsers (or in some cases within the same browser) especially for the percent-encoded percent.

Text. Text/plain recently got a fragment definition that allows fragments to refer to particular lines or characters within a text document. The scheme no longer includes regular expressions, which disappointed me at first, but in retrospect is probably good idea for increasing the adoption of this fragment scheme and for avoiding the potential for ubiquitous DoS via regex. One of the authors also notes this on his blog. I look forward to the day when this scheme is widely implemented.

XML. XML has the XPointer framework to define its fragment structure as noted by the XML mime type definition. XPointer consists of a general scheme that contains subschemes that identify a subset of an XML document. Its too bad such a thing wasn't adopted for URI fragments in general to solve the problem of a single resource with multiple mime type representations. I wrote more about XPointer when I worked on hacking XPointer into IE.

SVG and MPEG. Through the Media Fragments Working Group I found a couple more fragment scheme definitions. SVG's fragment scheme is defined in the SVG documentation and looks similar to XML's. MPEG has one defined but I could only find it as an ISO document "Text of ISO/IEC FCD 21000-17 MPEG-12 FID" and not as an RFC which is a little disturbing.

AJAX. AJAX websites have used fragments as an escape hatch for two issues that I've seen. The first is getting a unique URL for versions of a page that are produced on the client by script. The fragment may be changed by script without forcing the page to reload. This goes outside the rules of the standards by using HTML fragments in a fashion not called out by the HTML spec. but it does seem to be inline with the spirit of the fragment in that it is a subview of the original resource and interpretted client side. The other hack-ier use of the fragment in AJAX is for cross domain communication. The basic idea is that different frames or windows may not communicate in normal fashions if they have different domains but they can view each other's URLs and accordingly can change their own fragments in order to send a message out to those who know where to look. IMO this is not inline with the spirit of the fragment but is rather a cool hack.

Warm Weekend

It was warm and lovely out this past Saturday and Sarah I and went to a new place for lunch, then to Kelsey Creek Park, and then out for Jane's birthday. We ate at Cafe Pirouette which serves crepes and is done up with French decorations reminding me of my parent's house. We got in for just the end of lunch and saw the second to last customers, a gaggle of older ladies leaving. I felt a little out of place with my "Longhorn [heart] RSS" t-shirt on. The food was good and in larger portions that I expected.

After that we went to Kelsey Creek Park and Farm. The park is hidden at the end of a quiet neighborhood, starts out with some tables and children's jungle gym equipment, then there's a farm which includes a petting zoo, followed by many little trails going off into the forrest. There weren't too many animals out and the ones we did see didn't seem to expect or want the sun and warm weather. We followed one of the trails for a bit and turned back before getting sun burned. You can see my weekend photos mapped out on Live Maps.

That night we went out with some friends for Jane's birthday. Eric was just back from the RSA conference and we met Jane and Eric and others at Palace Kitchen in Seattle located immediately adjascent to the monorail's route. The weather was still good so they left the large windows open through twilight and every so often you'd see the monorail pass by.

Feed Folder Deprecated; Use Internet Explorer 8

Internet Explorer 8 has made my plugin Feed Folder obselete in functionality and implementation -- which is good!

I made Feed Folder for IE7 because I wanted the Live Bookmarking feature from FireFox. The Feed Folder plugin for IE7 would allow you to display your feeds as virtual folders in your Links Bar. When your feed is updated the virtual folder is updated as well with the new feed items. I use del.icio.us to store all my links so I could add virtual folders of my daily links, my friends blogs links, quick reference links, etc. etc.

My plugin relied on shell folders to implement the virtual folders I described above, but IE8 doesn't support shell folders in the Favorites Bar. But I'm OK with Feed Folder not working in IE8 since there's a much better implementation already there. IE8 does better than my plugin on a number of points: First, there isn't the horrible perf. issue that my plugin had on Vista. Second, when a feed is updated the virtual folder flashes to note the change in status. Third, unread items are bolded and the bolding bubbles up from feeds contained in subfolders. And lastly, the middle click button is supported to open items in a new tab.

Accordingly, I don't plan to work on Feed Folder anymore unless someone comes up with a good reason. Instead I mark Feed Folder deprecated and suggest you use Internet Explorer 8 instead.

To use this feature in IE8 simply drag a feed from your feed list in your Favorites Center onto your Favorites Bar. Or, when viewing a feed, click on the 'Add to Favorites' Star Plus icon thing in the upper left, and select 'Monitor on Favorites Bar'. A .url Internet Shortcut file is produced as usual, but if you open up the .url file you'll see there's some additional info about the feed.

URI Addressable Text Adventure Games

This post is about creating a server side z-code interpreter that represents game progress in the URI. Try it with the game Lost Pig.

I enjoy working on URIs and have the mug to prove it. Along those lines I've combined thoughts on URIs with interactive fiction. I have a limited amount of experience with Inform which generates Z-Code so I'll focus on pieces written in that. Of course we can already have URIs identifying the Z-Code files themselves, but I want URIs to identify my place in a piece of interactive fiction. The proper way to do this would be to give Z-Code its own mimetype and associate with that mimetype the format of a fragment that would contain the save state of user's interactive fiction session. A user would install a browser plugin that would generate URIs containing the appropriate fragment while you play the IF piece and be able to load URIs identifying Z-Code files and load the save state that appears in the fragment.

But all of that would be a lot of work, so I made a server side version that approximates this. On the Web Frotz Interpreter page, enter the URI of a Z-Code file to start a game. Enter your commands into the input text box at the bottom and you get a new URI after every command. For example, here's the beginning of Zork. I'm running a slightly modified version of the Unix version of Frotz. Baf's Guide to the IF Archive has lists of IF games to try out.

There are two issues with this thought, the first being the security issues with running arbitrary z-code and the second is the practical URI length limit of about 2K in IE. From the Z-Code standard and the Frotz source it looks like 'save' and 'restore' are the only commands that could do anything interesting outside of the Z-Code virtual machine. As for the length-limit on URIs I'm not sure that much can be done about that. I'm using a base64 encoded copy of the compressed input stream in the URI now. Switching to the actual save state might be smaller after enough user input.