real page 7 - Dave's Blog

Grocery Shopper Data Use

QFC, the grocery store closest to me, has those irritating shoppers cards. They try to motivate me to use it with discounts, but that just makes me want to use a card, I don't care whose card and I don't care if the data is accurate. They should let me have my data or make it useful to me so that I actually care.

I can imagine several useful tools based on this: automatic grocery lists, recipes using the food you purchased, cheaper alternatives to your purchases, other things you might like based on what you purchased, or integration with dieting websites or software. At any rate, right now all I care about is getting the discount from using a card, but if they made the data available to me then the grocery store could align our interests and I'd want to ensure the data's accuracy.

Time/Date Conversion Tool

I built timestamp.exe, a Windows command line tool to convert between computer and human readable date/time formats mostly for working on the first run wizard for IE8. We commonly write out our dates in binary form to the registry and in order to test and debug my work it became useful to be able to determine to what date the binary value of a FILETIME or SYSTEMTIME corresponded or to produce my own binary value of a FILETIME and insert it into the registry.

For instance, to convert to a binary value:

[PS C:\] timestamp -inString 2009/08/28:10:18 -outHexValue -convert filetime
2009/08/28:10:18 as FILETIME: 00 7c c8 d1 c8 27 ca 01

Converting in the other direction, if you don't know what format the bytes are in, just feed them in and timestamp will try all conversions and list only the valid ones:

[PS C:\] timestamp -inHexValue  "40 52 1c 3b"
40 52 1c 3b as FILETIME: 1601-01-01:00:01:39.171
40 52 1c 3b as Unix Time: 2001-06-05:03:30:08.000
40 52 1c 3b as DOS Time: 2009-08-28:10:18:00.000

[PS C:\] timestamp -inHexValue  "40 52 1c 3b" -convert guess
40 52 1c 3b as DOS Time: 2009-08-28:10:18:00.000

When I first wrote this I had a bug in my function that parses the date-time value string in which I could parse 2009-07-02:10:18 just fine, but I wouldn't be able to parse 2009-09-02:10:18 correctly. This was my code:

success = swscanf_s(timeString, L"%hi%*[\\/- ,]%hi%*[\\/- ,]%hi%*[\\/- ,Tt:.]%hi%*[:.]%hi%*[:.]%hi%*[:.]%hi", 
&systemTime->wYear,
&systemTime->wMonth,
&systemTime->wDay,
&systemTime->wHour,
&systemTime->wMinute,
&systemTime->wSecond,
&systemTime->wMilliseconds) > 1;

To convert between these various forms yourself read The Old New Thing date conversion article or Josh Poley's date time article. I previously wrote about date formats I like and dislike.

Creating Accelerators for Other People's Web Services

Before we shipped IE8 there were no Accelerators, so we had some fun making our own for our favorite web services. I've got a small set of tips for creating Accelerators for other people's web services. I was planning on writing this up as an IE blog post, but Jon wrote a post covering a similar area so rather than write a full and coherent blog post I'll just list a few points:

• The first thing to try is looking for developer help for the web service, specifically if there's a REST-ful URL based API. For example, Bing Maps has great URL API documentation that would be enough to create an Accelerator.
• The Accelerator XML is very similar to HTML forms. If you can find an HTML form for the web service for which you want to create an Accelerator, you can view the HTML source and create an Accelerator based on that.
• I created the FormToAccelerator extension based on the previous idea. You can use the extension to create an Accelerator from an HTML form, or just use it to create the start of one and edit it manually after.
• If the page doesn't use an HTML form, you can start up an HTTP debugger like Fiddler, use the web service from the normal web page, and then in Fiddler see if you can find a REST-ful looking URL you can use.
• When looking to create a preview for your Accelerator, see if the web page for the web service has a mobile version or a version that's intended to embed in other web pages via an iframe. On this same line, iPhone apps make great Accelerators usually with lovely previews.
• If there's no mobile or embeddable version and the only thing wrong with the normal web page for the web service is that the useful information doesn't fit in the preview window then see if you can find an HTML tag with a name or id near the useful information, and stick a '#' fragment pointing to that tag onto the preview URL template.
• Without a reasonable REST-ful API you can use a combination of Google's "site:" and "I'm Feeling Lucky" to find the most relevant page on a particular site.
• The value of a name and value pair need not consist of only a single Accelerator variable. You can get creative and put other text in there. For instance, I implemented a Google currency conversion by setting the query to "{selection} in US Dollars".

IE8 Search Providers, Accelerators, and Local Applications Hack

There's no easy way to use local applications on a PC as the result of an accelerator or a search provider in IE8 but there is a hack-y/obvious way, that I'll describe here. Both accelerators and search providers in IE8 fill in URL templates and navigate to the resulting URL when an accelerator or search provider is executed by the user. These URLs are limited in scheme to http and https but those pages may do anything any other webpage may do. If your local application has an ActiveX control you could use that, or (as I will provide examples for) if the local application has registered for an application protocol you can redirect to that URL. In any case, unfortunately this means that you must put a webpage on the Internet in order to get an accelerator or search provider to use a local application.

For examples of the app protocol case, I've created a callto accelerator that uses whatever application is registered for the callto scheme on your system, and a Windows Search search provider that opens Explorer's search with your search query. The callto accelerator navigates to my redirection page with 'callto:' followed by the selected text in the fragment and the redirection page redirects to that callto URL. In the Windows Search search provider case the same thing happens except the fragment contains 'search-ms:query=' followed by the selected text, which starts Windows Search on your system with the selected text as the query. I've looked into app protocols previously.

Dave's Blog Entries Last Year

Inspired by one of Penn's (of Penn & Teller) articles in which he mentions he has his computer tell him what he wrote in his journal that day the previous year, I've wanted to implement a similar thing with my blog. Now that, as I mentioned previously, I've updated my blog such that its much easier to implement search and such, I've added date range filtering to my site's search. So now I can easily see what on Delicious and my blog I was doing last year.

I've also otherwise updated search on this site. You can now quote terms to match an entire string, stick 'tag:' in front of a term to only match that term against tags as opposed to the title and body of the entry as well, and you can stick '-' in front of a term to indicate that it must not be found in the entry.