document page 6 - Dave's Blog

OpenSearchDescriptionToHTML Tool

I've made an OpenSearchDescriptionToHTML XSLT that given an OpenSearch description file produces HTML that describes that file, lets you install it, or search with it. For example, here's a Google OpenSearch description that uses my OpenSearchDescriptionToHTML XSLT.

I had just created an OpenSearch description for WolframAlpha at work and was going about the process of adding another install link to my search provider page so that I could install it. Thinking about it, I realized I could apply an XSLT to the OpenSearch description XML to produce the HTML automatically so I wouldn't have to modify additional documents everytime I create and want to install a new OpenSearch description. While I was in there writing the XSLT I figure why not let the user try out searching with the OpenSearch description file too. And lastly I made the XSLT apply to itself to produce HTML describing its own usage.

Incidentally, I added WolframAlpha at work to replace my FileInfo search provider for the purposes of searching for information about particular Unicode characters. For instance, look at WolframAlpha's lovely output for this search for "Bopomofo zh".

Netflix CSRF - Stolen Thoughts

Looking at the HTTP traffic of Netflix under Fiddler I could see the HTTP request that added a movie to my queue and didn't see anything obvious that would prevent a CSRF. Sure enough its pretty easy to create a page that, if the user has set Netflix to auto-login, will add movies to the user's queue without their knowledge. I thought this was pretty neat, because I could finally get people to watch Primer. However, when I searched for Netflix CSRF I found that this issue has been known and reported to Netflix since 2006. Again my thoughts stolen from me and the theif doesn't even have the common decency to let me have the thought first!

With this issue known for nearly three years its hard to continue calling it an issue. Really they should just document it in their API docs and be done with it. Who knows what Netflix based web sites and services they'll break if they try to change this behavior? For instance, follow this link to add my Netflix recommended movies to your queue.

Netflix Watch Instantly Recommendations

Netflix lets you watch a subset of their movies online via their website and a subset of those movies are available to watch on the Xbox 360's Netflix app. so its not always easy to find movies to watch on Xbox 360. Yet, I regularly see my Xbox friends using the Netflix app and its a shame they didn't make an easy way to share movie recommendations with your friends. Instead we must share movie recommendations the old fashioned way. Here's the movies I've found and enjoyed on my 360.

Weeds

You don't have to be a stoner to enjoy this humorous and dramatic satire featuring a widow trying to raise her children and deal pot in suburbia.

Avatar The Last Airbender

An American animated series that's an amalgamation of various Asian art, history, religion, etc. that maintains a great story line.

Paprika

If you enjoyed Paranoia Agent you'll enjoy this movie in the same animation style and by the same director and writer, Satoshi Kon. Its like a feature length version of a Paranoia Agent episode in which a dream machine lets outsiders view one's dreams but eventually leads to blurring the dreams and reality.

Grindhouse Planet Terror

I didn't see either of the Grindhouse movies when they first came out, but of the two, Planet Terror is the more humorous and exciting gore filled parody.

Outsourced

A refreshing romantic comedy that still has a few of the over played tropes but is easy to enjoy despite that.

The King of Kong

A hilarious documentary on the struggle between the reigning champ hot-sauce salesman and the underdog Washington state high school science teacher to obtain the Donkey Kong world record high score. After watching, checkout this interview with the creators of the movie and the villain.

Primer

I've mentioned Primer before, but I put it on here again because its really good and you still haven't seen it, have you?

Outline View Internet Explorer Extension

I've made another extension for IE8, Outline View, which gives you a side bar in IE that displays an outline of the current page and lets you make intrapage bookmarks.

The outline is generated based on the heading tags in the document (e.g. h1, h2, etc), kind of like what W3C's Semantic data extractor tool displays for an outline. So if the page doesn't use heading tags the way the HTML spec intended or just sticks img tags in them, then the outline doesn't look so hot. On a page that does use headings as intended though it looks really good. For instance a section from the HTML 4 spec shows up quite nicely and I find its actually useful to be able to jump around to the different sections. Actually, I've been surprised going to various blogs how well the outline view is actually working -- I thought a lot more webdevs would be abusing their heading tags.

I've also added intrapage bookmarks. When you make a text selection and clear it, that selected text is added as a temporary intrapage bookmark which shows up in the correct place in the outline. You can navigate to the bookmark or right click to make it permanent. Right now I'm storing the permanent intrapage bookmarks in IE8's new per-domain DOM storage because I wanted to avoid writing code to synchronize a cross process store of bookmarks, it allowed me to play with the DOM storage a bit, and the bookmarks will get cleared appropriately when the user clears their history via the control panel.

Notes on Creating Internet Explorer Extensions in C++ and COM

Working on Internet Explorer extensions in C++ & COM, I had to relearn or rediscover how to do several totally basic and important things. To save myself and possibly others trouble in the future, here's some pertinent links and tips.

First you must choose your IE extensibility point. Here's a very short list of the few I've used:

• Explorer Bars and IE Toolbars
• IE Tools, IE Help, and IE Context Menu menu items
• IE Toolbar Buttons

Once you've created your COM object that implements IObjectWithSite and whatever other interfaces your extensibility point requires as described in the above links you'll see your SetSite method get called by IE. You might want to know how to get the top level browser object from the IUnknown site object passed in via that method.

After that you may also want to listen for some events from the browser. To do this you'll need to:

1. Implement the dispinterface that has the event you want. For instance DWebBrowserEvents2, or HTMLDocumentEvents, or HTMLWindowEvents2. You'll have to search around in that area of the documentation to find the event you're looking for.
2. Register for events using AtlAdvise. The object you need to subscribe to depends on the events you want. For example, DWebBrowserEvents2 come from the webbrowser object, HTMLDocumentEvents come from the document object assuming its an HTML document (I obtained via get_Document method on the webbrowser), and HTMLWindowEvents2 come from the window object (which oddly I obtained via calling the get_script method on the document object). Note that depending on when your SetSite method is called the document may not exist yet. For my extension I signed up for browser events immediately and then listened for events like NavigateComplete before signing up for document and window events.
3. Implement IDispatch. The Invoke method will get called with event notifications from the dispinterfaces you sign up for in AtlAdvise. Implementing Invoke manually is a slight pain as all the parameters come in as VARIANTs and are in reverse order. There's some ATL macros that may make this easier but I didn't bother.
4. Call AtlUnadvise at some point -- at the latest when SetSite is called again and your site object changes.

If you want to check if an IHTMLElement is not visible on screen due how the page is scrolled, try comparing the Body or Document Element's client height and width, which appears to be the dimensions of the visible document area, to the element's bounding client rect which appears to be its position relative to the upper left corner of the visible document area. I've found this to be working for me so far, but I'm not positive that frames, iframes, zooming, editable document areas, etc won't mess this up.

Be sure to use pointers you get from the IWebBrowser/IHTMLDocument/etc. only on the thread on which you obtained the pointer or correctly marshal the pointers to other threads to avoid weird crashes and hangs.

Obtaining the HTML document of a subframe is slightly more complicated then you might hope. On the other hand this might be resolved by the new to IE8 method IHTMLFrameElement3::get_contentDocument

Check out Eric's IE blog post on IE extensibility which has some great links on this topic as well.

Text/Plain Fragment Bookmarklet

The text/plain fragment documented in RFC 5147 and described on Erik Wilde's blog struck my interest and, like the XML fragment, I wanted to see if I could implement this in IE. In this case there's no XSLT for me to edit so, like my plain/text word wrap bookmarklet I've implemented it as a bookmarklet. This is only a partial implementation as it doesn't implement the integrity checks.

Check out my text/plain fragment bookmarklet.