MikeKelly's WebLog : development

Top Ten Things at PDC 2009

MikeKelly — Fri, 20 Nov 2009 01:03:00 GMT

I’m sitting at LAX writing this summary of PDC which is just wrapped up. Although I went “on my own dime” (i.e. I paid my own way), it was definitely worth it for the ten reasons below…

Learning a bunch more about Azure storage and SQL for Azure at Jai Haridas’ session and Brad Calder’s session on blobs, queues and the just-announced xDrive – which allows an Azure page blog to be formatted and mounted as an NTFS virtual drive.
Microsoft Expression Blend’s SketchFlow, which is an amazingly easy-to-use and complete prototyping environment, described by Christian Schormann in a session marred only by his cough, which was very, very loudly amplified throughout the room until the sound guy caught on and reduced the volume when Christian turned from the audience to cough. This falls into one of those things which I have installed on my machine, booted once and never really spent the time to figure out – now I will.
A very demo-intensive and impressive session on the Bing Maps API by Keith Kinnan. I knew Virtual Earth (now Bing Maps) had an API, but I had no idea how sophisticated it is and how many very cool things can be built quite easily.
Ray Ozzie’s announcement in the Tuesday keynote of a project codenamed “Dallas” which is an ambitious attempt to provide very high-value data sources licensed under a uniform EULA and for minimal or no cost. There weren’t a lot of details on this, but stay tuned on this one – combined with the ADO.Net RESTful data services, this could be pretty cool. I didn’t make it to Zach Owen’s session on this but spent some time with the Dallas team members at the Ask the Experts reception Wednesday night and it’s clear they have some ambitious plans for this. There is more information here.
Eric Lawrence’s great session on Fiddler, which has has an amazing run of success – Eric told me at the reception that night that he’s getting up to 3500 downloads a day of Fiddler!
Matthew Kerner’s session on Azure Diagnostics, Logging and Management APIs, which was a very clear description of this area that I’ve been working in since the pre-PDC bits were dropped in mid-October. Matt did a great job of summarizing this and clarifying a few things I didn’t 100% get.
The session by Shyam Pather and Chris Anderson on ADO.Net Entity Framework 4. I kind of understood EF before this session, but this dynamic duo – with Shyam narrating and Chris typing away as if he were a voice-recognition and automatic code correction engine – was quite impressive.
A fun session on C++ improvements in VS 2010 – good to remember that the whole world hasn’t moved to XAML and C#!
Pablo Castro’s session on ADO.Net Data Services (formerly code-named Astoria) which was a very lucid and passionate description of why RESTful data services matter so much, and an impressive summary of all the sources being exposed through ADO.Net Data Services (now apparently renamed “WCF Data Services”) and the exposure of this in everything from Excel to Silverlight to Azure. Very impressive.

And the number one thing about this PDC… Steven Siinofsky’s announcement at the Wednesday keynote on Windows 7 that the Windows group had partnered with laptop manufacturer Acer to design a laptop optimized for Windows 7 – and that every PDC attendee was being given one! What a brilliant way to jump-start development for Windows 7 features like location-awareness, multi-touch, etc.

There are still a bunch of sessions I didn’t make it to that I plan to watch online.

Updated 11/24 with some additional information on Dallas.

DevDays Seattle – Scott Hanselman

MikeKelly — Wed, 21 Oct 2009 17:55:43 GMT

Lolcode.net – funny site with a domain-specific language that mimics IM syntax. Actual code

MVC

When you create an MVC project, you get default code for controllers and views but nothing for the model. ASP.Net MVC lets you use nHibernate, Linq to SQL, whatever for your data access.

The URL hierarchy is a form of user interface and in MVC the .aspx extension is gone. MVC uses the URLs to do routing - it's convention over configuration, i.e. there is no big file that defines the URL namespace - it's a convention that the URL is a controller action and there should be a controller named that.

MVC is just built on top of System.Web - there is a transition to System.Web.Mvc. WebForms is still there. It's like the difference between motorcycle and mini-van - one isn't better than the other, they are just different and for different purposes.

In the controller could create a viewmodel that goes to the database and pass that to the view. Framework doesn't require a ViewModel for a Model but it's typical to do it that way.

<%: in the view does an HTML.encode whereas <%= doesn't.

Views can be done using an .aspx extension - but no code behind anymore.

Create a model and can create a view that is strongly-typed linked to the model and will generate the details view for that. Code Templates let you change the default code generated from the wizard - using T4, the VS code generation engine.

www.nerddinner.com - if you hit it from an iPhone, detects that and the controllers and models are the same but the views are different. Code at http://tinyurl.com/aspnetmvc

DevDays Seattle – Joel Spolsky

MikeKelly — Wed, 21 Oct 2009 16:48:51 GMT

We get interrupted too much by a computer that has an agenda of its own for ourselves.

Examples:

Windows updates
Outlook: Any exceptions associated with the recurring appointment will be cancelled. Is this OK? <OK> <CANCEL> but Cancel doesn't mean cancel the appointments, it means cancel the change.
Even shutting down your computer involves a decision - shut down, restart, hibernate, sleep, …

Why are these called dialog boxes? They are an imaginary dialog between the programmer and the user. The programmer believes that users care about this dialog, but they don't. What you care about as a programmer is getting the parameter to some function you need to call and the user doesn't really care about giving you that answer. You should just figure it out. You as a programmer never have the right to put up a modal dialog box while the user is trying to do something.

Really comes down to simplicity versus power. Swiss Army knife version of software.

www.columbia.edu/~ss957/whenchoice.html - When Choice is Too Much

When there were 24 flavors of jam to choose among, only 3% purchased a jam. When there were 6 flavors, 30% - ten times as many - bought jam. People abdicate when too many choices are presented.

37signals - getting real - fewer options in software.

My manager at Microsoft, Andrew Kwatinetz, taught me every time you have an option in a dialog box, you're asking someone to make a decision.

Gmail - has a choice "Always display external content (e.g. images) sent by trusted senders." Not sure as a user why they're asking you, but as a programmer I understand the security risk of displaying an image - but even I don't know who are trusted senders.

Software excuses itself so that when someone does something natural that causes a problem, they feel stupid. This is what all these "Are you sure?" dialogs are about - so people blame themselves.

So why isn't software just simple?

When you show the V1 simple software, everyone loves the simplicity - but could they just have this one feature - why isn't there search? Why can't I add a picture to a bug?

What you find is as you solve the customer problems by adding features, you have more sales - so you're adding features to drive those sales. Yes, people only use 20% or so of features, but it's a different 20% for each person.

So how do you solve this conundrum?

Design is the act of making decisions, and designing well is making the right decisions. When you have failed at design, you are punting to the user. A designer knows he has achieved his task not when there is nothing left to add, but nothing left to take away.

A piece of architecture is best when it has the modesty not to draw attention to the obstacles it has overcome.

Nokia E71 phone - four choices for silent: meeting, outdoor, silent, vibrate. The four choices require a complicated menu. If you just have two choices - silent/ring, you can do what the iPhone does and have a physical switch.

We realize we don't need checkout, we can buy now with 1click. We don't need pause/stop - we can just have stop. Pause exists because of reel-to-reel tape where the difference between stop and pause was whether the heads disengaged. In a digital world, we don't need the distinction.

Simple is hard. Think of all the extra work the Amazon codebase has to do to make one-click work. They have to hold the order for 30 minutes in case it was a mistake so it can be cancelled - but proceeding is the mainstream case and the case that is optimized - you only have to do extra things if you want to stop the order.

DevDays Seattle

MikeKelly — Wed, 21 Oct 2009 15:53:43 GMT

I’m at DevDays Seattle, an event sponsored by Stack Overflow and Microsoft. I look at it as a day of seeing “how the other half codes”, i.e. those not using the Microsoft stack (IIS, ASP.Net, Azure, C#, etc.) but more open source tools like jQuery, mySQL, etc. One of my favorite tech bloggers, Joel Spolsky, is behind this and speaking, which I’m looking forward to. I’ll post updates during the day; topics include ASP.Net-MVC (after all, Microsoft is a co-sponsor, so I guess it’s not all about “the other half” :)), iPhone apps, Python, and Google App Engine.

Unix Time and Windows Time

MikeKelly — Sat, 17 Jan 2009 20:55:00 GMT

A little note in Portfolio magazine caught my attention: On Friday, February 13, at 23:31:30, the Unix time value with be 1234567890. This got me thinking about when the Windows time value will reach that serendipitous number, and led to some research on MSDN.

Time is a complicated topic - part of it is that there are so many different MSDN-documented interfaces that return time, including SQL, Java Script, WBEM, MFC, .NET, etc. I found this topic which gives a good overview of the various types of times in Windows. Unlike Unix, where there is pretty much a simple time_t structure that contains a 32-bit signed number. It might seem odd that Unix chooses to reduce the span of time it can represent by half by making the value signed rather than unsigned, but this is an artifact of the baseline used - January 1, 1970. So allowing for negative values allows times prior to 1970 to be represented on Unix (an interesting article about Unix time notes that Unix co-inventor Dennis Ritchies birthtime is the Unix time value -893,400,000).

The basic idea of representing time on computers is pretty simple - pick a baseline date/time and then count some increment of nanoseconds, milliseconds, or seconds since then as a numerical value. The trick is in picking the baseline, and accounting for all the oddities of leap years, leap seconds, changes in calendar, etc. But basically it comes down to some number of time units from the baseline, so when Portfolio said the Unix time will be 1234567890, it means it will have been 1,234,567,890 seconds since the Unix baseline of January 1, 1970 on February 13 of this year. Boy, how those billion plus seconds just flew by!

But Windows is more complicated (natch, some would cynically say). MSDN notes: "There are five time formats. Time-related functions return time in one of these formats. You can also use the time functions to convert between time formats for ease of comparison and display. The following table summarizes the time formats.

Format	Type	Description
System	SYSTEMTIME	Year, month, day, hour, second, and millisecond, taken from the internal hardware clock.
File	FILETIME	100-nanosecond intervals since January 1, 1601.
Local	SYSTEMTIME or FILETIME	A system time or file time converted to the system's local time zone.
MS-DOS	WORD	A packed word for the date, another for the time.
Windows	DWORD	The number of milliseconds since the system booted; a quantity that cycles every 49.7 days.

So what is called here Windows time (and so sounds like the parallel to Unix time) actually is dependent on when you booted your computer - so if you leave your machine running for a bit over two weeks, your Windows time will reach the magic 1234567890 value (actually at 14 days, 6 hours, 56 minutes).

The System time (which in usage is actually parallel to how Unix uses time_t and what the article is calling Unix time) is a structure on Windows, broken into WORD (16-bit on Win32) values for each component, i.e. hour, minute, etc. The system queries the realtime clock built into the processor and generates this structure from it; how exactly the CPU maintains that value is processor-dependent (part of the BIOS is making that translation).

So the closest thing to Unix time - the idea of a single number representing actual date and time, and so could reach a "magic value" like 1234567890 - is FILETIME. This is what is stored in the filesystem. I suspect it was created because it is less efficient to just store a SYSTEMTIME structure on disk (since it is composed of eight 16-bit values, or 128 bits of data, while FILETIME is a 64-bit value; doesn't sound like a lot of difference, but when you have millions of files, those bits add up... :))

FILETIME "contains a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601 (UTC)." So here very visibly is the difference between a 32-bit value and a 64-bit value. Remember Unix is counting seconds since January 1, 1970; Windows is counting nanoseconds (a billionth of a second - nine orders of magnitude more precise than the Unix time) since a date over three centuries earlier - and still can store it in a single integer value because it's using a 64-bit value rather than a 32-bit value. The power of exponential growth right there, ladies and gentlemen.

So when did this 64-bit value reach 1,234,567,890? Well, recall that it is measured in 100 nanosecond intervals, which are a one hundred billionths of a second, and the magic value is roughly a billion - so in fact, Windows FILETIME reached the magic value Unix will reach on Friday February 13 a little more than a one hundred seconds, or about two minutes, after midnight on January 1, 1601.

Windows C++ Exception Handling

MikeKelly — Thu, 11 Oct 2007 20:19:00 GMT

Good post on how to see the stack when an exception is thrown on Windows at http://blogs.msdn.com/slavao/archive/2005/01/30/363428.aspx

Visual Studio 2008 "Orcas" Beta 2 and Silverlight

MikeKelly — Sat, 11 Aug 2007 20:14:00 GMT

OK, have passed one hurdle in getting Scott Guthrie's Silverlight samples to work with VS 2008 Beta 2. The trick suggested by Samsp on the Asp.Net forums is to change the version numbers for the assemblies in the web.config to 3.5 from 2.0. That did the trick and resolved the missing assembly reference error I was getting when running the sample web app:

Parser Error Message: Could not load file or assembly 'System.Web.Extensions, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.

I still have a problem with the samples not seeing Silverlight installed - whenever I run I get the install logo - but I think that has to do with some GUID or version mismatch in the code.