Scott Hanselman

NuGet Package of the Week #6 - Dynamic, Malleable, Enjoyable Expando Objects with Clay

May 6, '11 Comments [26] Posted in Learning .NET | NuGet | NuGetPOW
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Hey, have you implemented the NuGet Action Plan? Get on it, it'll take only 5 minutes: NuGet Action Plan - Upgrade to 1.2, Setup Automatic Updates, Get NuGet Package Explorer. NuGet 1.3 is out, so make sure you're set to automatically update!

The Backstory: I was thinking since the NuGet .NET package management site is starting to fill up that I should start looking for gems (no pun intended) in there. You know, really useful stuff that folks might otherwise not find. I'll look for mostly open source projects, ones I think are really useful. I'll look at how they built their NuGet packages, if there's anything interesting about the way the designed the out of the box experience (and anything they could do to make it better) as well as what the package itself does.

This weeks Package of the Week is "Clay." It makes working with dynamic objects even more fun. It was written for the open source Orchard Project by Louis DeJardin with an assist from Bertrand LeRoy.

image

Enjoyable Dynamics in a Static Language

Here's a little copy/paste from a post two years ago I did on the dynamic keyword in C#. I thought it was good, so I'll include it again here.

So I asked this guy, what's up with the dynamic keyword, and what type was it exactly? I mean, C# isn't dynamic, right? He says:

"Oh, well it's statically-typed as a dynamic type."

Then my brain exploded and began to leak out my ears. Honestly, though, it took a second. Here's a good example from some of Anders' slides:

Calculator calc = GetCalculator();
int sum = calc.Add(10, 20);

That's the creation of an object, invokation of a method, and the collection of a return value. This is the exact same code, as the "var" type is figured out at compile time.

var calc = GetCalculator();
int sum = calc.Add(10, 20);

If you wanted to do the exact same thing, except with Reflection (like if it were some other class, maybe old-COM interop, or something where the compiler didn't know a priori that Add() was available, etc) you'd do this:

object calc = GetCalculator();
Type calcType = calc.GetType();
object res = calcType.InvokeMember("Add",
BindingFlags.InvokeMethod, null,
new object[] { 10, 20 });
int sum = Convert.ToInt32(res);

It's pretty horrible to look at, of course. If the object is some dynamic thing (from any number of sources), we can do this:

dynamic calc = GetCalculator();
int sum = calc.Add(10, 20);

And get the dynamic method invocation and conversion of the return type. Basically it looks just like we're calling any other object.

My buddy Rob Conery and I love dynamic languages, but we also love the .NET CLR. If we had our way, there'd be a lot more support for the Dynamic Language Runtime and the Iron.NET languages. We wrote the http://thisdeveloperslife.com website using ASP.NET Web Pages largely because it uses the Razor template engine - which feels very dynamic - and we used dynamics throughout the code.

Some folks think that static languages have no business dipping their toes into the dynamic pool, but I disagree. Successful compilation is just the first unit test, as they say, and I like the ability to pick and choose between static and dyanamic.

Expandos and Dynamic

In .NET, the Expando object is a dynamic type that lets you add and remove members to it, ahem, dynamically. It's great for dealing with dynamic data. You might do this:

dynamic myObject = new ExpandoObject();
myObject.WhateverMakesMeHappy = "Scott";

And boom, I've got a new property. You can even "cast" Expandos as other types and start using them like that type. It's crazy. Play with it.

Anonymous objects via object initalizers are nice, but once you've made one, it's stuck that way. For example, from Bertrand Le Roy's blog

Html.TextBoxFor(m => m.CurrentUser, new {
title = "User Name",
style = "float:left;"
})

See the object intializer? It makes an anonymous object, but it'll have that shape with title and style, forever.

Why is Clay needed?

In Bertrand's words:

In terms of API usability [ExpandoObject is] not very daring and in particular it does not do much to help you build deep dynamic object graphs. Its behavior is also fixed and can’t be extended.

Clay on the other hand is highly extensible and focuses on creation and consumption of deep graphs.

Clay has a clever naming convention (although you may hate it. Relax, it's a convention) where you name the ClayFactory instance "New." Yes, capital-N "New." *brain explodes again*

You can do the usual stuff with Clay that you can also do with Expando, of course. But, you can use several different techniques depending on the situation you're in, and that's where it gets interesting. Here's some examples from Bertrand and Lou, starting with the ClayFactory creation:

dynamic New = new ClayFactory();

Now this “New” object will help us create new Clay objects, as the name implies (although this name is just a convention). Then:

var person = New.Person();
person.FirstName = "Louis";
person.LastName = "Dejardin";

For instance in Clay, indexer syntax and property accessors are equivalent, just as they are in JavaScript. This is very useful when you are writing code that accesses a property by name without knowing that name at compile-time:

var person = New.Person();
person["FirstName"] = "Louis";
person["LastName"] = "Dejardin";

You can also use properties as chainable setters, jQuery-style:

var person = New.Person()
    .FirstName("Louis")
    .LastName("Dejardin");

Or you can pass an anonymous object and it will become a Clay object:

var person = New.Person(new {
    FirstName = "Louis",
    LastName = "Dejardin"
});

Even better, Clay also understands named arguments, which enables us to write this:

var person = New.Person(
    FirstName: "Louis",
    LastName: "Dejardin"
);

Or even this as an array:

var people = New.Array(
New.Person().FirstName("Louis").LastName("Dejardin"),
New.Person().FirstName("Bertrand").LastName("Le Roy")
);

All of this also means that these are all equivalent:

person.FirstName
person["FirstName"]
person.FirstName()

To get started, rather than using NuGet to "install-package Clay," I'd recommend you install Clay.Sample. This is a common convention for open source projects to include sample packages that have a dependency on the project itself. Install the sample and you'll get both packages.

Here's some other cool samples that really give you an idea of how you can move like clay between the dynamic and static worlds:

public interface IPerson {
string FirstName { get; set; }
string LastName { get; set; }
}

public static void CastToCLRInterface() {
dynamic New = new ClayFactory();

var person = New.Person();
person.FirstName = "Louis";
person.LastName = "Dejardin";

// Concrete interface implementation gets magically created!
IPerson lou = person;

// You get intellisense and compile time check here
Console.WriteLine("{0} {1}", lou.FirstName, lou.LastName);
}

I'd like the see folks in power *cough* Anders *cough* check out things like Clay and make them built in. Yum.

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About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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Hanselminutes Podcast 265 - Synology Network Attached Storage and Windows Home Server with Travis Illig

May 6, '11 Comments [15] Posted in Home Server | Podcast
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Synology DiskStation - SERVER - Windows Internet Explorer (31)I chat with fellow home storage enthusiast Travis Illig about NAS options (Network Attached Storage) available today. Both Travis and I purchased (and told our friends about) Windows Home Servers. Where are our Home Servers now, and what are they using going forward?

We talk about my recent purchase of a Synology DS1511 Home Storage System and what we're doing with our Home Servers now. We also talk about the recent removal of the Drive Extender technology from WHS and our feelings on the issue.

Download: MP3 Full Show

Links from the Show

NOTE: If you want to download our complete archives as a feed - that's all 265 shows, subscribe to the Complete MP3 Feed here.

Also, please do take a moment and review the show on iTunes.

Subscribe: Subscribe to Hanselminutes or Subscribe to my Podcast in iTunes or Zune

Do also remember the complete archives are always up and they have PDF Transcripts, a little known feature that show up a few weeks after each show.

Telerik is our sponsor for this show.

Building quality software is never easy. It requires skills and imagination. We cannot promise to improve your skills, but when it comes to User Interface and developer tools, we can provide the building blocks to take your application a step closer to your imagination. Explore the leading UI suites for ASP.NETAJAX,MVC,Silverlight, Windows Forms and WPF. Enjoy developer tools like .NET Reporting,ORM,Automated Testing Tools, Agile Project Management Tools, and Content Management Solution. And now you can increase your productivity with JustCode, Telerik’s new productivity tool for code analysis and refactoring. Visitwww.telerik.com.

As I've said before this show comes to you with the audio expertise and stewardship of Carl Franklin. The name comes from Travis Illig, but the goal of the show is simple. Avoid wasting the listener's time. (and make the commute less boring)

Enjoy. Who knows what'll happen in the next show?

About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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Developer Stand up Comedy - Coding 4 Fun

May 5, '11 Comments [27] Posted in ASP.NET | Coding4Fun | Musings | Speaking
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imageThere aren't enough funny developer talks in my opinion. Lots of you folks are so funny in person and when I got to conferences or just have lunch we laugh and laugh. As with all niches or cliques, we're all part of a little club of inside jokes and shared stories.

It's always weird to get lots of comments on my technical talks. Many are positive, but sometimes I'll get one like "your not funy!" or "stop joking and start coding." Well, I realize my brand of edutainment isn't for everyone.

That said, this talk is happily content-free. If you hate my jokes, you may ignore it. ;)

Many years ago I did some local open mics and stand up, although I've never really put together a tight hour of material. I'm less of a stand up and more of a storyteller. Anyway, I got signed up for a talk in Holland last week called "Coding 4 Fun" but didn't prepare anything. I was already signed up for 6 other talks and had already presented 3 times by the time I showed up on stage at the 7pm "geek night" session.

There were a bunch of people there almost an hour early so I just sat on the end of the stage and we chatted. It was great fun. Next thing we knew, the guy was recording the video and the room was filling up.

So, I talked and told stories and chatted my co-workers and friends on IM for a while, the showed some community built NuGet packages. The only think I wish is that you could see the audience in this video. They were fun and engaged and silly.

Big thanks to Glenn Block and Clemens Vasters for sitting in the front row and playing along, and to Damian Edwards, Tim Heuer and Phil Haack for being silly over IM.

A lot of the jokes are in the IM or the code, so if you can't see them (even though I zoom in) with smooth streaming, download a higher res version so you can see them.

Coding for Fun with Scott Hanselman recorded in Holland in April of 2011

I hope you enjoy. Maybe one day I will put together a real act of "stand up for developers."

About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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Should I use HTML5 or Silverlight? One man's opinion.

May 4, '11 Comments [75] Posted in ASP.NET | Musings | Silverlight
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I was in Belgium and The Netherlands this last week presenting and talking to folks in the community. After I presented on ASP.NET MVC 3, HTML5 and jQuery, one fellow came up after and said, "Should I use Silverlight or HTML5. I don't understand what Microsoft's strategy is or what to use in my app."

Since I work for the Web Platform and Tools team (ASP.NET, IIS, etc) I spend a lot of time working, coding, and thinking about the web. However, I'm not an official strategist, or marketing guy.  But I do have an opinion; one that is mine and no one else's.

That said, I don't think it's that hard and I'm surprised there's so much confusion about this (both outside and inside Microsoft.)  Companies have their official positions but then there's the realities of the web. Here's what the young man asked me and what I told him.

NOTE: I'm talking only about Silverlight in web browsers, not Silverlight for Phone, Games, Out of Browser, High Trust, and other environments that are uniquely Silverlighty.

Should I use HTML5 or Silverlight in my Applications? If you're embracing jQuery, where does Silverlight fit in?

Even though browsers like Chrome release and update very often, not every company is going to upgrade all their browsers every week or even twice a year. Some enterprises will be on Firefox 3.6 for a while longer, or (hopefully not) IE6. Browser plugins like Silverlight and Flash can add new functionality faster. They are called plugins for a reason. They plug-in and add something.

HTML5 isn't 100% done, but today it's already a collection of things that can be used now. Your web apps should use techniques like progressive enhancement to detect available features. As newer browsers include useful features like geolocation and video that used to require plugins, then older plugins become unnecessary. Plugins rev and add new more advanced features like DVR-like video and hardware-accelerated 3D. Those features will eventually find their way into browsers in a few years and the cycle will continue.

Silverlight 5 will become Silverlight 6, Flash 10 will become Flash 11 and HTML5 will become HTML6. Each new spec will add new features, innovating, and pushing the others forward . The web will be pushed forward by all these and more.

There's no question that advanced media apps, 3d, DVR video scenarios shine on Silverlight. Silverlight CAN do some things that HTML5 can't.

If you are creating an application for the web that needs images, links and text boxes, some animations and interactivity, there's no reason you shouldn't use HTML. With new JavaScript libraries like Modernizr, jQuery along with Polyfills, you can even use many HTML5 features and still have good functionality on ALL major browsers - not just the most recent generation.

If your application is internal or a line of business app and is what I call a basic "text boxes over data" application, you have a few choices. You can certainly use Silverlight and its databinding features, or you can use JavaScript libraries like KnockoutJS and write it in HTML. It depends on where you and your company's core skillset lies. Both are good choices and both aren't going anywhere.

If Silverlight has a feature that you need that isn't a part of mainstream browsers, consider a web app that is both HTML/JavaScript and Silverlight. I'm consistently surprised that people feel the need to make Silverlight apps that fill the entire browser but consist of mostly text, images, links, etc. Don't try to make Silverlight act like it's HTML. It's not. Plugins are complimentary to the web, they are not the web. Use them in complementary ways to make the best experiences you can.

If you need basic video like YouTube, use <video> tags if your browser supports the codecs you need, and a plugin if not. However, if you need live video, adaptive smooth streaming, DVR functionality, H.264, or other features that aren't part of HTML5, then again, use a plugin.

Also consider your own productivity and happiness and the tools you want to use. Think about your users, your dev team and their overall happiness.

Apps in C and C++ have their place in games and uniquely native scenarios. Apps using managed languages and XAML balance easy development and deployment flexibility. Apps in HTML and JavaScript work everywhere on the web. Perhaps one day we'll be able to easily mix and match these styles in the best of all worlds.

Until then, it's simple. Use HTML when it makes sense to your solution. Use a plugin when it provides unique functionality. Rinse, repeat. Apply common sense, and a little hair gel.

About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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TechDays/DevDays Netherlands and Belgium:

May 2, '11 Comments [11] Posted in ASP.NET | ASP.NET MVC | NuGet | Open Source | Speaking
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Last week I was in Belgium and The Netherlands speaking at TechDays. A number of those videos are online at Channel 9. It was a great time. Here's the talks I gave. Sorry there's three screenshots of my big head to follow.

DevDays Keynote

image

The first 10 minutes or so of this are in Dutch, but you can fast forward to my part if you like. I'm about 20 min right after Arie stops talking. I talk about what Microsoft has built this year, what we are doing around Open Source, and how I see things snapping (and how they snapped) together from VB3 until today.

NuGet In Depth: Empowering Open Source on the .NET Platform

image

In this talk I start from the absolute basics of NuGet, how to make and publish a package and I work up to my thoughts on NuGet in the Enterprise and NuGet with Commercial Software. Then I show extreme examples of NuGet packages.

MVC 3 – 101: Beginner to Advanced

image

This is a 101 level talk. I start from the most basic ASP.NET MVC site, and move quickly through the basics, through the new Scaffolding changes, MvcScaffolding and finally OutputFilters.

In the evening I hosted a silly "Coding 4 Fun" session where I talked about my remote camera setup, chatted and teased Phil Haack, Tim Heuer and Damian Edwards, and told stories about working at Microsoft. It was definitely irreverent to say the least. I think it was taped and I'll post it as soon as I see it's up.

Hope you enjoy them! Remember, if the smooth streaming doesn't work, you can always download the offline versions.

About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.