For a typical .NET developer, building a distributed application of web pages and services involves using IIS. But do you really need a full blown web server like IIS? Building a functional distributed application outside IIS is possible and quite easy. Inspired by lightweight frameworks like Java's Jetty and Python's Bottle, we'll look at creating lightweight sites and services in .NET using Nancy. We'll see how using lightweight frameworks allow you to focus on your business logic without letting heavyweight frameworks and processes get in the way.

1. Thanks to our
AWESOME
sponsors!

2. ControlFreak’s
Simplist’s
A Minimalist’s Attempt at
Building a Distributed
Application
David Hoerster

3. About Me
 C# MVP (Since April 2011)
 Sr. Director of Web Solutions at RGP
 Conference Director for Pittsburgh TechFest
 Co-Founder of BrainCredits (braincredits.com)
 Past President of Pittsburgh .NET Users Group and organizer of recent Pittsburgh Code Camps and
other Tech Events
 Twitter - @DavidHoerster
 Blog – http://geekswithblogs.net/DavidHoerster
 Email – david@agileways.com

4. The Minimalist’s Goals
 Easy setup and install
 Able to deploy almost anywhere (low dependency)
 Contained intent
 Anti-Scavenger Hunt Development
 Convention favored over heavy configuration
 But I have control if needed
 No significant performance hit
 Improvement preferred!
 PhD not required

5. What Do These Have in Common?
Run from a console
Full featured web app aspects
No need for IIS or installed web server
Jenkins/Solr are JVM; Raven is .NET

6. My Project
 Have a demo app for using Solr in .NET
Solr
 Works great, but dependent on IIS
 Want to make it more like Solr
 Install anywhere
Client
Nancy
IIS
(.EXE)
(WP)
 Easy to set up and get running
 Very configurable
 Multiple instances running
SQL

7. Is IIS Evil?
No!
But…
Not everything
requires a hammer

8. Basic ASP.NET MVC Operation
Controller derives from
Controller
public class QuoteController : Controller {
Specific return types
private readonly QuoteRepository _repo;
public ActionResult Index() {
var quotes = _repo.GetAll();
return View(quotes);
}
}
Helpers that do help…
But what’s the route??
(Have to look in global.asax.)
Web API improves on this with declared return
types (e.g. List<T>) and Web API 2 will have
annotated routes (which takes a lot from Nancy).

9. What About Bottle (Python)?
Here’s my route
Intuitive method name
@bottle.route('/quote')
def get_all_quotes():
l = solr.query(‘*:*’)
# do some Python projection here to get ll
Tells I’m returning a
template, what the
template is, and what
model(s)
return bottle.template(‘quotes_template', dict(myquotes=ll))

10. Simplicity over Power
 ASP.NET MVC (and Web API) has a lot of power
 With power comes great responsibility
 Conform
 Sometimes lose intuitiveness of code
 Routes defined elsewhere
 Changing in Web API
 Other configuration throughout app

11. Get Quotes in Nancy
public class QuoteModule : NancyModule {
private readonly IQuoteRepository _repo;
public QuoteModule(IQuoteRepository repo) {
_repo = repo;
Here’s my route and method
Get["/quote"] = _ =>
{
var quotes = _repo.GetAll();
return View["Index.cshtml", quotes];
};
Returning dictionary with
template and model
}
}

12. Nancy Differences with ASP.NET MVC
 Simple design to create web methods
 No method names – dictionary of routes and funcs
 Route configuration right in with method definitions
 Good or bad? Hmmm….
 Bare bones distributed service environment
 Low overhead / low ceremony service definitions
 Not heavy on configuration
 However, full async/await support not there…yet

13. Modules and Routing
 Modules are like Controllers
 Contain routes and route rules
public class QuoteModule : NancyModule {
private readonly QuoteRepository _repo;
public QuoteModule() {
_repo = new QuoteRepository();
Get["/quote"] = _ =>
{
var quotes = _repo.GetAll();
return View["Index.cshtml", quotes];
};
 Essentially all defined in Module constructor
 Watch that business logic doesn’t creep in
 Modules could get unwieldy
}
}

14. Modules and Routing
In MVC, what’s my action?
Needs to be part of the route, unless default
 What happens here?
 http://localhost/quote/100 (GET)
http://localhost/quote/100 (GET)
http://localhost/quote/delete/100 (DELETE)
 http://localhost/quote/100 (DELETE)
Nancy has dictionaries for actions
Get[“/quote/{id}”] = args => { … }
Delete [“/quote/{id}”] = args => { … }

15. Modules and Routing
 Nancy’s routing is based on
 Method
Get[“/quote/{id}”] = args => { … }
Delete [“/quote/{id}”] = args => { … }
 Pattern
 Action
 Condition (routes can have conditions)
/quote/getall
/quote/{id?} (optional capture segment)
/quote/(?<id>[a..zA..Z]*) (regex)
Post[“/quote”, x => x.id > 0] = args => {…}
Post[“/quote”, x => x.id < 0] = args => {…}

16. Finding Modules
 Nancy scans app for NancyModules
 Loads them
 No need to define routes in config or global
 Nancy favors convention over configuration generally

17. Changing Behavior
 Nancy is a pipeline
 Series of events for each request
Request
 Want forms authentication?
 Add it to the pipeline
Auth
Error
Handler
Custom
Before
Actions
 Want custom error page
 Add it to the pipeline
 Steps can be added at application, module and route level
 Allows fine grain control for distributed app dev
Module

18. Changing Behavior
 Creating a custom bootstrapper allows for custom behavior at app level
 Before and After Hooks for application and module
 Logging and events
 Page Handlers for page type specific behavior
 Handle custom 404’s
 Static files
 If outside of /Content, need to configure in Bootstrapper
pipelines.BeforeRequest += (ctx) =>
{
Logger.Log("starting…");
Command.Enqueue(new Command());
return null;
};
pipelines.AfterRequest += (ctx) =>
{
Logger.Log("ending request");
};

19. Authentication
 By default, none
 Somewhat bare bones, but gets the job done
var formsAuthCfg =
new FormsAuthenticationConfiguration()
{
RedirectUrl = "~/login",
UserMapper = container.Resolve<IUserMapper>(),
};
 Configure through Bootstrapper
FormsAuthentication.Enable(pipelines, formsAuthCfg);
 Forms Authentication module is available
 Get it from NuGet

20. Content Negotiation
 Nancy detects the Accept header on a request
 If applicable, will return data in that form
 Default formats are
 JSON
 XML
 View
Get["/api/quote"] = _ =>
{
return _repo.GetAll()
.Quotes
.ToList();
};
 Also configurable via Bootstrapper
 Gotcha! XML needs to be materialized, not deferred (List<> vs. IEnumerable<>)

21. Dependency Injection
 By default, TinyIoc is built in
private readonly IQuoteRepository _repo;
public QuoteModule(IQuoteRepository repo)
{
_repo = repo;
 Nancy co-developer’s project
 Works well – rated as average on IoC Benchmark by Daniel Palme
 Able to use IoC of choice
 Configure through Bootstrapper
 Example with Ninject
 Built in IoC allows automatic (magic?) injection of instances into Modules
How did this get here?

22. Performance (Requests/Second)
NancyFX and IIS 8.5 Requests/Second
160.00
140.00
120.00
100.00
80.00
60.00
40.00
20.00
SU-20-1
SU-100-1
SU-500-1
MU-50-5
NancyFX
IIS 8.5
MU-100-10
MU-500-5
MU-1000-10

23. Performance (Time/Request)
NancyFX and IIS 8.5 Time (ms)/Request
50.00
45.00
40.00
35.00
30.00
25.00
20.00
15.00
10.00
5.00
SU-20-1
SU-100-1
SU-500-1
MU-50-5
NancyFX
IIS 8.5
MU-100-10
MU-500-5
MU-1000-10

24. The Minimalist’s Goals - Recap
 Easy setup and install
 Able to deploy almost anywhere (low dependency)
 Contained intent
 Anti-Scavenger Hunt Development
 Convention favored over heavy configuration
 But I have control if needed
 No significant performance hit
 PhD not required

25. What’s Next?
 Nancy + Katana (OWIN)
 Other ASP.NET components moving to pipeline model
 Be able to plug in SignalR and other pieces into Katana
 Great article in MSDN Magazine about Nancy + Katana + SignalR + WebApi
 Custom view renderers
 Custom pipeline components

26. Resources
 NancyFx Site: http://nancyfx.org/
 Documentation: https://github.com/NancyFx/Nancy/wiki/Documentation
 Howard Dierking on Nancy and Katana: http://msdn.microsoft.com/enus/magazine/dn451439.aspx
 Dependency Injection Rankings: http://www.palmmedia.de/Blog/2011/8/30/ioccontainer-benchmark-performance-comparison
 Session Code: https://github.com/DavidHoerster/Minimalist.Solr
 Slides: http://www.slideshare.net/dhoerster/a-minimalists-attempt-at-building-adistributed-application