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Introducing the XML Assembly Generator



OK, so I'm back… with a gift to the world. For the last month or so I've been working on a project in my spare time that has already been a great help in my architecture and development work. About a month ago I got COMPLETELY fed up with writing code manually and I've always despised UML and graphical code generation systems (like Visio for Enterprise Architects-- I hate Visio anyhow!), but I'm completely addicted to XML and have been for years. What I wanted (demanded!) was a declarative (NON GUI!!!!!) programming tool that allows brainstorms/architectures/projects to be written in pure XML, so that I can think in concepts without having to work directly with code. So, I decided that it was about time that I create a system that will compile a XAML-like structure to a complete VS2005/C# project.

The system has already been a tremendous help to me. In fact, when I got the initial features of the system setup, I used it to create the rest of the system. This helped speed up development because I think in terms of trees, branches organization, and XML. When I was architecting the internal components of the compiler, I was doing all my work in XML using my XAML-like format. Then, when I got a design I kinda liked, I would run it through my compiler (at the time just a console application) and VOOM I got my C# project.

So, as of today, I'm releasing to the public in alpha form under the project-name "XAG" or "XML Assembly Generator". I considered the project-name "XAC" for "XML Assembly Compiler" as it's more of a compiler than anything else... but "XAC"? That's a real name and I found that beyond lame.

Though there is a complete documentation page linked from the XAG start page, here are some of the features that XAG provides.

  • Creation of classes
  • Creation of structs
  • Creation of enumerations
  • Creation of delegates
  • Creation of interfaces
  • Creation of physical folders
  • Creation of custom attributes
  • Creation of type aliases ("using A = B;")
  • Automatic Interface Implementation
  • Usage of Polymorphism
  • Strongly-linked objects (the resource "x:Key" subsystem)
  • Inclusion of properties
  • Inclusion of fields
  • Inclusion of constructors
  • Inclusion of methods
  • Inclusion of events
  • Auto generated constructors for properties
  • Static members
  • ref and out parameters
  • Inline instantiation of properties and fields
  • Inclusion of app.config data
    • I would like to point out a few special features of the system besides what should be obvious. First, I tried to make the syntax as close to XAML as possible, including the concept of resources. So, not only can you create types, but you can strongly-link types together just like you can do in XAML with resources. For example, you can create a class called "Item" and give it a key of "MyItem01" then you can create another class and declare a property using the type referring to the key "MyItem01". XAG will do all the magic for you in finding the real name of the type. This same concept is used for many things including inheritance, interface implementation, and aliasing generics. This helps you keep your structures strongly-linked, so you can ensure that when you want to inherit from a specific class named "MyClass" you get the specific one you want, not another one with the same name, but in a different name space. This also decouples the name of the type from the key. So you can rename the class all day long and not have to update any references. As a side note, just like with WPF/XAML, in order to access a resource, you have to first declare it. I don't think that's too much to ask.

      Second, have you ever created a type with multiple properties and then had to create a constructor to set all the properties? I hate doing that. I appreciate it when it's done (who isn't frustrated at the WPF guys forgetting to do that on their UIElements!?), but still... it just seems like work that should be done for you. C# 3.0 makes this work easier... but XAG simplifies this for you today. So, when you want to create a class with properties that has a constructor to set the properties, simply create the class and the properties and set AutoGenerateConstructorsByProperties to true and BAM, your type will magically have a constructor (in addition to the parameterless one) that maps parameters to properties.

      Third, when compiling the XML to C# (or VB2005 or IL or whatever the destination is--given I add those abilities), XAG looks for compliance to many coding practices. For example, if you try to set a class field to public, the compiler will give a warning and tell you it's changing it to private. I personally hate it when people write code that doesn't obey the .NET coding laws. So, I'm not allowing some of the most common things that lead to screw ups. Also, structs have many rules that are enforced. In fact, structs have more rules enforced than all other types combined. This is not so much for compliance to the .NET coding laws, but, rather, because structs just have more rules than classes. For example, say you have a struct with three instance Int32 fields and you want a constructor. Well, first off, you can't have a parameterless constructor and secondly, if you have a constructor at all, you have to initialize all the fields before control leaves that constructor. When creating constructors, XAG knows about your fields and initializes them for you.

      Here are some sample XML documents that will compile to VS2005 projects:

      The simplest ever:

      <assembly />

      Something a bit more interesting:

      <Assembly xmlns:x=" http://www.jampadtechnology.com/xag/2006/11/ ">
        <MyClass x:Key="MyClass" Type="Class" Namespace="ClassNamespace" />
      </Assembly>

      OK, that wasn't interesting at all... So, here's one that should explain things a bit better:

      <Assembly xmlns:x=" http://www.jampadtechnology.com/xag/2006/11/">
        <MyClass x:Key="MyClass"
                   Type="Class"
                   AutoGenerateConstructorsByProperties="True"
                   Namespace="ClassNamespace">
          <Properties>
            <Id Type="Int32" />
            <Name Type="String" />
          </Properties>
        </MyClass>
      
      
        <MyOtherClass Type="Class" AccessModifier="Public" Inherits="{Type MyClass}" Namespace="ClassNamespace" />
      
      
      </Assembly>

      This last one creates a project with two classes, one inheriting from the other. The first class has two properties and two constructors, one which is parameterless (as you should always have!) and one which takes two parameters and sets them to their respective properties.

      Looking at that, you may think it's too much overhead. Well, this isn't a sissy C# file creator. This thing actually creates the entire project and returns it to you as a single zip file. So, even if you wanted to start a new project, this system will help you tremendously. Simply open the XAG screen, select a template (optional), type in your code, hit Create Project, and you'll immediately get a ZIP file containing all folders, all files, an AssemblyInfo.cs file, and the project file. You will have everything you need to start your solution or to continue your solution by simply adding the XAG project to your existence solution.

      The XAG website also currently has a few tools you may find useful. Not only can you use the initial screen to create your XAG projects, but you can also use it to check for well-formed XML and also to format your XML. The entire website is Ajax based, so responsiveness is unsurpassed. As a side note, in case anyone is wondering, I did all the Ajax code manually as I find it much more efficient than using Atlas, however... I am using Atlas for web service calls to the main compilation server.

      As a warning, I'm still cleaning up the website (it's alpha!) so there may be problems in selling all compilation errors. I'm also redoing major parts of how compiler warnings are displayed, so, for now, there might not be any compiler warnings (it depends on when you look at the site!) Ideally, I would like the system to give a list of compiler errors and warnings to the end user (you!) It does in the console version, but I've yet to completely add that to the website.

      In the future I'll probably be modifying the syntax a bit (and therefore adding a release notes/change log here) and adding a few features and simplifications that I've been meaning to add for a while. For example, I wrote a much more powerful subsystem for generics, but decided that I should hold off on a public release of that to version 2.0. I will also be monitoring the exception logs and fixing bugs as they come up. I'm sure I'll be adding a ton of "if(v != null)" in this initial release.

      You can access this application at http://www.jampadtechnology.com/xag/. You can hit the intro link to see how it works, but it's fairly obvious. Most importantly, PLEASE SKIM THE DOCUMENTATION. I didn't say read it. Only super-geeks with no lives READ documentation. Just skim it and take in the overall idea and syntax. Lastly, please feel free to use any examples in the documentation, documents in the samples section (which I will be expanding upon), or provided templates to start or assist in your usage of the system.

      Links

WCF Relative Binding Speed Demo Updated



Last year I released a simple demo showing the relative binding speeds of the various native bindings in WCF. Since that time, WCF the syntax has changed a bit making my original code obsolete. Now I'm posting the the source code based on the final version of WCF.

Here are the changes I made (most are simply to update):

  • The client proxies changed from "Proxy" to "Client"
  • <service type="..."> changed to <service name="...">
  • The 'mex' binding was added.
  • ServiceEndpoint was moved to System.ServiceModel.Description
  • On the service interface, the ServiceContract attribute ProtectionLevel was set to ProtectionLevel.None so that security is not required, thus giving a more accurate benchmark.

You can use these as a bases for you own services, but you may also wish to look at my XML Assembly Compiler which has a WCF service template. You can simply select the template, perhaps design a few types and interfaces, and let it create your entire WCF project for you.

Links

Data Feed Framework - February 2007



Back in late 2005 I created a system which I'm now calling the Data Feed Framework (DFF) to greatly simplify the creation of RSS feeds and the aggregation of RSS and Atom feeds on web sites. The goal of the feed creation portion of the system was to allow developers and IT professionals to create RSS feeds with little to no work at all thereby allowing them to use RSS for purposes other than blogging or news. The goal of the aggregator portion of DFF was to the integration of information into ASP.NET 2.0 pages.

The Data Feed Framework has two primary components :

  • FeedCreation
  • InfoBlocks

Using the FeedCreation mechanism, developers and IT professionals can quickly create RSS feeds to monitor internal SQL databases, create sales RSS feeds for management, or monitor whatever else they wanted. The aggregator portion of the system, called InfoBlocks, allows web developers to declare a control in ASP.NET 2.0, give it an RSS or Atom feed and walk away having an InfoBlock on their page containing a list of feed entries for the RSS feed.

The two portions of the system work together, but can also be used separately.

To make explaining this a bit easier, below is a link to my documentation for the system. Below that are the links for the source of the system as well as screen shots. I'll soon be creating a video to go over the basic concepts of this system.

I can't over emphasis how simply this system makes RSS creation and RSS/Atom aggregation. It's literally a matter writing a SQL statement. Absolutely no more work than that is required. The simplicity is very much like that simplicity in WCF. Where WCF relies primarily on attributes and a config file, I rely simply on a SQL Server 2005 table called "FeedCreation". You literally write a SQL statement and give it a name and you have a complete RSS feed ready for corporate or public distribution. I'm planning on incorporating this system into the core of Minima in the next CTP.

The license for this is simple: use it all you want for whatever you want, customize it to your own needs, but 1) ALWAYS keep the copyright notice in there and 2) I nor my companies are liable for anything. The typical stuff…

Update: This project has been renamed to SQL RSS Services and has been updated for .NET 3.5 using LINQ and the syndication feed support in WCF.

Related Links

XmlHttp Service Interop - Part 3 (XML Serialization)



In this third part of the series, I discuss how to manually create an XML service and a SOAP service using XML serialization to maximize the flexibility in your service interop work. The technique allows you to very quickly accept just about any XML format from the wire and work with it in a strongly typed manner in your .NET applications.

Minima and Data Feed Framework Renamed and Explained



As of today I'm renaming any of my CTP releases to simply… "releases". That is, my Minima February 2007 CTP is now "Minima - February 2007 Release" and my Data Feed Framework February 2007 CTP is now "Data Feed Framework - February 2007 Release".

The motivation behind these is different for each. With regard to Minima, I knew it wouldn't be a long term or real production project, so announcing it as a CTP was a mistake on my part. Not a big deal. Lesson learned. Furthermore, I knew from the start that it would be more of a training tool than anything else. With regard to my Data Feed Framework (DFF), after using it in various areas I realized that my initial release was sufficient for most scenarios.

As a reminder… what is Minima? Minima is an ASP.NET 2.0 blog engine built using a SQL Server 2005 database and an LLBLGen Pro 2.0 DAL that provides the base functionality that most technical bloggers would need. Since it's initial release I've added some functionality to my own instance of Minima and have used the February 2007 release as a training tool numerous times. Moving forward I want to make it very clear that Minima is primarily a training tool and a such, it's a blog template that people learning ASP.NET can enhance and upgrade to aide in their own personal learning. Having said that, Minima is a full fledged blog engine and it does have features such as labels and the ability to have more than one URL point to the same entry. In any case, if you want something to help you learn the various components of ASP.NET, please feel free to take Minima and use it as you please (see attribution/licensing note below).

By using Minima as a training tool you can learn much about base ASP.NET technology as well as manual Ajax prinicples, CSS theming, HttpWebRequest, proper use of global.asax, framework guidelines, and type organization. Furthermore you can use it to learn WCF, the power of HTTPHandlers, and how to effectively utilize LLBLGen Pro. I will try to release versions of Minima to demonstrate the new technologies of the day. For example, when ASP.NET Ajax matures a bit (I find it slower than a dead turtle right now), I'll be adding portions to demonstrate ASP.NET Ajax. However, I will not be adding new functionality for the sake of functionality. If the functionality can be used as a training tool, then I will add it. Also, Minima is a great way of learning WPF. How so? I deliberately did NOT include a client! Why? Because I would rather you use whatever you want to use to create a simple form to access the API via WCF. The client I use a very basic WPF client that calls the Minima WCF service. So far, Minima has been a very effective learning tool and I hope you will find it useful as well.

As far as my Data Feed Framework (DFF). What is it? It's a self-contained framework that converts SQL statements into RSS feeds. I've used this in a number of places where creating a manual RSS feed and MANAGING the RSS feeds would just be too time consuming. For example, say you have a ASP.NET 2.0 e-commerce website and you have new products released at various intervals. Well, it would be AWESOME if you had an RSS feed to announce new products and sales without having to send out an ethically questionable e-mail blast. With DFF, you simply write something like "select Title=ProductName, Description=ProductDescription from Product where ProductDate > '7/11/07' order by ProductDate desc" and BAM you have an RSS feed. Since an RSS feed is simply a select statement in a column in a row in a SQL Server table, you could also use it to dynamically create a custom feed for each person who wants to monitor the price of a certain product. It's very flexible. RSS feeds are accessible via their name, their ID, or you can use a "secret feed" to force a feed to be accessible via GUID only. DFF also includes some templating abilities to help customize the output of the RSS feed. In addition to the DFF SQL to RSS engine, DFF also includes an ASP.NET 2.0 control called an InfoBlock that allows you to consume any RSS feed and display it as an XHTML list. You can see an example of how to use an InfoBlock my looking at my blog. The boxes on the right are InfoBlocks which allow me to manage my lists using a SQL Server table (the DFF database contains a Snippet and a SnippetGroup table to store autonomous information like the information in these lists--please see the documentation for more information). DFF is creating secret RSS feeds that my own personal version of Minima then consumes. With this as an example, it should be easy to see how DFF can be used in portals. My DFF demonstration video shows a bit more of that.

For more information regarding my Data Feed Framework (DFF), please skim the concise documentation for Data Feed Framework linked below. It would also probably be a good idea for you to watch my short video documentation for DFF as well. Please note that even though DFF is designed to be a production framework, it too can be used as a training tool. The most obvious thing you can learn is how to create data-bound server controls for ASP.NET 2.0 as this is exactly what an InfoBlock is.

You may use either the SQL->RSS engine or the InfoBlock portion or both. It's up to you. Also, as with all my .NET technologies that I create, the source and database files are included for extensibility and so you may use these as training tools (for yourself or for others). Lastly, for both Minima and Data Feed Framework, please remember to keep the license information intact and make it very clear that your work either uses or is based on either whichever product you are using.

Minima - Links

Data Feed Framework - Links

NetFXHarmonics SolutionTemplate/E-Book



Recently I started putting together my standard .NET solution template for public release. This template contains the base architecture and functionality that all my projects need. This template is also organized in a very clear way that clearly separates each type of element into it's own section to maximize expansion and ease of development.

In order to make sure that the solution is understandable by many different types of developers, there are commentaries in each file in the solution. In addition to this, many of the files have full chapter-length lessons on a development topic contained in that file. For example, in the Code/SampleDomManipulator.js file, I wrote a rather extensive introduction to JavaScript browser dynamics through DOM manipulation. Because of these lessons, this solution template is also living .NET e-book.

Here is a list of some of the topics I've written about in this first release of my solution template, some of them are simple explanations and others are lengthy detailed lessons.

  • HttpHandler Creation
  • HttpModule Creation
  • HttpHandlerFactory Creation
  •  
  • Custom Config Section Creation
  • .NET Tracing
  •  
  • MasterPages Concepts
  • Global.asax Usage
  •  
  • CSS Theming, Management, and Media-Specific Sheets
  •  
  • JavaScript Namespaces
  • JavaScript File Consolidation
  • Firefox Console Usage
  • JavaScript Anonymous functions
  • JavaScript Multicast Event Handling
  • DOM Element Creation
  • DOM Element Manipulation
  • DOM Element Deletion
  • JavaScript Event Handling with Low Coupling
  •  
  • JavaScript GET/POST XmlHttp Service Interop
  • Manual XmlHttp Service Creation
  •  
  • JavaScript/CSS/ASP.NET/C# Code Separation
  • Highly Cohesive Type Organization

This solution template could be used for the basis for production projects or as a training utility for people new to ASP.NET, people new to JavaScript, DOM Manipulation or AJAX or people who just want to learn how to organize their projects more effectively.

As with all my projects, but much more so with this one, I will be updating the solution template over time to account for more AJAX techniques and .NET technologies. I will also continue to expand the commentaries and lessons to the point where this solution itself becomes a case study, a sample application, and book all wrapped up in one.

Links

Minima, DFF, and SolutionTemplate/E-Book now in Subversion



I've recently realized how lame it is to have to download a new ZIP file each file a new version of a framework is released or when a project has some changes. So, I'm moving my projects to Subversion instead of making everyone download my ZIP files. This should help me update the projects more often and allow everyone else to get my projects easier. Please note that this replaces all RAR/ZIP files I've previously released.

Currently, I have the following projects in Subversion:

  • Minima
  • Data Feed Framework
  • NetFXHarmonics .NET SolutionTemplate With E-Book

You can access these projects with any Subversion client, though you would probably want to use TortoiseSVN for Windows development. You can access the projects at the following SVN HTTP addresses. You are free to also use these SVN HTTP locations to browse through the code in your web browser. My primary emphasis is in .NET training and education, so I do hope this helps. Also, given that my SolutionTemplate is also my e-book, you can easily look at the files there and read them online without having to download the project.

Note the /trunk/ path at the end. There are currently no projects in the tags section of the Subversion repository and, honestly, I'm still planning what to do with that section. The branches section is currently set to not allow anonymous access.

By the way, if you're unfamiliar with it, Subversion is an incredibly powerful and seamlessly easy to use revision control system that allows for code repositories (that is, code stores) to be stored in a centralized local to allow access from diverse locations. Subversion also does automatic versioning of your commits (that is, saves) to the code repository. Not just versioning as in a magic number change, but also as in it saves all versions of your files so you can go back and see your changes over time.

Subversion is used for many different reasons and some of them have nothing to do with code. For example, I've been using something similar to it (CVS) for a rather long time now to store all my documents so I can keep everything stored in a centralized location and so I can see the progress of my work. One use that I found rather interesting was that one company was using Subversion to store and provision new instances of their application. So, you can use it as a place to store your code, as a global file system, or as an application repository. Subversion stores whatever you want to store, including binary files. For more information on Subversion, see the online O'Reilly e-book "Version Control with Subversion" below.

Related Links

NetFXHarmonics Subversion Repository Update



Today a did two things that compel me to give a very short update.

First, I created a permanent and unchanging version of the Data Feed Framework in the tags/ section under February2007/. This release is the original February 2007 release and it's what you could call is the "stable" release. All version of the DFF will be stable in terms of technology, but this is also stable in terms of documentation. You can be assured that when you download the Data Feed Framework from the trunk/ that you will be getting a solid version, but perhaps the API changed and you want a specified version for that API. Well, when the API interfaces changes, then that's a new version and I will tag that one as well. So, for now there is a tagged release called February2007/ which you may use in production at any time (as other are doing already). You may get this from the following location:

Second, I added an index to the my SolutionTemplate/E-Book. This file is the LessonIndex.txt file in the project repository. This file lists only the full-length lessons and as I write more full-length lessons I will be adding on to this file (today, I added a lesson on HttpHandlers and another on HttpHandlerFactories and added them to the index.)

Also, for you convienence here is that index:

Working with Global.asax

SolutionWebsite: App_Code/SampleHttpApplication.cs

Creating ASP.NET HTTP Handlers

SolutionWebsite: App_Code/ServiceHttpHandler.cs

Creating ASP.NET HTTP Handler Factories

SolutionWebsite: App_Code/SampleHttpHandlerFactory.cs

DOM Manipulation

SolutionWebsite: Code/SampleDomManipulator.js

JavaScript Events and Anonymous Functions

SolutionWebsite: Code/Initialization.js

JavaScript Namespaces

SolutionWebsite: Code/SampleStructure.js

JavaScript Closures

SolutionWebsite: Code/SampleStructure.js

Firefox Console

SolutionWebsite: Lib/Debug.js

JavaScript Loosely-Coupled Multicast Events

SolutionWebsite: Lib/Events.js

.NET Tracing

SolutionWebsite: Services/SampleAsyncSchemaService.aspx.cs

Custom Config Sections

SolutionWebsite: /Includes.js.aspx

ASP.NET MasterPages

SolutionWebsite: /MasterPages.master.cs

Using XAG

SampleLibrary: Config/JavaScriptImport.cs

Client-Side Type Organization

Introduction.txt

CSS Architecture

Introduction.txt

Framework Design

Introduction.txt

You can access my SolutionTemplate/E-Book at the following Subversion repository path:

NetFXHarmonics Subversion Viewer



In an attempt to make my SolutionTemplate/EBook more accessible and readable, I went ahead and built a simple ASP.NET-based Subversion viewer to allow readers to view and read my SolutionTemplate/EBook online.  This should allow easier navigation of the project without actually forcing anyone to download it.  Furthermore, this really applies to all my projects in Subversion: Minima, Data Feed Framework and SolutionTemplate/EBook.

You can access the NetFXHarmonics Subversion Viewer at one of the following locations:

Basically you just access http://viewer.netfxharmonics.com/PROJECT_NAME/trunk.  It's that simple.  Hopefully these will make referencing these resources and reading SolutionTemplate/EBook a lot easier.

By the way, in case you are wondering, this viewer was created by an HttpHandler that uses the URL being accessed to figure out what path or file to look at in the Apache front-end for Subversion.  After a quick HttpWebRequest, a few regular expressions are done and a header and footer are tacked on to give the final version of the page.

Minima .NET 3.5 Blog Engine (a.k.a. Minima 2.0)



Since the original release of Minima, I've added a ton of new features to my own blog (which ran on the original Minima).  That plus the release of the .NET Framework 3.5 Beta 2, which includes LINQ, has prompted me to work further on the public release of Minima.  Thus, the creation of the Minima .NET 3.5 Blog Engine.  This is major upgrade to Minima.  Here are some of the new features…

LINQ

Though I love LLBLGen Pro (the worlds only enterprise-class O/R mapper and database abstractor), I thought it would be tremendously beneficial to build the new version of Minima on something that many more people would be able to appreciate.  Thus, I rewrote all data access components to use LINQ instead of LLBLGen Pro.  In the Minima .NET 3.5 Blog Engine, there is no LLBLGen Pro left over and thus you do not need the LLBLGen Pro assemblies.

If you are new to LINQ, then the Minima .NET 3.5 Blog Engine is something you may want to checkout.

Windows Live Writer Support (with RSD Support)

The previous version of Minima didn't have any supported blog client.  That was left as a training exercise to those using Minima as a training tool.  It did however have an extensive WCF interface that allowed simple web-service interaction with Minima.  However, since the release of Windows Live Writer (WLW) Beta 2, the need for a WCF interface and the need to write your own blog client is gone.  With this release of Minima, you simply setup your blog , point WLW at it and it will detect everything for you via the provided rsd.xml and wlwmanifest.xml files.

Metaweblog API

As previously stated, the Minima .NET 2.0 Blog Engine had a WCF interface, but this new release doesn't.  In it's place is the XML-RPC based Metaweblog API to allow for seamless interaction by WLW.

Simplified File Structure

The file structure of Minima has been greatly simplified and the number of files in the actual website is very minimal now.  If you recall, the entire idea behind Minima was that it is very minimalistic.  This doesn't mean it doesn't have many features, but it rather means that everything is organized in such a way that makes it look minimalistic.

SQL Server-based HttpHandler Management

A few weeks ago I published a simplified version of the universal HttpHandlerFactory technique, which relies on SQL Server instead of XML configuration files for HttpHandler management.  Under this model you can simply go to the HttpHandler table and put in an HttpHandler, the text used to match against a URL, and a matching type ("Contains", "EndsWith", "StartsWith", or "Default").  So, if you want to move your API from /xml-rpc/ to /962c8b59-97dc-490b-a1d1-09b55e47455b/, just go into the table and paste in that GUID over the text XML-RPC and you're done (you will probably have to kill the cache as well since Minima caches HttpHandler mappings-- just open and save the web.config file.)  Using this same HttpHandler table you can change the comment moderation endpoint (which uses the MinimaCommentHttpHandler).

Google Sitemap Creator

Minima now allows you to create a Google Sitemap simply by using the MinimaSiteMapHttpHandler registered in the HttpHandler SQL Server table.  By default it's registered to anything ending with "sitemap.xml", but by changing the path in the HttpHandler table you can instantaneously change the sitemap path.

File Mapping Support

One of the features I found that I really, really needed a few months ago was a way to symbolically link virtual files to physical files.  Thus I built a simple system that would allow me to store symbolic links in SQL Server.  Initially there is a default "catch all" folder to which all files are naturally mapped.  Internally, this is by setting MinimaFileHttpHandler to a certain path in the HttpHandler table; /materials/ by default.  For specific files that aren't in that folder, you simply add the mappings in the FileMapping table.  Theoretically, you could have multiple links to the same file using this system.

User Rights System

Since there is a public API, there needs to be some type of rights management system.  In the Minima .NET 3.5 Blog Engine, rights are done at the system and blog level and you assign rights to blog authors.  For example, an author needs the 'R' (retrieve) system right to get a list of blogs on the system (what WLW will try to do when you point it at this release of Minima) and would need the 'C' (create) blog right to post to a particular blog.  There are 'C', 'R', 'U', and 'D' rights that can be set in the UserRight table.  If it's a blog right, there is a blogId associated with the right, if it's a system right the blogId is null.  It's actually a really simple, yet effective rights system.  That the entire point of minimalism.

Access Control System (via IP address, UserAgent, and HTTP Referrer)

In a recent blog entry I alluded to an access control system I added to my blog.  This access control system allowed me to control access by IP address, UserAgent, or HTTP Referrer and based up on one of those three things I could either write a message to the browser or forward them.  So, for example, if I want to block someone trying to download my entire site I can put the following data in the SQL Server 'Access' table: 1, 'I', 10.29.2.100, 'You have been banned', null, true.  That is, on BlogId 1, for an IP Address of 10.29.2.100, show a message of 'You have been banned', don't forward them anywhere (that's the null), and enable the rule ('true').  If you want to have them forwarded to another address, just put the destination address in the AccessHttpForward column and the rule is activated immediately.

This is implemented by an HttpModule, so it's going to apply to absolutely every request coming across the system.  They won't be able to download anything off your website, not even images or CSS files.  Also, this system works on a "first hit" model.  That is, the first rule that is hit is the one that is applied.

Tracing via Reflection

This release of Minima also allows you to trace just about anything to SQL Server.  The tracing mechanism works by serializing what you give it into XML and then stores that XML in a table.  Doing something like this comes in tremendously handy when troubleshooting APIs.  Since Minima's TraceManager has a RecordMethodCall method that accepts a params array of Object types, you can send as many parameters as you want to the method and it will serialize them into XML for storage in SQL Server.  Some types are obviously no serializable, but you can always send each property of a type to the method instead of sending the entire object.

Other Features

As with all my web projects, exceptions are e-mailed to the person monitoring the system.  With this release of Minima, I added a feature that I've been using for a while: support for Gmail subjects.  Usually in Gmail, messages that look a like will be grouped together in the same conversation.  This is a tremendously time saving feature for most everything, but not when it comes to exception monitoring (or comment notification).  So, when enhanced Gmail subjects are enabled, e-mail subjects are suffixed with a long random number (actually, the time in ticks) so that no two messages are in the same conversation.  The same is done for comment notification.

Previous Features

Previous features were fairly basic and included labeling, commenting, and other blog stuff.  The biggest feature of the previous release of Minima was its ability to have more than one URL for a blog entry.  So, for example, if you accidentally blog as /Blog/2007/08/LINQ-ruels.aspx, you can add another URL mapping to that entry so /Blog/2007/08/LINE-rules.aspx, which would set as the default mapping, goes to the same place.  Both are still accessible, but the new default will be the one that shows up at the blog entry's permanent home.  The Minima .NET 3.5 Blog Engine retains this feature.

As a Training Tool

As with all my project there is an "As a Training Tool" section in the release notes.  This release of Minima can be used to train concepts such as ASP.NET, CSS theming, proper use of global.asax, integrating with Windows Live Writer, framework design guidelines, HttpModules, HttpHandlers, HttpHandlerFactories, LINQ, type organization, proper-SQL Server table design and naming scheme, XML serialization, and XML-RPC.NET usage.

To download the Minima .NET 3.5 Blog Engine simply access the following Subversion repository and download the associated sample SQL Server 2005 database:

NetFXHarmonics .NET SolutionTemplate



I've had a number of requests for my SolutionTemplate without the e-book lessons, so below is its Subversion repository:

You may still access the e-book version as well in the related links section, but if all you need is a new project to get started then you can use the above; this repository shares the same code base with the e-book version.  I will be very careful to make sure that the two versions are kept in sync to minimize confusion.

I should also mention that since the initial release, SolutionTemplate has had various substantial updates based on my more recent research.  They will both continue to be updated as I think of more foundational portions that should be put in the template.  This SolutionTemplate has helped me time and time again when starting new projects and I hope it helps you too; you can use it for any of your production projects as you please.

Lastly, in case you're wondering why this isn't a Visual Studio template: Subversion is just a better way to work with code that regularly updates.  It's an extremely versatile lightweight, transaction, distributed file system that allows for extremely efficient updates.  I would pay for each of those things, but Subversion is FREE.  Can't beat that!

Related Links

ESV Bible Web Service Client for .NET 3.5



A while back, the guys over at the ESV Bible web site announced their new REST-based interface to replace their old SOAP interface.  This new interface provides the same functionality as the old, but allows for 5,000 queries per day instead of 500 previously and is based on REST architectural principles.  Because the service is fundamentally chatty, it made sense to switch to REST.  In the context of a Bible web service, it's hard to justify a 200-byte XML message when your actual request is 6 bytes ("John 1").  Also, because the method call is in the URI, the entire call is simplified all the more.

For those of you who are completely unfamiliar with REST interfaces, all you really need to know is that it's a resource (or noun) based architecture.  That is to say instead of calling, for example, a "GetItem" method, you simply access an "item" entity.  You access what the thing is, not what the thing does; kind of a web-based reversal of encapsulation.  In other words, instead of giving a server a command (a verb), you are accessing the resource directly (a noun).  There's obviously more to REST than this and you can get more information from this nice article titled "Building Web Services the REST Way".

RESTful architecture really is a nice way to telling a system what you want, not how to get it.  This is really the point of framework design and abstraction in general.  In light of this it's obvious to see that, as awesome as REST is, it's not how .NET developers want to think when working working on a project.  When I'm working with something I want to focus on the object at hand, not on the URLs and parameters.  For this reason, I built a .NET 3.5 framework that allows easy and efficient access to the new ESV Bible REST web service.  Here are some samples of how to use it:

Here's a simple passage query returning HTML data:

ESVBibleServiceV2 service = new ESVBibleServiceV2( );
String output = service.PassageQuery("Galatians 3:11");

With the flip of a switch you can turn it into plain text:

ESVBibleServiceV2 service = new ESVBibleServiceV2(OutputFormat.PlainText);
String output = service.PassageQuery("Galatians 3:11");

For more flexibility, you may use the provided parameter objects.  Using these in C# 3.0 is seamless thanks to object initializers:

PassageQueryParameters pqp = new PassageQueryParameters( ) { Passage = "John 14:6" };
ESVBibleServiceV2 service = new ESVBibleServiceV2(new PlainTextSettings( )
{
    LineLength = 100,
    Timeout = 30
});
String output = service.PassageQuery(pqp);

Here is a simple sample of accessing the verse of the day (in HTML without the audio link -- optional settings):

ESVBibleServiceV2 service = new ESVBibleServiceV2(new HtmlOutputSettings( )
{
    IncludeAudioLink = false
});
String output = service.DailyVerse( );

You can also access various reading plans via the provided .NET enumeration:

ESVBibleServiceV2 service = new ESVBibleServiceV2( );
String output = service.ReadingPlanQuery(new ReadingPlanQueryParameters( )
{
    ReadingPlan = ReadingPlan.EveryDayInTheWord
});

Searching is also streamlined:

ESVBibleServiceV2 service = new ESVBibleServiceV2( );
String output = service.Query("Justified");

Here is a length example showing how you can use the QueryInfoAsObject method to get information about a query as a strongly-type object:

ESVBibleServiceV2 service = new ESVBibleServiceV2( );
QueryInfoData result = service.QueryInfoAsObject("Samuel");


Console.WriteLine(result.QueryType);
Console.WriteLine("----------------------");
if (result.QueryType == QueryType.Passage) {
    Console.WriteLine("Passage: " + result.Readable);
    Console.WriteLine("Complete Chapter?: " + result.IsCompleteChapter);
    if (result.AlternateQueryType != QueryType.None) {
        Console.WriteLine(String.Format("Alternate: {0}, {1}", result.AlternateQueryType, result.AlternateResultCount));
    }
}


if (result.HasWarnings) {
    foreach (Warning w in result.Warnings) {
        Console.WriteLine(String.Format("{0}: {1}", w.Code, w.Readable));
    }
}

Here is the output:

QueryInfoAsObject Example Output

For more advanced users, the Crossway XML format is also available:

ESVBibleServiceV2 service = new ESVBibleServiceV2(new CrosswayXmlVersion10Settings( )
{
    IncludeWordIds = true,
    IncludeXmlDeclaration = true
});
String output = service.PassageQuery(new PassageQueryParameters( )
{
    Passage = "Galatians 3"
});
Console.WriteLine(output);

That same XML data is also retrievable as an XmlDocument for pure XML interaction:

ESVBibleServiceV2 service = new ESVBibleServiceV2( );
XmlDocument output = service.PassageQueryAsXmlDocument("Galatians 3");

For more flexible XML interaction, you may use XPath:

ESVBibleServiceV2 service = new ESVBibleServiceV2( );


String output = service.PassageQueryValueViaXPath(new PassageQueryParameters( )
{
    Passage = "Gal 3:4-5",
    XPath = "//crossway-bible/passage/surrounding-chapters/current"
});

Sometimes, however, you will want more than one result from XPath:

String[] output = service.PassageQueryValueViaXPathMulti(new PassageQueryParameters( )
{
    Passage = "Gal 3:4-5",
    XPathSet = new[]
    {
        "//crossway-bible/passage/surrounding-chapters/previous",
        "//crossway-bible/passage/surrounding-chapters/next"                
    }
});

Here's what the result looks like the debugger:

XPathSet Example Output

I've also copied the documentation for functions and parameters into the .NET XML comments, so you can quickly and easily see what a certain function or parameter does and it's default:

ESVBibleServiceXmlComment

The new API uses your existing ESV Bible Web Service access key.  To use this key in this framework you simply add an element called ESVBibleServiceKey to the addSettings in your configuration file (a sample is provided with the framework).  You may also set it in any one of the parameter objects (i.e. PassageQueryParameters, QueryParameters, etc...), which override the key in the configuration file.  Per the API, you can use TEST for testing and IP for for general purpose queries.

Lastly, I would like to mention that this framework minimizes traffic by only sending options that deviate from defaults. So, for example, if you set IncludeWordIds to false and IncludeXmlDeclaration to true, only the IncludeXmlDeclaration value will be sent over the wire since IncludeWordIds is false by default.

You can access this ESV Bible Web Service 2.0 framework on CodePlex at the address in the links section.  Enjoy!

Links

10 Things Most Developers Didn't Know in 2007



To end 2007, I thought I would make a list of things which I found that most developers didn't know.  To make things more interesting, this list is actually a series of 10 mini-articles that I wrote today.  Since this article has several sub-articles, here's a table of contents to help you out (these aren't really in any order of importance):

#1  SQL Server supports powerful subqueries as anonymous sets.

Many developers don't take the time to seriously look at T-SQL or SQL Server internals.  As such, they miss many of SQL Server's more powerful features.  In January 2007, when co-worker saw he write the following query, he about fell out of his seat:

select MemberName, m.MemberId, count() from (select 
    distinct MemberId, 
    VisitUserAgent 
    from VisitSession 
    where MemberId is not null) a 
inner join Member m on a.MemberId = m.MemberId 
group by m.MemberId, MemberName, VisitUserAgent 
having count() > 1 
order by count(*) desc 

For starters, the guy didn't know you could do a filter after a group by, but that's not my point.  He had no idea that SQL Server (2000) allows you to use subqueries or use subqueries as anonymous sets.  As you can see, you can select from the list as well as use it in a join.  This tidbit alone should toss many painfully slow cursor-based stored procedures into the trash.  It's a simple SQL feature, but it's a powerful one.

#2  Firefox has an operating-system style console for web application debugging.

It's incredibly hard to find an ASP.NET web developer who knows this one.  It's a feature that knocks people right off their seats.  Instead of throwing alerts all over your AJAX applications, you can use the Firefox console and the dump( ) function.  Did I mention this has been a native feature since Firefox 1.0?

Step 1 (start Firefox with -console switch)

Step 2 (add the boolean key 'browser.dom.window.dump' to the Firefox configuration an set it to true)

Then simply call dump( ), instead of alert( ) and you're done. Your output will go to the Firefox console window (which looks almost exactly like a cmd window).

With this technique you can entirely avoid any possibility of having an infinite loops of alerts.  Personally, I like to track all the output of my web applications.  This comes in very handy when I'm using event capturing or need to watch the progressive state of my application.  When I do this, I also like to write an output identifier to each data dump.  Here's a sample of what I usually use for debugging:

var Configuration = { 
    Debug: false
}; 


var Debug = { 
    counter: 0, 
    write: function(text) { 
        if(Configuration && Configuration.Debug) { 
            dump(text); 
        } 
    }, 
    writeLine: function(text) { 
        if(Configuration && Configuration.Debug) { 
            Debug.counter++;        
            dump(Debug.counter + ':'+ text + '\n'); 
        } 
    } 
};

Here's some sample output using the Debug.writeLine( ) abstraction:

Leaves alert( ) in the dust, doesn't it? You can actually learn more about this technique and others from my Firefox for ASP.NET Web Developer video series found on my blog.  These topics are crucial to your understanding of modern web development.

#3  JavaScript has natively handled loosely-coupled multi-cast events for years.

This isn't something just for the Firefox, Opera, Safari world.  Even IE6 has native support for this feature. I'm not sure why this is, but in September 2007 when I was designing the AJAX exam for Brainbench, not a single one of the reviewers knew that JavaScript natively supported loosely-coupled multi-cast events.  I actually comments from almost all of the reviewers telling me that I should "leave server-side questions out of the exam".

JavaScript loosely-coupled multi-cast events are one of the most important core features of AJAX applications. They allow you to quickly and efficiently attach multiple event handlers to the XHTML same element. This becomes critically important when you are with multiple AJAX components, each of which that want to have an event handler attached to the load event of the window object.

I wrote an article about this in September 2007, so I'm not going to go into any kind of details here.  You my also opt to view this file from my SolutionTemplate, which supplements that blog entry.

#4  Not all image formats are created equal.

A few months ago, I came in as lead architect about half way through a project.  After having a few people fired for absolute incompetence, I did find a few people (PHP guys) who were ready, willing, and actually able to learn ASP.NET.  Everything was going well until the designer came back with his new theme and my associate whom I was training implemented it.  Everyone thought the project was going fine until I stepped in the room.  It didn't take but 10 seconds for a red flag to go up.  Just looking at the web site I could tell that this theme implementation was a disaster.  I noticed that there were signs of JPEG compression all over every single one of the images.  However, being a scientist and part-engineer I knew that measurement was a major key to success.  So, I whipped out Firebug, hit refresh and felt my jaw drop.  The landing page was 1.5MB.  Ouch.

You absolutely can not use one single image format for ever image on your web site, especially not the deadly JPEG format which does little more than destroy your images.  There are rules which web developers must need to follow or else a project is doomed to failure.  First off, you need to be using PNG24s for the all important images, while comparing their file sizes and quality with PNG8 compression.  Using Adobe Photoshop's Save For Web feature is very helpful for this.  If the image is a photo or something with many "real life" colors and shades, perhaps you want to do a size and quality comparison against a JPEG version as well.  If you absolutely need to have transparent images for IE6, then you need to take extreme care and either make special PNG versions for each background or, if you don't care too much about quality and the image is small with very few colors, use a GIF with transparencies.  The same goes for Firefox and printing.  Firefox (as of 2.0) does not print transparent PNG images.  So, if you want to support printing in Firefox, then you need to either make special PNG images for each background or make low-quality GIF images.

Needless to say, the designers theme had to go under severe reconstruction.  Not just because of the image sizes, but because he felt the need to design special input box, textarea, and button controls.  His design would have worked well for a WPF application, but this is the web (... but don't even get me started on the fact that his design for a wide screen monitor at over 1300x800.  The design was useless anyhow!)  The next project I ran as lead architect went much smoother.  Because it was extremely AJAX intensive, everything was minimized to the absolute core.  Each page had the minimal default.css plus it's own CSS sheet and only included the JavaScript it needed.  The web site landing page included barely anything and even had it's own extremely stripped down version of the JavaScript files.  For this project, I went from 350K in development to 80k in production.

#5  Custom server controls are not esoteric, complicated, or take too long to create.

  This seems to be a very common misconception amongst ASP.NET developers.  The reality, however, is that creating server controls is often a very trivial task.  Yet, many developers will use a GridView or other canned control for everything.  The GridView is awesome for basic tabular in a very simple, data-driven applications, but I can rarely use it.  On the other hand, I love the repeater and rely on it for almost everything.  Actually, it and the Literal are my two favorite controls.  I have to rely on these two controls to ensure that my AJAX applications are extremely optimized.  One of the beautiful things about .NET is that every ASP.NET control is simply a .NET class, which means that you can programmatically reuse them, inherit from them, and override their internals.  Thus, allowing us to create some powerful and elegant custom server controls.

On the same project with the overly sizes image files, we had an interesting meeting about how to show a media play list on a web page.  There was all kinds of talk about using Flash to create a media play list.  The conversation was quickly giving me an allergic reaction.  So, after hearing all kinds of absolutely insane quotes of time for creating a Flash play list, I decided to take matters in to my own hands.  Two hours later I handed the client a complete play list from A to Z.  To be clear, I had built this one something I had already had, but the grand total of time was them about 3 hours.  It's amazing what you can do when you understand the .NET framework design guidelines and aren't afraid to follow best-practices.

Here is how you would use a similar control:

<%@ Register Assembly="Jampad.Web" Namespace="Jampad.Web.Controls" TagPrefix="j" %>


<j:Media id="media01" runat="server" />

In your code behind, you would have something that looked like this:

media01.DataSource = MediaAdapter.GetContent(this.MemberGuid);

Upon loading the page, the data was bound and the output was a perfect XHTML structure that could them be customized in any number of ways using the power of CSS.  How do you make something like this happen?  It's simple, here is a similar control (Media.cs) placed in a class library (WebControls.csproj):

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;


namespace Jampad.Web.Controls
{
    [ToolboxData("<{0}:Media runat=\"server\"></{0}:Media>")]
    public class Media : CompositeControl
    {
        private Repeater repeater;
    <span style="color: blue">public </span>Media( ) {
    }


    <span style="color: blue">private </span><span style="color: #2b91af">Object </span>dataSource;


    <span style="color: blue">public </span><span style="color: #2b91af">Object </span>DataSource {
        <span style="color: blue">get </span>{ <span style="color: blue">return </span>dataSource; }
        <span style="color: blue">set </span>{ dataSource = <span style="color: blue">value</span>; }
    }


    <span style="color: blue">protected override void </span>CreateChildControls( ) {
        <span style="color: #2b91af">HtmlGenericControl </span>div = <span style="color: blue">new </span><span style="color: #2b91af">HtmlGenericControl</span>(<span style="color: #a31515">"div"</span>);
        div.Attributes.Add(<span style="color: #a31515">"class"</span>, <span style="color: #a31515">"media-list"</span>);


        <span style="color: blue">try </span>{
            repeater = <span style="color: blue">new </span><span style="color: #2b91af">Repeater</span>( );
            repeater.DataSource = <span style="color: blue">this</span>.DataSource;
            repeater.ItemTemplate = <span style="color: blue">new </span>MediaTemplate(<span style="color: #2b91af">ListItemType</span>.Item);
            repeater.HeaderTemplate = <span style="color: blue">new </span>MediaTemplate(<span style="color: #2b91af">ListItemType</span>.Header);
            repeater.FooterTemplate = <span style="color: blue">new </span>MediaTemplate(<span style="color: #2b91af">ListItemType</span>.Footer);
            div.Controls.Add(repeater);
            repeater.DataBind( );
        }
        <span style="color: blue">catch </span>(<span style="color: #2b91af">Exception </span>ex) {
            <span style="color: #2b91af">Literal </span>error = <span style="color: blue">new </span><span style="color: #2b91af">Literal</span>( );
            error.Text = <span style="color: #a31515">"&lt;span class=\"error-message\"&gt;" </span>+ ex.Message + <span style="color: #a31515">"&lt;/a&gt;"</span>;
            div.Controls.Add(error);
        }


        <span style="color: blue">this</span>.Controls.Add(div);
        <span style="color: blue">base</span>.CreateChildControls( );
    }
}
}

Notice the use of the repeater control.  This is the same control we use in ASP.NET as <asp:Repeater />.  Since this is .NET, we can use it programmatically to create our own powerful controls.  Also notice the various templates that are being set on the Repeater.  These are the same templates you would set declaratively in an ASPX page.  In this case, I'm programmatically assigning to these templates an instance of MediaTemplate (in MediaTemplate.cs).  This MediaTemplate.cs is just another file thrown in a class library, in our case the same WebControls.csproj, though since it's just a class, it could be in a different assembly and namespace altogether. Here's what the MediaTemplate.cs looks like:

using System;
using System.Collections.Generic;
using System.Text;
using System.Web.UI.WebControls;
using System.Web.UI;


namespace Jampad.Web.Controls
{
    internal class MediaTemplate : ITemplate
   {
        ListItemType type = new ListItemType( );
    <span style="color: blue">public </span>MediaTemplate(<span style="color: #2b91af">ListItemType </span>type) {
        <span style="color: blue">this</span>.type = type;
    }


    <span style="color: blue">public void </span>InstantiateIn(<span style="color: #2b91af">Control </span>container) {
        <span style="color: #2b91af">Literal </span>lit = <span style="color: blue">new </span><span style="color: #2b91af">Literal</span>( );
        <span style="color: blue">switch</span>(type) {
            <span style="color: blue">case </span><span style="color: #2b91af">ListItemType</span>.Header:
                <span style="color: blue">break</span>;


            <span style="color: blue">case </span><span style="color: #2b91af">ListItemType</span>.Item:
                lit.DataBinding += new EventHandler(<span style="color: blue">delegate</span>(<span style="color: #2b91af">Object </span>sender, System.<span style="color: #2b91af">EventArgs </span>ea) {
                    <span style="color: #2b91af">Literal </span>literal = (<span style="color: #2b91af">Literal</span>)sender;
                    <span style="color: #2b91af">RepeaterItem </span>item = (<span style="color: #2b91af">RepeaterItem</span>)literal.NamingContainer;
                    literal.Text += <span style="color: #2b91af">String</span>.Format(<span style="color: #a31515">"&lt;div class=\"media-item\"&gt;\n"</span>);
                    literal.Text += <span style="color: #2b91af">String</span>.Format(<span style="color: #a31515">"  &lt;div class=\"media-item-inner\"&gt;\n"</span>);
                    literal.Text += <span style="color: #2b91af">String</span>.Format(<span style="color: #a31515">"    &lt;a href=\"{0}\"&gt;&lt;img src=\"{1}\" alt=\"Media\" class=\"media-thumb\" /&gt;&lt;/a&gt;\n"</span>, (<span style="color: #2b91af">String</span>)<span style="color: #2b91af">DataBinder</span>.Eval(item.DataItem, <span style="color: #a31515">"mediaPath"</span>), (<span style="color: #2b91af">String</span>)<span style="color: #2b91af">DataBinder</span>.Eval(item.DataItem, <span style="color: #a31515">"thumbPath"</span>));
                    literal.Text += <span style="color: #2b91af">String</span>.Format(<span style="color: #a31515">"  &lt;/div&gt;\n"</span>);
                    literal.Text += <span style="color: #2b91af">String</span>.Format(<span style="color: #a31515">"  &lt;div class=\"media-item-bottom\"&gt;&lt;/div&gt;\n"</span>);
                    literal.Text += <span style="color: #2b91af">String</span>.Format(<span style="color: #a31515">"&lt;/div&gt;\n\n"</span>);
                });
                <span style="color: blue">break</span>;


            <span style="color: blue">case </span><span style="color: #2b91af">ListItemType</span>.AlternatingItem:
                <span style="color: blue">break</span>;


            <span style="color: blue">case </span><span style="color: #2b91af">ListItemType</span>.Footer:
                <span style="color: blue">break</span>;
        }
        container.Controls.Add(lit);
    }
}
}


Simply compile those to together and you're set.  You can even embed (hopefully tiny) images in your project to make things even more seamless.  Using this simple pattern, I've created all kinds of things.  You can see a real example of this, including image embedding, in my SQL Feed Framework (formerly known as Data Feed Framework).  It's InfoBlock controls follow this same pattern.  For much better examples, whip out reflector and start digging around the System.Web namespaces.

It's actually rather astonishing to learn of some of the attituted some developers have about custom controls. When I was one of the editors for an ASP.NET 2.0 exam last year, I noticed one of the questions ask which type of control was "harder" to create. The answers were something like "User Control", "Custom Control", and a few others. They were looking for the answer "Custom Control". Since "harder" is not only a relative term, but also a subjective and an abstract one, the question had no actual meaning. Custom controls aren't "harder" than user controls.

#6  Most developers I worked with in 2007 had never heard of an O/R mapper.

Why do most developers still absolutely insist on wasting their time writing a chain of SqlConnection, SqlCommand, and SqlDataAdapter?  Perhaps it's just an addiction to being busy instead of actually being productive that causes this.  I don't know.  I would, however, expect these developers have to have some curiosity that there may be an easier way.  ADO.NET is awesome stuff and it is the foundation for all .NET O/R mappers, but if I'm not throwing around 1,000,000 records at a time with SqlBulkCopy, I'm not interested in working with ADO.NET directly.  We need to have a system that allows us to get what we want instead of forcing us to screw about with low-level mechanics.  It's no secret that I'm a huge supporter of Frans Bouma's work with LLBLGen Pro and I also use LINQ in most of my .NET 3.5 applications.  For a corporate .NET 2.0 project, there's absolutely no excuse to not pay the $300 for LLBLGen Pro.  Managers!  Open the wallets!  It will save you money.

However, it's not always about the money.  Even if the developers knew about O/R mapping, and the company isn't from in a poverty-stricken 3rd world country, sometimes extreme pride, lack of personal integrity, and political alignment can destroy any chance of being productive.  A long time ago I worked at a company where I thought I would be productive.  Five or so weeks into the design phase of the project, we received a politically-focused project manager as big brother.  He was absolutely against the use of any modern technology and despised the idea of an O/R mapper.  He instead told us that we were to write a stored procedure for every possible piece of interaction that would happen.  He also wanted us to use Microsoft's data application block to access the stored procedures.  At one point he said that this was their O/R mapper, showing that he had no idea what an O/R mapper was.

A few days after his reign had started, I took an hour or so to write up a 12 page review document covering various aspects of LLBLGen Pro and how they would work on the project.  I thought it was a very convincing document.  In fact, one guy looked at it and was convinced that I took it from the LLBLGen web site.  The project manager, however, was beginning to be annoyed (this is not uncommon with me and old-school project managers!)  The project manager decided to call together a panel of his "best" offshore developers and put me in what basically amounted to be a doctoral defense.  Prior to the meeting I sent out my "dissertation" and asked everyone to read it before they arrived at the meeting so that they would be prepared for the discussion.  When it was time for the meeting, I was told to sit at one side of a large meeting table and the project manager and his team sat at the other.  Then the disaster began.  First off, not one single person on that team had read my document.  Secondly, for the next 45 minutes they asked me basic questions that the document would have answered.  Even after they admitted that I had answered all of their concerns to their satisfaction and being told by their team that LLBLGen Pro was obviously a very productive tool, they reached the conclusion that they still weren't going to use it.  It was a waste of my time and I still want those 45 minutes of my life back.

What was really interesting about my defense was the developer's code.  In the meeting, the developers had showed me their [virtually unreadable, anti-.NET framework design guidelines, inefficient, insecure] .NET project code and I was shocked to see how much time they wasted on writing the same stuff over and over and over again.  When they showed me their stored procedures, I about passed out.  It's a wonder how any of their systems run.  They were overridden with crazy dynamic SQL and cursors.  They even had most of the business logic in the data access tier.  The concept of N-tier architecture was not something that they understood at all.  I think that's the point where I gave up on my defense.  If a developer doesn't even understand the critical need for N-layer and N-tier architecture, there's just no way they will be able to understand the need for an O/R mapper.  It's actually one of the fastest way to find a coder hiding amongst professionals.  Their SQL/ADO.NET code was also obviously not strongly-typed.  This was one of the core points of an O/R mapper and these developers could not understand that.  They could not see the benefit of having an entity called Person in place of the string "Persno" (deliberate misspelling).

This project didn't really take off at all, but for what parts I was involved, I used the next best thing to an O/R mapper: a strongly-typed data-set.  Read this carefully: there is no shame in using a strongly-typed data set if you don't have an O/R mapper.  They are no where near as powerful, but they are often good enough to efficiently build your prototypes so that the presentation layer can be built   You can replace the data access components later.

The training of developers in the use of LLBLGen Pro and LINQ O/R mapping was one of the main reasons I publicly released both my Minima Blog Engine and my Minima 3.5 Blog Engine source code to the public in 2007.  You are free to use these examples in your own training as you see fit. 

For more information and for some example of using an O/R mapper, please some of my resources below:

#7  You don't need to use SOAP for everything.

This is one of the reasons I wrote my XmlHttp Service Interop series in March and May 2007.  Sometimes straight up HTTP calls are good enough.  They are quick, simple, and light-weight.  If you want more structure, you can simply use XML serialization to customize the smallest possible data format you can think of.  No SOAP envelope required.

Here are the parts to my series:

Also keep in mind that you don't need to keep JSON to JavaScript.  It's a beautiful format that could easily be an amazing structured replacement for flat CSV files.  RESTful interfaces using GET or POST with HTTP headers are also a great way to communication using very little bandwidth.  My AJAX applications rely heavily on these techniques, but I've also used them for some behind the scenes work as well.

One great example of how you can use RESTful services is by looking at the interface of the ESV Bible Web Service V2. In November 2007, I wrote a .NET 3.5-based framework to abstract the REST calls from the developer. By looking at my freely available source code, you can see how I'm interacting with the very light-weight REST service.

#8  A poor implementation of even the most beautiful database model can lead to a disast

Squid Micro-Blogging Library for .NET 3.5



A few years ago I designed a system that would greatly ease data syndication, data aggregation, and reporting.  The first two components of the system were repackaged and release early last year under the incredibly horrible name "Data Feed Framework".  The idea behind the system was two fold.  The first concept was that you write a SQL statement and you immediately get a fully functional RSS feed with absolutely no more work required.  Here's an example of a DFF SQL statement that creates an RSS feed of SQL Server jobs:

select Id=0,
Title=name,
Description=description
from msdb.dbo.sysjobs
where enabled = 1

The second part of DFF was it's ASP.NET control named InfoBlock that would accept an RSS or ATOM feed and display it in a mini-reader window.  The two parts of DFF combine to create the following:

Given the following SQL statement (or more likely a stored procedure)...

select top 10
Id=pc.ContactID, 
Title=pc.FirstName + ' ' + pc.LastName + ': $' + convert(varchar(20), convert(numeric(10,2), sum(LineTotal))), 
Description='', 
LinkTemplate = '/ShowContactInformation/{id}'
from Sales.SalesOrderDetail sod
inner join Sales.SalesOrderHeader soh on soh.SalesOrderID = sod.SalesOrderID
inner join Person.Contact pc on pc.ContactID = soh.SalesPersonID
group by pc.FirstName, pc.LastName, pc.ContactID
order by sum(LineTotal) desc

...we have an automatically updating RSS feed and when that RSS feed is given to an InfoBlock, you get the following:

image

InfoBlocks could be placed all over a web site or intranet to give quick and easy access to continually updating information.  The InfoBlock control would also register the feed with modern web browsers that had integrated RSS support.  Furthermore, since it was styled properly in CSS, there's no reason for it to be a block at all.  It could be a horizontal list, a DOM-based window, or even a ticker as CSS and modern AJAX techniques allow.

DFF relied on RSS.NET for syndication feed creation and both RSS.NET and Atom.NET for aggregation.  It also used LLBLGen Pro a bit to access the data from SQL Server.  As I've promised with all my projects, they will update as new technologies are publicly released.  Therefore, DFF has been completely updated for .NET 3.5 technologies including LINQ and WCF.

I've also decided to continue down my slippery slope of a change in product naming philosophy.  Whereas before I would follow the Microsoft marketing philosophy of "add more words to the title until it's so long to say that you require an acronym" to the more Linux or O'Reilly approaches of "choose a random weird sounding word and leave it be" and "pick a weird animal", respectively.  I've also been moving more towards the idea of picking a cool name and leaving it as is.  This is in contrast to Microsoft's idea of picking an awesome name and then changing it to an impossibly long name right before release (i.e. Sparkle, Acrylic, and Atlas)  Therefore, I decided to rename DFF to Squid.  I think this rivals my Dojr.NET and Prominax (to be released-- someday) projects as having the weirdest and most random name I've ever come up with.  I think it may have something to do with SQL and uhhhh.. something about a GUID.  Donno.

Squid follows the same everything as DFF, however the dependencies on RSS.NET and ATOM.NET were completely removed.  This was possible due to the awesome syndication support in WCF 3.5.  Also, all reliance on LLBLGen Pro was removed.  LLBLGen Pro (see my training video here) is an awesome system and is the only enterprise-class O/R mapping solution in existence.  NHibernate should not be considered enterprise-class and it's usability is almost through the floor.  Free in terms of up-front costs, does not mean free in terms of usability (something Linux geeks don't seem to get).  However, given that LINQ is built into .NET 3.5, I decided that all my shared and open-source projects should be using LINQ, not LLBLGen Pro.  The new LLBLGen Pro uses LINQ and when it's released, should absolutely be used as the primary solution for enterprise-class O/R mapping.

Let me explain a bit about the new syndication feature in WCF 3.5 and how it's used in Squid.  Creating a syndication feed in WCF is required a WCF endpoint just like everything else in WCF.  This endpoint will be part of a service and will have an address, binding, and contract.  Nothing fancy yet as the sweetness is in the details.  Here's part of the contract Squid uses for it's feed service (don't be jealous of the VS2008 theme -- see Scott Hanselman's post on VS2008 themes):

namespace Squid.Service
{
    [ServiceContract(Namespace = "http://www.netfxharmonics.com/services/squid/2008/03/")]
    public interface ISquidService
    {
        [OperationContract]
        [WebGet(UriTemplate = "GetFeedByTitle/{title}")]
        Rss20FeedFormatter GetFeedByTitle(String title);


        //+ More code here
    }
}

Notice the WebGet attribute.  This is applied to signify that this will be part of a HTTP GET request.  This relates to the fact that we are using a new WCF 3.5 binding called the WebHttpBinding.  This is the same binding used by JSON and POX services.  There are actually a few new attributes, each of which provides it's own treasure chest (see later in this post when I mention a free chapter on the topic).  The WebGet attribute has an awesome property on it called UriTemplate that allows you to match parameters in the request URI to parameters in the WCF operation contract.  That's beyond cool.

The service implementation is extremely straight forward.  All you have to do is create a SyndicationFeed object, populate it with SyndicationItem objects and return it in the constructor of the Rss20FeedFormatter.  Here's a non-Squid example:

SyndicationFeed feed = new SyndicationFeed();
feed.Title = new TextSyndicationContent("My Title");
feed.Description = new TextSyndicationContent("My Desc");
List<SyndicationItem> items = new List<SyndicationItem>();
items.Add(new SyndicationItem()
{
    Title = new TextSyndicationContent("My Entry"),
    Summary = new TextSyndicationContent("My Summary"),
    PublishDate = new DateTimeOffset(DateTime.Now)
});
feed.Items = items;
//+
return new Rss20FeedFormatter(feed);

You may want to make note that you can create an RSS or ATOM feed directly from an SyndicationFeed instance using the SaveAsRss20 and SaveAsAtom10 methods.

As with any WCF service, you need a place to host it and you need to configure it.  To create a service, I simply throw down a FeedService.svc file with the following page directive (I'm really not trying to have the ugliest color scheme in the world-- it's just an added bonus):

<%@ ServiceHost Service="Squid.Service.SquidService" %>

The configuration is also fairly straight forward, all we have is our previously mentioned ending with an address(blank to use FeedService.svc directly), binding (WebHttpBinding), and contract(Squid.Service.ISquidService).  However, you also need to remember to add the WebHttp behavior or else nothing will work for you.

<system.serviceModel>
  <behaviors>
    <endpointBehaviors>
      <behavior name="FeedEndpointBehavior">
        <webHttp/>
      </behavior>
    </endpointBehaviors>
  </behaviors>
  <services>
    <service name="Squid.Service.SquidService">
      <endpoint address=""
                binding="webHttpBinding"
                contract="Squid.Service.ISquidService"
                behaviorConfiguration="FeedEndpointBehavior"/>
    </service>
  </services>
</system.serviceModel>

That's seriously all there is to it: write your contract, write your implementation, create a host, and set configuration.  In other words, creating a syndication feed in WCF is no different than creating a WsHttpBinding or NetTcpBinding service.  However, what about reading an RSS or ATOM feed? This is even simpler.

To read a feed all you have to do is create an XML reader with the data source of the feed and pass that off to the static Load method of the SyndicationFeed class.  This will return an instance of SyndicationFeed which you may iterate or, as I'm doing in Squid, transform with LINQ.  I actually liked how my server-control used an internal repeater instance and therefore wanted to continue to use it.  So, I kept my ITemplate object (RssListTemplate) the same and used the following LINQ to transform a SyndicationFeed to what my ITemplate what already using:

Object bindingSource = from entry in feed.Items
                       select new SimpleFeedEntry
                       {
                           DateTime = entry.PublishDate.DateTime,
                           Link = entry.Links.First().Uri.AbsoluteUri,
                           Text = entry.Content != null ? entry.Content.ToString() : entry.Summary.Text,
                           Title = entry.Title.Text
                       };

Thus, with .NET 3.5 I was able to remove RSS.NET and ATOM.NET completely from the project.  LINQ also, of course helped me with my database access and therefore remove my dependency on my LLBLGen Pro generated DAL:

using (DataContext db = new DataContext(Configuration.DatabaseConnectionString))
{
    var collection = from p in db.FeedCreations
                     where p.FeedCreationTitle == title
                     select p;
    //+ More code here
}

Thus, you can use Squid in your existing .NET 3.5 system with little impact to anything.  Squid is what I use in my Minima blog engine to provide the boxes of information in the sidebar.  I'm able to modify the data in the Snippet table in the Squid database to modify the content and order in my sidebar.  Of course I can also easily bring in RSS/ATOM content from the web with this as well.

You can get more information on the new web support in WCF 3.5 by reading the chapter "Programmable Web" (free chapter) in the book Essential WCF for .NET 3.5 (click to buy).  This is an amazing book that I highly recommend to all WCF users.

Links

NetFXHarmonics DevServer Released



Two months ago started work on a project to help me in my AJAX and SOA development.  What I basically needed was a development web server that allowed me to start up multiple web servers at once, monitor server traffic, and bind to specific IP interfaces.  Thus, the creation of NetFXHarmonics DevServer.  I built it completely for myself, but others started to ask for it as well.  When the demand for it became stronger, I realized that I needed to release the project on the web.  Normally I would host it myself, but given the interest from the .NET community, I thought I would put it on CodePlex.  I've only cried twice seen I've put it on CodePlex, but I'll survive.

NetFXHarmonics DevServer is a web server hosting environment built on WPF and WCF technologies that allows multiple instances of Cassini-like web servers to run in parallel. DevServer also includes tracing capabilities for monitoring requests and responses, request filtering, automatic ViewState and ControlState parsing, visually enhanced HTTP status codes, IP binding modes for both local-only as well as remote access, and easy to use XML configuration.

Using this development server, I am able to simultaneously start multiple web sites to very quickly view everything that happens over the wire and therefore easily debug JSON and SOAP messages flying back and forth between client and server and between services.  This tool have been a tremendous help for me in the past few months to discover exactly why my services are tripping out without having to enable WCF tracing.  It's also been a tremendous help in managing my own web development server instances for all my projects, each having 3-5 web sites (or segregated service endpoints) each.

Let me give you a quick run down of the various features in NetFXHarmonics DevServer with a little discussion of each feature's usage:

XML Configuration

NetFXHarmonics DevServer has various projects (and therefore assemblies) with the primary being DevServer.Client, the client application which houses the application's configuration.

In the app.config of DevServer.Client, you have a structure that looks something like the following:

<jampad.devServer>
</jampad.devServer>

This is where all your configuration lives and the various parts of this will be explained in their appropriate contexts in the discussions that follow.

Multiple Web Site Hosting

In side of the jampad.devServer configuration section in the app.config file, there is a branch called <servers /> which allows you to declare the various web servers you would like to load.  This is all that's required to configure servers.  Each server requires a friendly name, a port, a virtual path, and the physical path.  Given this information, DevServer will know how to load your particular servers.

<servers>
  <server key="SampleWS1" name="Sample Website 1" port="2001"
          virtualPath="/" physicalPath="C:\Project\DevServer\SampleWebsite1">
  </server>
  <server key="SampleWS2" name="Sample Website 2" disabled="true" port="2003"
          virtualPath="/" physicalPath="C:\Project\DevServer\SampleWebsite2">
  </server>
</servers>

If you want to disable a specific server from loading, use the "disabled" attribute.  All disabled servers will be completely skipped in the loading process.  On the other hand, if you would like to load a single server, you can actually do this from the command line by setting a server key on the <server /> element and by accessing it via a command line argument:

DevServer.Client.exe -serverKey:SampleWS1

In most scenarios you will probably want to load various sets of servers at once.  This is especially true in properly architected service-oriented solutions.  Thus, DevServer includes a concept of startup profiles.  Each profile will include links to a number of keyed servers.  You configure these startup profiles in the <startupProfiles /> section.

<startupProfiles activeProfile="Sample">
  <profile name="Sample">
    <server key="SampleWS1" />
    <server key="SampleWS2" />
  </profile>
</startupProfiles>

This configuration block lives parallel to the <servers /> block and the inclusion of servers should be fairly self-explanatory.  When DevServer starts it will load the profile in the "activeProfile" attribute.  If the activeProfile block is missing, it will be ignored.  If the activeProfile states a profile that does not exist, DevServer will not load.  When using a startup profile, the "disabled" attribute on each server instance is ignored.  That attribute is only for non-startup profile usage.  An activeProfile may also be set via command line:

DevServer.Client.exe -activeProfile:Sample

This will override any setting in the activeProfile attribute of <startupProfiles/>.  In fact, the "serverKey" command line argument overrides the activeProfile <startupProfiles /> attribute as well.  Therefore, the order of priority is is as follows: command line argument override profile configuration and profile configuration overrides the "disabled" attribute.

Most developers don't work on one project and with only client.  Or, even if they do, they surely have their own projects as well.  Therefore, you may have even more servers in your configuration:

<server key="ABCCorpMainWS" name="Main Website" port="7001"
        virtualPath="/" physicalPath="C:\Project\ABCCorp\Website">
</server>
<server key="ABCCorpKBService" name="KB Service" port="7003"
        virtualPath="/" physicalPath="C:\Project\ABCCorp\KnowledgeBaseService">
</server>
<server key="ABCCorpProductService" name="Product Service" port="7005"
        virtualPath="/" physicalPath="C:\Project\ABCCorp\ProductService">
</server>

These would be grouped together in their own profile with the activeProfile set to that profile.

<startupProfiles activeProfile="ABCCorp">
  <profile name="ABCCorp">
    <server key="ABCCorpMainWS" />
    <server key="ABCCorpKBService" />
    <server key="ABCCorpProductService" />
  </profile>
  <profile name="Sample">
    <server key="SampleWS1" />
    <server key="SampleWS2" />
  </profile>
</startupProfiles>

What about loading servers from different profiles?  Well, think about it... that's a different profile:

<startupProfiles activeProfile="ABCCorpWithSampleWS1">
  <profile name="ABCCorpWithSampleWS1">
    <server key="SampleWS1" />
    <server key="ABCCorpMainWS" />
    <server key="ABCCorpKBService" />
    <server key="ABCCorpProductService" />
  </profile>
</startupProfiles>

One of the original purposes of DevServer was to allow remote non-IIS access to development web sites.  Therefore, in DevServer you can use the <binding /> configuration element to set either "loopback" (or "localhost") to only allow access to your machine, "any" to allow web access from all addresses, or you can specific a specific IP address to bind the web server to a single IP address so that only systems with access to that IP on that interface can access the web site.

In the following example the first web site is only accessible by the local machine and the second is accessible by others.  This comes in handy for both testing in a virtual machine as well as quickly doing demos.  If your evil project manager (forgive the redundancy) wants to see something, bring the web site up on all interface and he can poke around from his desk and then have all his complains and irrational demands ready when he comes to your desk (maybe you want to keep this feature secret).

<server key="SampleWS1" name="Sample Website 1" port="2001"
        virtualPath="/" physicalPath="C:\Project\DevServer\SampleWebsite1">
  <binding address="loopback" />
</server>
<server key="SampleWS2" name="Sample Website 2" port="2003"
        virtualPath="/" physicalPath="C:\Project\DevServer\SampleWebsite2">
  <binding address="any" />
</server>

Web Site Settings

In addition to server configuration, there is also a bit of general configuration that apply to all instances.  As you can see from the following example, you can add default documents to the existing defaults and you can also setup content type mappings.  A few content types already exist, but you can override as the example shows.  In this example, where ".js" is normally sent as text/javascript, you can override it to go to "application/x-javascript" or to something else.

<webServer>
  <defaultDocuments>
    <add name="index.jsx" />
  </defaultDocuments>
  <contentTypeMappings>
    <add extension=".jsx" type="application/x-javascript" />
    <add extension=".js" type="application/x-javascript" override="true" />
  </contentTypeMappings>
</webServer>

Request/Response Tracing

One of the core features of DevServer is the ability to do tracing on the traffic in each server.  Tracing is enabled by adding a <requestTracing /> configuration element to a server and setting the "enabled" attribute to true.

<server key="SampleWS1" name="Sample Website 1" port="2001"
        virtualPath="/" physicalPath="C:\Project\DevServer\SampleWebsite1">
  <binding address="loopback" />
  <requestTracing enabled="true" enableVerboseTypeTracing="false" enableFaviconTracing="true" />
</server>

This will have request/response messages show up in DevServer which will allow you to view status code, date/time, URL, POST data (if any), response data, request headers, response headers, as well as parsed ViewState and Control state for both the request and response.  In addition, each entry is color coded based on it's status code.  Different colors will show for 301/302, 500+, and 404.

image

When working with the web, you don't always want to see every little thing that happens all the time.  Therefore, by default, you only trace common text specific file like HTML, CSS, JavaScript, JSON, XAML, Text, and SOAP and their content.  If you want to trace images and other things going across, then set "enableVerboseTypeTracing" to true.  However, since there is no need to see the big blob image data, the data of binary types are not sent to the trace viewer even with enableVerboseTypeTracing.  You can also toggle both tracing as well as verbose type tracing on each server as each is running.

There's also the ability to view custom content types without seeing all the images and extra types.  This is the purpose of the <allowedConntetTypes /> configuration block under <requestTracing />, which is parallel to <servers />.

<requestTracing>
  <allowedContentTypes>
    <add value="application/x-custom-type" />
  </allowedContentTypes>
</requestTracing>

In this case, responses of content-type "application/x-custom-type" are also traced without needing to turn on verbose type tracing.

However, there is another way to control this information.  If you want to see all requests, but want the runtime ability to see various content types, then you can use a client-side filter in the request/response list.  In the box immediately above the request/response list, you can type something like the following:

verb:POST;statuscode:200;file:css;contentType:text/css

Filtering will occur as you type, allowing you to find the particular request you are looking for.  The filter is NOT case sensitive.  You can also clear the request/response list with the clear button.  There is also the ability to copy/paste the particular headers that you want from the headers list by using typical SHIFT (for range) and CTRL-clicking (for single choosing).

Request/Response monitoring actually goes a bit further by automatically parsing both ViewState and ControlState for both request (POST) and response data.  Thanks goes to Fritz Onion for granting me permission to use his ViewState parser class in DevServer.

As a Training Tool

When announce any major project I always provide an "as a training tool" section to explain how the project can be used for personal training.  NetFXHarmonics DevServer is built using .NET 3.5 and relies heavily on LINQ and WCF with a WPF interface.  It also uses extensive .NET custom configuration for all server configuration.  In terms of LINQ, you can find many examples of how to use both query expression syntax and extension method syntax.  When people first learn LINQ, they think that LINQ is an O/R mapper.  Well, it's not (and probably shouldn't be usef for that in enterprise applications! there is only one enterprise class O/R mapper: LLBLGen Pro).  LINQ allows Language INtegrated Query in both C# and VB.  So, in DevServer, you will see heavy reliance on LINQ to search List<T> objects and also to transform LINQ database entities to WCF DTOs.

DevServer also relies heavily on WCF for all inner-process communication via named-pipes.  The web servers are actually hosted inside of a WCF service, thus segregating the web server loader from the client application in a very SOA friendly manner.  The client application loads the service and then acts as a client to the service calling on it to start, stop, and kill server instances.  WCF is also used to communicate the HTTP requests inside the web server back to the client, which is itself a WCF service to which the HTTP request is a client.  Therefore, DevServer is an example of how you can use WCF to communicate between AppDomains.

The entire interface in DevServer is a WPF application that relies heavy on WPF binding for all visual information.  All status information is in a collection to which WPF binds.  Not only that all, but all request/response information is also in a collection.  WPF simply binds to the data.  Using WPF, no eventhandling was required to say "on a click event, obtain SelectedIndex, pull data, then text these TextBox instances".  In WPF, you simply have normal every day data and WPF controls bind directly to that data being automatically updated via special interfaces (i.e INotifyPropertyChanged and INotifyCollectionChanged) or the special generic ObservableCollection<T>.

Since the bindings are completely automated, there also needs to be ways to "transform" data.  For example, in the TabItem header I have a little green or red icon showing the status of that particular web server instance.  There was no need to handle this manually.  There is already a property on my web server instance that has a status.  All I need to do is bind the image to my status enumeration and set a TypeConverter which transforms the enumeration value to a specific icon.  When the enumeration is set to Started, the icon is green, when it says "Stopped", the icon is red.  No events are required and the only code required for this scenario is the quick creation of a TypeConverter.

Therefore, DevServer is an example of WPF databinding.  I've heard people say that they are more into architecture and WCF and therefore have no interested in learning WPF.  This statement makes no sense.  If you don't want to mess with UI stuff, you need to learn WPF.  Instead of handing events all over the place and manually setting data, you can do whatever it is you do and have WPF just bind to your data.  When it comes to creating quick client applications, WPF is a much more productive platform than Windows Forms... or even the web!

Links

NetFXHarmonics on CodePlex



Well, I finally broke down.  My public projects are now freely available for download on CodePlex.  Below is a list of the current projects on CodePlex

Here are the current projects on CodePlex:

As far as creating "releases", these are shared-source/open-source projects and in the model I'm following "releases" are always going to be obsolete.  Therefore, I will provide ZIP versions of the archived major revisions of a project and the current revision will always be available as source code.  The only exception to this may be DevServer, which I may do monthly releases or releases based upon major upgrades.  I'm currently working on new major revisions for a few other projects and when they are completed, I will then post them on to CodePlex as well.

As a reminder, my projects are always architected to follow the current best-practices and idiots for a particular technology and are therefore often fully re-architected based on the current technology.  The reason I do this is for the simple reason that my core specialty is training (technology or not) and that's the driving principle in my projects.  Therefore, on each of my projects there is a "As a Training Tool" section that will explain that projects technology and architecture as well as what else you might be able to learn from it.

As a final note, SVNBridge is working OK for me and has really helped me get over the CodePlex hurdle.  Scott Hanselman was kind enough to encourage me to try SVNBridge again.  I'm honesty glad I did.  The Team System 2008 Team Explorer client which integrated into Visual Studio works every now and again, but I got absolutely sick of everything locking up every time I would save a file.  Not even a check it!  A simple local save!  How people put up with "connected" version control systems is beyond me.  Do people not realize that Subversion does locking too?  Anyways, SVNBridge works great for both check outs and commits (we don't "check in" in the Subversion world-- we use transactional terminology).  If you want Visual Studio 2008 integration AND speed and power and flexibility with CodePlex, get VisualSVN.  It's an add-on for VS2008 that uses Tortoise behind the scenes.  With that, depending on my mood I can commit in both VS2008 (what I would do when working on refactoring or something) and in the Windows shell (what I would do when working with JavaScript files in the world's best JavaScript IDE: Notepad2).