Making the most of Brownfield Application Development – Winnipeg Edition

On Friday July 23rd I’ll be in Winnipeg giving a one day seminar on the nuances of Brownfield Application Development and how to get the most out of it.  More about the day can be found here.  I recently did the seminar at the PrairieDevCon and it was a blast.  The day is filled chocka-block with content and ideas that pertain directly to Brownfield codebases and will work in Greenfield situations.

Registration can be found here and until July 2nd the session is available at a discount.  Hope to see you there!

Published at

Visual Studio Project files and coupling

The way that we’re told to use Visual Studio is that we create a solution file and add into it one or more project files.  Each project file then gets filled with different development artefacts.  When you build inside of Visual Studio each project represents a compiled distributable file (exe, dll, etc).  Many people carry this practice over into their build scripts.  You might be one of them.  I’m here to tell you why you’re wrong to be doing this.

Let’s say you’re starting a project.  You open Visual Studio, select File | New Project and get things rolling.  In a few minutes you have a Solution that contains a few Projects.  Maybe you have one for the UI, one for the business logic and one for the data access layer.  All is good.  A few months later, after adding many artefacts to the different projects, something triggers the need to split the artefacts into one assembly from one DLL into two DLLs. 

You set off to make this happen.  Obviously you need to add a new Project to your Solution, modify some references, and shift some files from one Project into another.  Say you’re stuck using an exclusive locking source control system (like VSS…shudder).  You *must* have exclusive access to all the files necessary including:

  • the sln so you can add the new project
  • at least one existing cs/vb/fsproj which you’ll be removing existing code artefacts from
  • any cs/vb/fs files that will be moved
  • any cs/vb/fs files that reference the ones moving (using statements will need updating when you change the namespacing on the files being moved)
  • possibly some resx files that need to be moved
  • possibly config files that need to be changed or moved
  • any automated tests that make use of the moving cs/vb/fs files

It’s a pretty damn big list of files that you will need to exclusively lock during this process.  Chances are you will need to push all of your co-workers out of the development environment so that you can gain access to all of those files.  Essentially you are, at this point, halting the development process so that you can do nothing more than split one DLL into two.  That in quite inefficient in the short term and it’s completely unsustainable in the long term.

I can hear you now, “Well I use <git/mercurial/svn/etc> so we won’t have those issues”.  Really?  Think it through for a second.  Go ahead, I’ll wait.

With the volume of changes that I listed above, you’ll likely want to be working in some kind of isolation, whether that is local or central.  So yes, you can protect yourself from blocking the ongoing development of your co-workers by properly using those version control systems.  But remember, you do have to integrate your changes with their work at some point.  How are you going to do that?  You’ve moved and modified a significant number of files.  You will have to merge your changes into a branch (or the trunk) locally or otherwise.  Trust me, this will be a merge conflict nightmare.  And it won’t be a pain just for you.  What about the co-worker that has local changes outstanding when you commit your merged modification?  They’re going to end up with a massive piece of merge work on their plate as well.  So instead of being blocked while you do the work, you’re actually creating a block for them immediately after you have completed your work.  Again, the easiest way to achieve the changes would be to prevent any other developers from working in the code while modifications are occurring.  Doesn’t that sound an awful lot like exclusive locking?

Now, I know you’re thinking “Pfft..that doesn’t happen often”.  This is where you’re wrong.  When you started that application development cycle (remember File | New Project?) you likely didn’t have all of the information necessary to determine what your deployables requirements were.  Since you didn’t have all of that information, chances were good, right from the outset, that you were going to be doing the wrong thing.  With that being the case, it means that chances were good that you were going to have to make changes like the one described above.  To me that indicates that you are, by deciding to tie your Visual Studio Projects to your deployables, accepting that you will undertake this overhead.

People, possibly you, accept this overhead on every software project they participate in.  This is where you’re wrong.  There is a way to avoid all of this, but people shrug it off as “not mainstream” and “colouring outside the lines”.  The thing is it works, so ignore it at your own peril.

There is a lot of talk in some development circles about decoupling code.  It’s generally accepted that tightly coupled code is harder to modify, extend and maintain.  When you say that a Visual Studio Project is the equivalent of a deployable, you have tightly coupled your deployment and development structures.  Like code, and as the example above shows, it makes it hard to modify, extend and maintain your deployment.  So why not decouple the Visual Studio Project structure from the deployables requirements?

It’s not that hard to do.  You’ll need to write a build script that doesn’t reference the cs/vb/fsproj files at all.  The .NET Framework kindly provides configurable compiler access for us.  The different language command line compilers (vbc.exe/csc.exe/fsc.exe) allow you to pass in code files, references, resources, etc.  By using this capability, you can build any number of assemblies that you want simply by passing a listing of artefacts into the compiler.  To make it even easier, most build scripting tools provide built in capability to do this.  NAnt and MSBuild both provide (for C#) <csc> tasks that can accept wild carded lists of code files.  This means you can end up with something like this coming out of a solution-project structure that has only one project in it:

<csc output="MyApp.DAL.dll" target="library" debug="${debug}">
  <sources>
    <include name="MyApp.Core/DAL/**/*.cs"/>
  </sources>
  <references>
    <include name="log4net.dll"/>
  </references>
</csc>

<csc output="MyApp.Core.dll" target="library" debug="${debug}">
  <sources>
    <include name="MyApp.Core/Business/**/*.cs"/>
  </sources>
  <references>
    <include name="log4net.dll"/>
    <include name="MyApp.DAL.dll"/>
  </references>
</csc>

<csc output="MyApp.UI.exe" target="winexe" debug="${debug}">
  <sources>
    <include name="MyApp.Core/**/*.cs"/>
    <exclude name="MyApp.Core/DAL/*.cs"/>
    <exclude name="MyApp.Core/Business/*.cs"/>
  </sources>
  <references>
    <include name="log4net.dll"/>
    <include name="MyApp.DAL.dll"/>
    <include name="MyApp.Core.dll"/>
  </references>
</csc>

Likewise, we could consolidate code from multiple projects (really file paths is what the build script sees them as) into one deployable.

<csc output="MyApp.UI.exe" target="winexe" debug="${debug}">
  <sources>
    <include name="MyApp.DAL/**/*.cs"/>
    <include name="MyApp.Business/**/*.cs"/>
    <exclude name="MyApp.UI/**/*.cs"/>
  </sources>
  <references>
    <include name="log4net.dll"/>  
  </references>
</csc>

Now, when it comes time to change to meet new deployables needs, you just need to modify your build script.  Modify the inputs for the different compiler calls and/or add new compilations simply by editing one file.  While you’re doing this the rest of your co-workers can continue doing what they need to provide value to the business.  When it comes time for you to commit the changes to how things are getting compiled, you only have to worry about merging one file. Because the build script is far less volatile than the code files in your solution-project structure, that merge should be relatively painless.

Another way to look at this is that we are now able to configure and use Visual Studio and the solution-project structure in a way that is optimal for developers to write and edit code.  And, in turn, we configure and use the build script in a way that allows developers to be efficient and effective at compiling and deploying code.  This is the decoupling that we really should have in our process and ecosystem to allow us to react quickly to change, whether it comes from the business or our own design decisions.

Rotating text using Graphics.DrawString

Recently I needed to create a custom WinForms label-like control that allowed for the text to be displayed in a rotated fashion.  Our needs were only for four rotation locations; 0 degrees (the default label position), 90, 180 and 270 degrees.  There were other complicating factors, but for this post we’ll only concentrate on this component of the control.

To rotate text using the Graphics.DrawString method you only have to do a couple of things.  First you have to use the Graphics.TranslateTransform method, then the Graphics.RotateTransform method, and followed by the Graphics.DrawString.  Here’s what it looks like.

using (var brush = new SolidBrush(ForeColor))
{
    var stringFormat = new StringFormat
                       {
                           Alignment = StringAlignment.Near,
                           LineAlignment = StringAlignment.Near
                       };
    e.Graphics.TranslateTransform(transformCoordinate.X, transformCoordinate.Y);
    e.Graphics.RotateTransform(rotationDegrees);
    e.Graphics.DrawString(Text, Font, brush, DisplayRectangle, stringFormat);
}

What you see are the three steps that I outlined above.  Let’s start at the bottom and work our way up.  The code exists inside of a UserControl’s overridden OnPaint event.  The DrawString method makes use of some of the properties on the control, like Text and Font.  It also uses the DisplayRectangle property to set the boundaries for the drawing to be the same size as the control.  This is one of the keys to making the rotations work.  The other key is to provide the DrawString with the StringFormat settings.  By setting them to be StringAlignment.Near for both the Alignment and LineAlignment, you are declaring that the text’s location should be based in the top left of the DisplayRectangle’s area.

Graphics.RotateTransform is how you set the rotation value.  In the case of our control, we would be putting in a value from the list of 0, 90, 180, and 270.  As you might expect the rotations are clockwise with 0 starting with the text in the ‘normal’ location.

Graphics.TranslateTransform is where the last piece of magic occurs.  It is here that you set where the top right corner of the text drawing area will be located in the DisplayRectangle’s area.  Here are some images that will help clarify the situation.

0degrees

When you need the text to appear the same as “Text Area” does in the above image (rotated 0 degrees), you need to set the TranslateTransform X and Y parameters to be those that are designated by the “X” in the image.  In this case, it’s X=0 and Y = 0.

90degrees

The picture above shows you what you should be displayed when you are rotating the text “Text Area” 90 degrees.  Again, you need to set the TranslateTransform, but this time the values are slightly different.  The Y parameter is still 0, but the X parameter equals the height of the text.  You can get this value by using the following line of code:

var textSize = TextRenderer.MeasureText(Text, Font);
textSize.Height;

180degrees

To render the text upside down we set the rotation to 180 degrees and then, again, determine the location of the TranslateTransform X and Y coordinates.  Like we did for the last rotation, we will need to retrieve the text size to set these values.  For this situation Y will be the text height and X will be the text width.

270degrees

The final step is to make the rotation work for 270 degrees.  Like all the others, we need to set the X and Y coordinates for the TranslateTransform method call.  Here the Y value will be the text width and the X value will be 0.

This is simply the first step of many to making a control that will allow rotation of the text and locating it in one of 9 locations in a 3x3 grid representation of the control’s DisplayRectangle.  More on that in another blog post though.

Published at

Originally posted at

PrairieDevCon 2010 wrapup

Friday past brought the end to the first incarnation of the PrairieDevCon in Regina.  The conference had a great buzz of people, interest, conversations and learning about it.  It really was a blast to be at it.  Thanks to everyone who attended in whatever capacity since it was you that made this event so much fun and productive to be at.

Here are the materials from the sessions that I presented.  There isn’t anything for the panel discussion since it was all off the cuff.  If you weren’t there you didn’t get to add or absorb….sorry.

Intro To Aspect Oriented Programming: Slides, Code
ORM Fundamentals: Slides

Thanks again everyone and I hope to get invited back to do this all again next year.