Thursday, November 13, 2014

Binding redirects at runtime

Hopfully the C# audience can read this F#, but this is how you would do it =)
printfn "starting up"
open System
open System.Reflection

let RedirectAssembly shortName (targetVersion : Version) publicKeyToken = 
    let rec onResolveEvent = new ResolveEventHandler( fun sender evArgs ->
        let requestedAssembly = 
        if requestedAssembly.Name <> shortName 
            printfn "redirect firing for %s" requestedAssembly.Name; Unchecked.defaultof<Assembly>
                "Redirecting assembly load of %s ,\tloaded by %s" 
                (if evArgs.RequestingAssembly = null then 
            requestedAssembly.Version <- targetVersion
            requestedAssembly.SetPublicKeyToken (AssemblyName(sprintf "x, PublicKeyToken=%s" publicKeyToken).GetPublicKeyToken())
            requestedAssembly.CultureInfo <- System.Globalization.CultureInfo.InvariantCulture
            Assembly.Load (requestedAssembly)
// sample usage
RedirectAssembly "FSharp.Core" (Version("")) "b03f5f7f11d50a3a"

Thursday, October 9, 2014

Using a Git layer on top of TFS

Not having git bugs me. Working with any other source control system takes away some of my power.

With a git layer over whatever other source control system is required for the team:

  • I can check-in or revert individual lines of code in a file. 
  • I can create a branch for local modifications that should never be checked into the team source control.
  • I can create mini-commits that don't have to be logged as individual commits in the team source (for teams that prefer one large change-set)
    • I can create my own personal historical record of change save-points and notes/comments
  • I can select which lines of a file should go into a check-in without shelving the entire change.

How to:

Create a junction or hardlink to the folder that contains your code. This junction must not be in the tree that your tfs workspace mapping sees. If it is, Visual Studio will then, forcefully and persistently, use git as your source control and refuse to talk to TFS about your changes.

So I have all my code under c:\development\foo

  1.  I change working directory to c:\projects\bar and mklink /h /j foobar c:\development\foo
  2. git init
  3. Always point visual studio at the legacy folder c:\development\foo.
  4. Always point your git tool(s) at c:\projects\bar
  5. profit!

Monday, June 30, 2014

Why am I so enthusiastic about F#?

I'm suddenly really passionate about F#. This is new as of ~3 weeks ago.

Thursday, April 17, 2014

T4 ApiController Generator

This T4 assumes your DbContext is called ApplicationDbContext in a file called ApplicationDbContext.cs and does not account for whatever custom namespaces need to be imported for this file for your use. It is set up for DI, but lacks consumption of an IRepository pattern or anything similar. It also expects to be in a directory below the EnvDteHelper.ttinclude.
<#@ template debug="false" hostspecific="true" language="C#" #>
<#@ assembly name="System.Core" #>
<#@ assembly name="System.Data.Entity.Design" #>
<#@ import namespace="System.Globalization" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Data.Entity.Design.PluralizationServices" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ output extension=".cs" #>
<# DTE Dte;#>
<#@ include file="../EnvDteHelper.ttinclude"#>
  var suggestedNs=System.Runtime.Remoting.Messaging.CallContext.LogicalGetData("NamespaceHint");
  var projects = RecurseSolutionProjects(Dte);
  var q= from p in projects
      from pi in p.ProjectItems.Cast<ProjectItem>()
      where pi.FileCodeModel!=null
      select new{p,pi,CodeElements=pi.FileCodeModel.CodeElements.Cast<CodeElement>()};
  var context= q.Where(x=>x.pi.Name=="ApplicationDbContext.cs").First();
  var typesToMap = Descendants(context.CodeElements,ce=>ce.Children.Cast<CodeElement>()).OfType<CodeProperty>();
  var project=GetProjectContainingT4File(Dte,false);
  var pluralizationService = PluralizationService.CreateService(new CultureInfo("en-US"));
using System.Linq;
using System.Web.Http.OData;

using Microsoft.AspNet.Identity.EntityFramework;

namespace <#=suggestedNs#>
<#  foreach(var tm in typesToMap){
  var singular=pluralizationService.Singularize(tm.Name);
  var plural=pluralizationService.Pluralize(tm.Name);

    public class <#=tm.Name#>Controller : ODataController
        readonly ApplicationIdentityContext _db;

        public <#=tm.Name#>Controller(ApplicationIdentityContext db)
            _db = db;

        /// GET api/<#=singular#>
        public IQueryable<<#=singular#>> Get()
            return _db.<#=plural#>;

        // GET api/<#=singular#>/5
        public <#=singular#> Get(int id)
            return _db.<#=plural#>.FirstOrDefault(x=>x.<#=singular#>Id==id);


Monday, April 14, 2014

VS2013 negative look-behind on a sql server database project

Find me all the sql tables that have an unnamed foreign key.
Find all "(?>!(CONSTRAINT|--) .*)FOREIGN KEY", Regular expressions, Subfolders, Find Results 1, Current Project: Project.Sql\Project.Sql.sqlproj, "*.SQL"

Wednesday, March 12, 2014

Vs2013 search and replace in html classes

This lovely regex helps pull extra whitespace out of a class attribute. search: class="\s*(\w+)\s+(\s\w+)?\s*" replace: class="$1$2" It only handles up to 2 classes being inside and... I forgot to consider the possibility of having razor inside. However, this shouldn't break that it just won't clean it.

Monday, January 20, 2014

T4 Generating Dummy Adapters

I needed to code up an adapter layer between the domain and the ui. For now, and until something more specific is needed, just expose out the public methods of the domain and their result types. There is more that the adapter is encapsulating but the premise remains.

Added my Nuget packages for code generation: T4EnvDte and T4MultiFile.

As it turns out some of the code that was useful for this operation required a modification of T4EnvDte. So I added an assembly reference to EnvDTE80. This was to finally write usable code to get all the projects in a solution recursing through solution folders.

Let's have a look at the actual T4 line by line, that uses the new code so we can see what is required for this task.
<#@ template debug="True" language="C#" hostspecific="True" #>
<#@ output extension=".txt"#>
<#@ include file="MultipleOutputHelper.ttinclude" #>
<#@ import namespace="EnvDTE"#>
<# EnvDTE.DTE Dte; #>
<#@ include file="EnvDteHelper.ttinclude" #>
<#  bool doMultiFile=true;#>

This is the basic start of the file, with 2 variables declared thus far. Dte and doMultiFile. One is the Visual studio com object, the other is a flag telling T4MultiFile if we want to generated multiple files or all into one.

Main file output
Last run at <#=DateTime.UtcNow.ToString()#>

This simple code is all that is going to the main file output, a simple date/time string for showing when the file was last run. The usefulness is debatable in any proper source controlled scenario.

<# var manager = Manager.Create(Host, GenerationEnvironment);
var targetNs=System.Runtime.Remoting.Messaging.CallContext.LogicalGetData("NamespaceHint"); //1
var projects= RecurseSolutionProjects(Dte); //2
var project = projects.First(p=>p.Name=="Company.Domain"); //3
var toGen= RecurseProjectItems(project).Where(pi=>pi.Name.StartsWith("Org")); //4

foreach(var p in toGen){
  var className=Before(p.Name,".")+"Adapter"; //1
  manager.StartNewFile(className+".generated.cs"); //2
  var fcModel= p.FileCodeModel; //3
  var ns=fcModel.CodeElements.OfType<EnvDTE.CodeNamespace>().First(); //4
  var codeClass= ns.Children.OfType<EnvDTE.CodeClass>().First(); //5
  var codeMethods= codeClass.Children.OfType<EnvDTE.CodeFunction>(); //6

This is all the setup and starting the file per type looping.

  1. targetNs asks what the proper namespace for our current file output location would be
  2. projects gets all the projects in the current solution using the new EnvDte helper code
  3. project the actual project name we are looking for
  4. toGen gets the projectItems in the source project we are interested in
Now we look over those items we will be generating
  1. className holds the name of the new adapter class
  2. tell the helper to start a new file for the class
  3. fcModel holds the FileCodeModel of the current source projectItem
  4. ns holds the namespace that wraps our target class and assumes there is only one namespace in the source file
  5. codeClassholds the reference to the target class and assumes there is only one class in the source file
  6. codeMethods gets all the methods of the source class

the meat of the individual file generation

//<#=p.Name#> <# /* 1 */ #>

using <#= ns.Name#>; <# /* 2 */ #>

namespace <#=targetNs#>{ <# /* 3 */ #>

  public class <#=className#>{ <# /* 4 */ #>
<# foreach (var m in codeMethods.Where(m=>m.Access==EnvDTE.vsCMAccess.vsCMAccessPublic)){ var parms= m.Parameters.OfType<CodeParameter>(); #> <# /* 5-5.1 */ #>
     public <#=  m.Type.AsFullName#> <#=m.Name#>(<#=parms.Any()? parms.Select(parm=>parm.Type.AsString+" "+parm.Name).Aggregate((s1,s2)=>s1+","+s2):string.Empty#>){ <# /* 5.2 */ #>
      return <#=Before(p.Name,".")#>.Instance.<#=m.Name#>(<#=parms.Any()?parms.Select(parm=>parm.Name).Aggregate((s1,s2)=>s1+","+s2):string.Empty#>); <# /* 5.3 */ #>
<#    } #>      
} //end foreach

  1. adds a comment of the source file name
  2. adds a using clause for the source file's namespace
  3. adds a namespace for our new file
  4. adds a class to our new adapter
  5. loop over the public methods in the class
    1. parms holds a reference to the parameters of the method if any
    2. Generate the method signature
    3. Generate the method return code (which includes the singleton-based Instance property requirement of this domain layer
  6. close up the single file generator and the foreach

the last little bits of code that complete the file


string Before(string text, string delimiter)
    return text.Substring(0,text.IndexOf(delimiter,StringComparison.CurrentCulture));

So there we see using T4EnvDte and T4MultiFile together to generate specific classes from another project in the solution. I welcome any and all questions or suggestions for improvement