T4 Scaffolding - Powershell Script - t4

Question

I am working on T4Scaffolding, i am using model to generate code, the thing is that the model, thats is POCO for DB, it must have a defined primary key else my code fails,
Here is my command
Scaffold MyScaffolder smArtistDetails -Force
Here is the .ps1 script
[T4Scaffolding.Scaffolder(Description = "Enter a description of ExtMapping here")][CmdletBinding()]
param(
[parameter(Mandatory = $true, ValueFromPipelineByPropertyName = $true)]
[string]$ModelType,
[string]$Project,
[string]$CodeLanguage,
[string[]]$TemplateFolders,
[switch]$Force = $false
)
$mynamespace = "Sma"
$projectFor = $mynamespace + ".Infrastructure.Data"
$namespace = $projectFor # (Get-Project $projectFor).Properties.Item("DefaultNamespace").Value
$outputPath = "Mapping\" + $ModelType
Write-Host "Scaffolding $ModelType ExtMapping..."
$useModelFromProject = $mynamespace + ".Domain"
# get the modelType object from the name
$foundModelType = Get-ProjectType $ModelType -Project $useModelFromProject -BlockUi
$primaryKey = Get-PrimaryKey $ModelType -Project $useModelFromProject
$modelOutputPath = "Mapping\" + $ModelType + "Map"
Add-ProjectItemViaTemplate $modelOutputPath -Template ExtMapping `
-Model #{
Namespace = $namespace;
ModelType = [MarshalByRefObject]$foundModelType;
PrimaryKey = $primaryKey;
EntityName = $ModelType } `
-SuccessMessage "Added ExtMapping output at $projectFor" `
-TemplateFolders $TemplateFolders -Project $projectFor -CodeLanguage $CodeLanguage -Force:$Force
and here is my 74 template code
<## Template Language="C#" HostSpecific="True" Inherits="DynamicTransform" #>
<## Output Extension="cs" #>
<## import namespace="System.Collections" #>
<## import namespace="System.Collections.Generic" #>
<## import namespace="System" #>
<## import namespace="EnvDTE" #>
<## assembly name="System.ComponentModel.DataAnnotations" #>
<## assembly name="System.Core" #>
<## assembly name="System.Data.Entity" #>
<## assembly name="System.Data.Linq" #>
<## import namespace="System.Data.Linq.Mapping" #>
<## import namespace="System.Linq" #>
<## import namespace="System.Collections.Generic" #>
<## import namespace="System.Data.Objects.DataClasses" #>
<## import namespace="System.Reflection" #>
<## import namespace="System.Collections" #>
<## import namespace="System.Text.RegularExpressions" #>
using System;
using System.Collections.Generic;
using System.Text;
using FluentNHibernate.Mapping;
using Sma.Domain.Model;
<#
var modelType = (CodeType)Model.ModelType;
var modelName = modelType.Name;
var properties = modelType.VisibleMembers().OfType<CodeProperty>();
var primaryKeyProperty = modelType.VisibleMembers().OfType<CodeProperty>().Single(x => x.Name == Model.PrimaryKey);
#>
namespace <#= Model.Namespace #>.Mapping
{
public class <#= Model.EntityName #>Map : ClassMap<<#= Model.EntityName #>>
{
public <#= Model.EntityName #>Map() {
Table("<#= Model.EntityName #>");
LazyLoad();
<# var type = "";
var typeName = "";
foreach (var property in properties)
{
type = GetType(property.Type);
typeName = GetTypeName(property.Type);
if( isType(type) )
{
if( Model.PrimaryKey == property.Name )
{
#>
Id(x => x.<#= property.Name #>).GeneratedBy.Identity().Column("<#= property.Name #>");
<#
}
else
{
#>
Map(x=>x.<#= property.Name #>).Column("<#= property.Name #>");
<#}
}
else
{
#>
References(x=>x.<#= property.Name #>);
<#
}
}
#> }
}
}
<#+
string GetType(EnvDTE.CodeTypeRef type)
{
string str = "";
if (type.UnderlyingTypeIs<byte>())
str = "byte";
else if (type.UnderlyingTypeIs<sbyte>())
str = "sbyte";
else if (type.UnderlyingTypeIs<int>())
str = "int";
else if (type.UnderlyingTypeIs<uint>())
str = "uint";
else if (type.UnderlyingTypeIs<short>())
str = "short";
else if (type.UnderlyingTypeIs<ushort>())
str = "ushort";
else if (type.UnderlyingTypeIs<DateTime>())
str = "DateTime";
else if (type.UnderlyingTypeIs<long>())
str = "long";
else if (type.UnderlyingTypeIs<ulong>())
str = "ulong";
else if (type.UnderlyingTypeIs<double>())
str = "double";
else if (type.UnderlyingTypeIs<bool>())
str = "bool";
else if (type.UnderlyingTypeIs<string>())
str = "string";
else if (type.UnderlyingTypeIs<decimal>())
str = "decimal";
else
str = type.AsFullName.ToString();
return str;
}
string GetTypeName(EnvDTE.CodeTypeRef type)
{
string str = type.AsFullName.ToString();
return str;
}
bool isType(string _type)
{
if( _type == "byte" ) return true;
else if( _type == "sbyte" ) return true;
else if( _type == "int" ) return true;
else if( _type == "uint" ) return true;
else if( _type == "short" ) return true;
else if( _type == "ushort" ) return true;
else if( _type == "DateTime" ) return true;
else if( _type == "long" ) return true;
else if( _type == "ulong" ) return true;
else if( _type == "double" ) return true;
else if( _type == "bool" ) return true;
else if( _type == "string" ) return true;
else if( _type == "decimal" ) return true;
return false;
}
#>
what to do.. If the primary key is not found i want to follow a different output\genration method.
Should i switch from script to a different template, if yes then How
or Should i handle this in this template, if yes then how.

Answer 1

I would check if the PK was found in the PS, and if not call another template... Personally I would force all the classes in the model to inherit a abstract base class that already has a primary key. That way this will never be an issue. But then again, your purpose might be something I do not know of...