Allow new partial templates to be regisgered.

Thanks to @omatrot, @gejotas, @TryAndErr0r (Mehmke Adrian), Gert-Jan ter Schure.

Author: tonysneed

README.md

@@ -70,6 +70,16 @@ Before creating a pull request, please refer to the [Contributing Guidelines](ht
     specific interfaces.
     - When you run the _dotnet-ef-dbcontext-scaffold_ command again, you will see your updated reflected in the generated classes.
 
+## Additional Partial Templates
+
+You can add new partial templates to one of the `Partials` folders, then reference with the usual Handlebars syntax. For example, a file named **Comment.hbs** can be referenced from **Class.hbs**.
+
+```hbs
+{{{> comment}}}
+public class {{class}}
+{
+```
+
 ## Excluded Tables
 
 You can optionally exclude certain tables from code generation. These may also be qualified by schema name.

sample/ScaffoldingSample.TypeScript/CodeTemplates/TypeScriptDbContext/DbContext.hbs

@@ -0,0 +1,21 @@
+{{> dbimports}}
+
+namespace {{namespace}}
+{ // Comment
+    public partial class {{class}} : DbContext
+    {
+{{{> dbsets}}}
+{{#if entity-type-errors}}
+{{#each entity-type-errors}}
+{{spaces 8}}{{{entity-type-error}}}
+{{/each}}
+
+{{/if}}
+
+{{{> dbconstructor}}}
+
+{{{> dbonconfiguring}}}
+
+{{{on-model-creating}}}
+    }
+}

sample/ScaffoldingSample.TypeScript/CodeTemplates/TypeScriptDbContext/Partials/DbOnConfiguring.hbs

@@ -0,0 +1,10 @@
+{{spaces 8}}protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+{{spaces 8}}{
+{{spaces 12}}if (!optionsBuilder.IsConfigured)
+{{spaces 12}}{
+{{#if suppress-connectionstring-warning}}
+{{spaces 16}}{{sensitive-information-warning}}
+{{/if}}
+{{spaces 16}}optionsBuilder{{options-builder-provider}};
+{{spaces 11}} }
+{{spaces 7}} }

sample/ScaffoldingSample.TypeScript/ScaffoldingSample.TypeScript.csproj

@@ -7,10 +7,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="3.1.0" />
-    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.0">
-      <PrivateAssets>all</PrivateAssets>
-      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
-    </PackageReference>
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.0" />
   </ItemGroup>
 
   <ItemGroup>

sample/ScaffoldingSample/CodeTemplates/CSharpDbContext/DbContext.hbs

@@ -14,6 +14,8 @@ namespace {{namespace}}
 
 {{{> dbconstructor}}}
 
+{{{> dbonconfiguring}}}
+
 {{{on-model-creating}}}
     }
 }

sample/ScaffoldingSample/CodeTemplates/CSharpDbContext/Partials/DbOnConfiguring.hbs

@@ -0,0 +1 @@
+{{{on-configuring}}}

sample/ScaffoldingSample/CodeTemplates/CSharpEntityType/Class.hbs

@@ -1,7 +1,7 @@
 {{> imports}}
 
 namespace {{namespace}}
-{ // Comment
+{ {{{> comment}}}
 {{#if class-annotation}}
 {{spaces 4}}{{{class-annotation}}}
 {{/if}}

sample/ScaffoldingSample/CodeTemplates/CSharpEntityType/Partials/Comment.hbs

@@ -0,0 +1 @@
+// Comment

sample/ScaffoldingSample/Contexts/NorthwindSlimContext.cs

@@ -26,6 +26,16 @@ public NorthwindSlimContext(DbContextOptions<NorthwindSlimContext> options) : ba
         {
         }
 
+        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+        {
+            if (!optionsBuilder.IsConfigured)
+            {
+#warning To protect potentially sensitive information in your connection string, you should move it out of source code. See http://go.microsoft.com/fwlink/?LinkId=723263 for guidance on storing connection strings.
+                optionsBuilder.UseSqlServer("Data Source=(localdb)\\MSSQLLocalDB; Initial Catalog=NorthwindSlim; Integrated Security=True");
+            }
+        }
+
+
         protected override void OnModelCreating(ModelBuilder modelBuilder)
         {
             modelBuilder.Entity<Category>(entity =>
@@ -37,6 +47,8 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
 
             modelBuilder.Entity<Customer>(entity =>
             {
+                entity.HasComment("hello table Customer");
+
                 entity.Property(e => e.CustomerId)
                     .HasMaxLength(5)
                     .IsFixedLength();
@@ -45,7 +57,8 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
 
                 entity.Property(e => e.CompanyName)
                     .IsRequired()
-                    .HasMaxLength(40);
+                    .HasMaxLength(40)
+                    .HasComment("hello CompanyName");
 
                 entity.Property(e => e.ContactName).HasMaxLength(30);
 

sample/ScaffoldingSample/ScaffoldingDesignTimeServices.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using EntityFrameworkCore.Scaffolding.Handlebars;
 using HandlebarsDotNet;
@@ -19,6 +20,9 @@ public class ScaffoldingDesignTimeServices : IDesignTimeServices
     {
         public void ConfigureDesignTimeServices(IServiceCollection services)
         {
+            // Uncomment to launch JIT debugger and hit breakpoints
+            //Debugger.Launch();
+
             // Add Handlebars scaffolding templates
             services.AddHandlebarsScaffolding(options =>
             {