Modernize SampleMvcWebApp to cross-platform .NET 8 (ASP.NET Core MVC + EF Core 8)

[devin-ai-integration]

Summary

Migrates the app from ASP.NET MVC 5 / .NET Framework 4.5.1 to cross-platform ASP.NET Core MVC on .NET 8, preserving all pages, CRUD flows, and business rules. Every project is now SDK-style net8.0; System.Web, Global.asax, web.config, packages.config, Autofac, and log4net are gone. The solution builds clean (0 warnings) and a net8.0 NUnit 4 suite (17 tests) passes.

The app depends on the GenericServices framework, which is EF6-only with no .NET 8 build. Rather than rewrite every DTO/controller onto a different framework (behavior-risky), this PR ports the exact GenericServices/GenericLibsBase API surface the app uses into two small in-repo net8.0 libraries backed by EF Core 8 + AutoMapper 14, so DTOs and controller call-sites stay essentially unchanged.

Architecture: MVC5 → ASP.NET Core MVC

• Global.asax + App_Start/* (Route/Bundle/Filter config) → Program.cs (middleware, routing, DI, DB init).
• Autofac + custom DiModelBinder (which enabled action-parameter service injection like Index(IListService service)) → built-in DI. To keep the original controller signatures unchanged, a small ServiceParameterBindingConvention marks action parameters whose type is a registered service as BindingSource.Services:

  // Program.cs
  builder.Services.AddSingleton<IConfigureOptions<MvcOptions>, ConfigureServiceParameterBinding>();
  // convention: if IServiceProviderIsService.IsService(param.Type) -> BindingSource.Services

• MVC5 bundling (@Styles.Render/@Scripts.Render) → static <link>/<script> tags served from wwwroot/ (Content, Scripts, fonts moved there).
• MvcHtmlString error HTML in TempData["errorMessage"] → plain string rendered with @Html.Raw(...) (identical output).
• log4net → Microsoft.Extensions.Logging via a MelGenericLogger : IGenericLogger bridge wired through GenericLibsBaseConfig.
• InternalsInfo Windows-only PerformanceCounter → cross-platform GC.GetGCMemoryInfo().
• web.config/Settings → appsettings.json (connection string + HostTypeString).

Architecture: EF6 → EF Core 8

• SampleWebAppDb is now an EF Core DbContext implementing IGenericServicesDbContext + IValidateOnSave; default provider is SQLite (Data Source=SampleWebAppDb.db) for cross-platform demo use.
• Data model preserved: Blog, Post, Tag, Post.BlogId, many-to-many Post/Tag, LastUpdated stamping, XML seed loading, and small/medium reset semantics. Initial EF Core migration added under DataLayer/Migrations.
• EF6 DbContext.ValidateEntity (no EF Core equivalent) → IValidateOnSave.ValidateEntity, invoked by the ported SaveChangesWithChecking, preserving the unique-tag-slug rule and error text.
• GenericServices "write" maps: instead of AutoMapper cloning DTO→entity (which would clone/recurse tracked navigations like the chosen Tags), a reflection copier (EntityFromDto) copies scalars and assigns navigations by reference so EF Core tracks them; AutoMapper is used only for entity→DTO reads/projections (ProjectTo).

Changed dependencies (and why)

• AutoMapper 14.0.0 — last MIT-licensed line (15+ is commercial). A single scoped NuGetAuditSuppress for GHSA-rvv3-g6hj-g44x is applied and documented; no security setting was weakened.
• EF Core 8 (Microsoft.EntityFrameworkCore.Sqlite/.Design 8.0.11), built-in DI, Microsoft.Extensions.Logging.
• Tests: NUnit 4.2.2 + NUnit3TestAdapter + Microsoft.NET.Test.Sdk, EF Core SQLite in-memory.

Test evidence

• dotnet build SampleWebApp.sln → 0 warnings, 0 errors (Debug + Release).
• dotnet test SampleWebApp.sln → 17 passed, 0 failed.
• Ran the app (dotnet run --project SampleWebApp): DB auto-migrates + seeds; verified 200 for Home, Posts/Tags/Blogs (sync + async), Details, Edit, Create, Internals, CodeView, Delay. Verified a full write path via HTTP with antiforgery token: create Tag → 302 + appears in list; duplicate slug → validation error rendered.
• New regression tests cover: XML seed counts, many-to-many + blogger load, LastUpdated stamping, list projections/flattening (PostsCount, BloggerName, Tags), detail/edit setup pickers, update (title + tag replacement), create with tags, delete, async detail/create, and business-rule rejections (no blogger, no tags, ! title, duplicate slug).

Remaining risks

• Default DB provider changed to SQLite (was SQL Server LocalDB); production SQL Server compatibility not re-validated.
• EF Core validation/tracking/cascade behavior can differ subtly from EF6.
• AutoMapper pinned to 14.0.0 with a scoped audit suppression (see above).
• The legacy test suite asserted EF6/Autofac/MVC5 internals that no longer exist; it was replaced with focused regression tests for the preserved behavior rather than ported 1:1.

Human-review checklist

• Confirm SQLite is acceptable as the demo provider (or swap the UseSqlite call + connection string for SQL Server).
• Review EntityFromDto navigation-by-reference copy vs. the original AutoMapper write behavior.
• Review ServiceParameterBindingConvention as the replacement for the MVC5 DiModelBinder.
• Accept the AutoMapper 14 pin + GHSA-rvv3-g6hj-g44x suppression.
• Spot-check the new regression tests are meaningful for your acceptance criteria.

Rollback guidance

Single-branch change with no data migration of existing stores (new local SQLite file is created on first run). To roll back, revert the merge commit / redeploy the previous build; delete the generated SampleWebAppDb.db if present. No external infrastructure was modified.

Link to Devin session: https://app.devin.ai/sessions/96f873d8bcf34290ab2609be7b941738
Requested by: @achalc

---

Devin Review

Status	Commit
⚪ Not started	—

Run Devin Review

[devin-ai-integration]

🤖 Devin AI Engineer

I'll be helping with this pull request! Here's what you should know:

✅ I will automatically:

• Address comments on this PR. Add '(aside)' to your comment to have me ignore it.
• Look at CI failures and help fix them

Note: I can only respond to comments from users who have write access to this repository.

⚙️ Control Options:

• Disable automatic comment, CI, and merge conflict monitoring