ApiImplementer 1.0.0

AutoApi

Zero-code CRUD APIs for ASP.NET Core.
Decorate your model with [AutoApi] — get fully working REST endpoints instantly. No controllers. No boilerplate.

Table of Contents

• What is AutoApi?
• Installation
• Quick Start
• Generated Endpoints
• Configuration
  • Route Prefix
  • Custom Route per Model
  • Restrict HTTP Methods
  • Swagger / OpenAPI Tags
  • Scan Multiple Assemblies
• Stores
  • In-Memory Store (default)
  • EF Core Store
  • Custom Store
• Full Example
• FAQ
• Contributing
• License

What is AutoApi?

AutoApi scans your assemblies at startup for classes decorated with [AutoApi] and automatically registers full GET / GET by id / POST / PUT / DELETE minimal-API endpoints — wired up to a data store of your choice.

Your model  +  [AutoApi]  →  5 REST endpoints, zero controllers

Works with any data source through the IAutoApiStore<T> interface — comes with a built-in in-memory store for rapid prototyping and an EF Core store for production.

Installation

dotnet add package AutoApi

Requires .NET 8 or later.

Quick Start

1. Decorate your model:

using AutoApi.Core.Attributes;

[AutoApi]
public class Product
{
    public int    Id    { get; set; }
    public string Name  { get; set; } = "";
    public decimal Price { get; set; }
}

2. Register in Program.cs:

using AutoApi.Core.Extensions;

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddAutoApi();          // scan + register stores

var app = builder.Build();

app.MapAutoApiEndpoints();              // wire up all routes

app.Run();

That's it. Your API is live:

GET     /api/product        → list all products
GET     /api/product/{id}   → get by id
POST    /api/product        → create
PUT     /api/product/{id}   → update
DELETE  /api/product/{id}   → delete

Generated Endpoints

Configuration

All configuration is done via the AddAutoApi options callback.

Route Prefix

builder.Services.AddAutoApi(o =>
{
    o.RoutePrefix = "v1/api";   // → /v1/api/product
    // o.RoutePrefix = "";      // → /product  (no prefix)
});

Default: "api" → /api/{classname}

Custom Route per Model

[AutoApi(Route = "catalog/products")]
public class Product { ... }
// → /catalog/products

Restrict HTTP Methods

[AutoApi(AllowedMethods = new[] { "GET" })]
public class ReadOnlyReport { ... }
// Only GET / GET-by-id are registered

[AutoApi(AllowedMethods = new[] { "GET", "POST" })]
public class Order { ... }

Swagger / OpenAPI Tags

[AutoApi(Tag = "Inventory")]
public class Product { ... }
// All product endpoints appear under the "Inventory" group in Swagger UI

Default: the class name.

Scan Multiple Assemblies

builder.Services.AddAutoApi(o =>
{
    o.Assemblies.Add(typeof(Product).Assembly);
    o.Assemblies.Add(typeof(Order).Assembly);
});

By default the entry assembly is scanned automatically.

Stores

In-Memory Store (default)

When no custom store is registered, AutoApi uses a thread-safe in-memory store automatically.

✅ Zero setup       ✅ Great for prototyping / testing
❌ Not persistent   ❌ Not suitable for production

Your model must have a public int Id { get; set; } property.

EF Core Store

For production use, swap in the included EFCoreAutoApiStore<T, TContext>:

// 1. Your DbContext
public class AppDbContext : DbContext
{
    public DbSet<Product> Products => Set<Product>();
}

// 2. Register in Program.cs
builder.Services.AddAutoApi(o =>
{
    o.UseStore<Product, EFCoreAutoApiStore<Product, AppDbContext>>();
});

builder.Services.AddDbContext<AppDbContext>(opt =>
    opt.UseSqlite("Data Source=app.db"));

✅ Persistent   ✅ Works with any EF Core provider (SQL Server, Postgres, SQLite, etc.)

Custom Store

Implement IAutoApiStore<T> for any data source (Dapper, MongoDB, Redis, external API, …):

public class ProductDapperStore : IAutoApiStore<Product>
{
    private readonly IDbConnection _db;
    public ProductDapperStore(IDbConnection db) => _db = db;

    public Task<IEnumerable<Product>> GetAllAsync() =>
        _db.QueryAsync<Product>("SELECT * FROM Products");

    public Task<Product?> GetByIdAsync(int id) =>
        _db.QueryFirstOrDefaultAsync<Product>(
            "SELECT * FROM Products WHERE Id = @id", new { id });

    public async Task<Product> CreateAsync(Product item) { /* ... */ }
    public async Task<Product> UpdateAsync(int id, Product item) { /* ... */ }
    public async Task DeleteAsync(int id) { /* ... */ }
}

// Register
builder.Services.AddAutoApi(o =>
    o.UseStore<Product, ProductDapperStore>());

Full Example

// Models/Product.cs
using AutoApi.Core.Attributes;

[AutoApi(Route = "products", Tag = "Catalog", AllowedMethods = new[] { "GET", "POST", "PUT", "DELETE" })]
public class Product
{
    public int     Id       { get; set; }
    public string  Name     { get; set; } = "";
    public decimal Price    { get; set; }
    public int     Stock    { get; set; }
}

[AutoApi(AllowedMethods = new[] { "GET" })]   // read-only
public class Category
{
    public int    Id   { get; set; }
    public string Name { get; set; } = "";
}

// Program.cs
using AutoApi.Core.Extensions;
using AutoApi.EFCore;

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

builder.Services.AddDbContext<AppDbContext>(opt =>
    opt.UseSqlite("Data Source=shop.db"));

builder.Services.AddAutoApi(o =>
{
    o.RoutePrefix = "api/v1";
    o.UseStore<Product,  EFCoreAutoApiStore<Product,  AppDbContext>>();
    o.UseStore<Category, EFCoreAutoApiStore<Category, AppDbContext>>();
});

var app = builder.Build();

app.UseSwagger();
app.UseSwaggerUI();

app.MapAutoApiEndpoints();

app.Run();

Resulting routes:

GET    /api/v1/products         GET    /api/v1/category
GET    /api/v1/products/{id}    GET    /api/v1/category/{id}
POST   /api/v1/products
PUT    /api/v1/products/{id}
DELETE /api/v1/products/{id}

FAQ

Does my model need an Id property?
Yes — both the built-in InMemoryStore and EFCoreAutoApiStore key records by public int Id. Custom stores have no such restriction.

Can I use it alongside regular controllers?
Absolutely. AutoApi only registers minimal-API routes; it doesn't interfere with controllers or other middleware.

Can I add auth / rate limiting to the generated endpoints?
Yes — wrap MapAutoApiEndpoints() with a route group that has auth policies applied, or extend EndpointBuilder with your own middleware pipeline.

Does it support Swagger/OpenAPI?
Yes. Every endpoint is tagged (via WithTags) and named (WithName). Add AddEndpointsApiExplorer() + AddSwaggerGen() and they appear automatically.

What happens if two models have the same class name?
They'll resolve to the same route, which will cause a conflict at startup. Use the Route property on [AutoApi] to give each a unique path.

Contributing

Pull requests are welcome! Please read the PR template before opening one.

1. Fork the repo
2. Create a branch: git checkout -b feature/my-feature
3. Make your changes with tests
4. Push and open a PR against main

The CI pipeline enforces zero warnings and full test coverage on every PR.

License

MIT © Sourav Das