Add capability contract interfaces for HTTP and data persistence

packages/runtime/README.md

@@ -6,9 +6,12 @@ ObjectStack Core Runtime & Query Engine
 
 The runtime package provides the `ObjectKernel` (MiniKernel) - a highly modular, plugin-based microkernel that orchestrates ObjectStack applications. It manages the application lifecycle through a standardized plugin system with dependency injection and event hooks.
 
+The package also defines **capability contract interfaces** (`IHttpServer`, `IDataEngine`) that enable plugins to interact with common services without depending on concrete implementations, following the **Dependency Inversion Principle**.
+
 ### Architecture Highlights
 
 - **MiniKernel Design**: Business logic is completely separated into plugins
+- **Capability Contracts**: Abstract interfaces for HTTP server and data persistence
 - **Dependency Injection**: Service registry for inter-plugin communication
 - **Event/Hook System**: Publish-subscribe mechanism for loose coupling
 - **Lifecycle Management**: Standardized init/start/destroy phases
@@ -119,6 +122,91 @@ new AppManifestPlugin(appConfig)
 
 ## API Reference
 
+### Capability Contract Interfaces
+
+#### IHttpServer
+
+Abstract interface for HTTP server capabilities. Allows plugins to work with any HTTP framework (Express, Fastify, Hono, etc.) without tight coupling.
+
+```typescript
+import { IHttpServer, IHttpRequest, IHttpResponse } from '@objectstack/runtime';
+
+// In your HTTP server plugin
+class MyHttpServerPlugin implements Plugin {
+  name = 'http-server';
+
+  async init(ctx: PluginContext) {
+    const server: IHttpServer = createMyServer(); // Express, Hono, etc.
+    ctx.registerService('http-server', server);
+  }
+}
+
+// In your API plugin
+class MyApiPlugin implements Plugin {
+  name = 'api';
+  dependencies = ['http-server'];
+
+  async start(ctx: PluginContext) {
+    const server = ctx.getService<IHttpServer>('http-server');
+
+    // Register routes - works with any HTTP framework
+    server.get('/api/users', async (req, res) => {
+      res.json({ users: [] });
+    });
+  }
+}
+```
+
+**Interface Methods:**
+- `get(path, handler)` - Register GET route
+- `post(path, handler)` - Register POST route  
+- `put(path, handler)` - Register PUT route
+- `delete(path, handler)` - Register DELETE route
+- `patch(path, handler)` - Register PATCH route
+- `use(path, handler?)` - Register middleware
+- `listen(port)` - Start server
+- `close()` - Stop server (optional)
+
+#### IDataEngine
+
+Abstract interface for data persistence. Allows plugins to work with any data layer (ObjectQL, Prisma, TypeORM, etc.) without tight coupling.
+
+```typescript
+import { IDataEngine } from '@objectstack/runtime';
+
+// In your data plugin
+class MyDataPlugin implements Plugin {
+  name = 'data';
+
+  async init(ctx: PluginContext) {
+    const engine: IDataEngine = createMyDataEngine(); // ObjectQL, Prisma, etc.
+    ctx.registerService('data-engine', engine);
+  }
+}
+
+// In your business logic plugin
+class MyBusinessPlugin implements Plugin {
+  name = 'business';
+  dependencies = ['data'];
+
+  async start(ctx: PluginContext) {
+    const engine = ctx.getService<IDataEngine>('data-engine');
+
+    // CRUD operations - works with any data layer
+    const user = await engine.insert('user', { name: 'John' });
+    const users = await engine.find('user', { filter: { active: true } });
+    await engine.update('user', user.id, { name: 'Jane' });
+    await engine.delete('user', user.id);
+  }
+}
+```
+
+**Interface Methods:**
+- `insert(objectName, data)` - Create a record
+- `find(objectName, query?)` - Query records
+- `update(objectName, id, data)` - Update a record
+- `delete(objectName, id)` - Delete a record
+
 ### ObjectKernel
 
 #### Methods
@@ -161,17 +249,18 @@ interface PluginContext {
 See the `examples/` directory for complete examples:
 - `examples/host/` - Full server setup with Hono
 - `examples/msw-react-crud/` - Browser-based setup with MSW
-- `examples/custom-objectql-example.ts` - Custom ObjectQL instance
-- `test-mini-kernel.ts` - Comprehensive test suite
+- `test-mini-kernel.ts` - Comprehensive kernel test suite
+- `packages/runtime/src/test-interfaces.ts` - Capability contract interface examples
 
 ## Benefits of MiniKernel
 
 1. **True Modularity**: Each plugin is independent and reusable
-2. **Testability**: Mock services easily in tests
-3. **Flexibility**: Load plugins conditionally
-4. **Extensibility**: Add new plugins without modifying kernel
-5. **Clear Dependencies**: Explicit dependency declarations
-6. **Better Architecture**: Separation of concerns
+2. **Capability Contracts**: Plugins depend on interfaces, not implementations
+3. **Testability**: Mock services easily in tests
+4. **Flexibility**: Load plugins conditionally, swap implementations
+5. **Extensibility**: Add new plugins without modifying kernel
+6. **Clear Dependencies**: Explicit dependency declarations
+7. **Better Architecture**: Separation of concerns with Dependency Inversion
 
 ## Best Practices
 

packages/runtime/src/index.ts

@@ -15,3 +15,7 @@ export { ObjectStackRuntimeProtocol } from './protocol.js';
 // Export Types
 export * from './types.js';
 
+// Export Interfaces (Capability Contracts)
+export * from './interfaces/http-server.js';
+export * from './interfaces/data-engine.js';
+

packages/runtime/src/interfaces/data-engine.ts

@@ -0,0 +1,122 @@
+/**
+ * IDataEngine - Standard Data Engine Interface
+ * 
+ * Abstract interface for data persistence capabilities.
+ * This allows plugins to interact with data engines without knowing
+ * the underlying implementation (SQL, MongoDB, Memory, etc.).
+ * 
+ * Follows Dependency Inversion Principle - plugins depend on this interface,
+ * not on concrete database implementations.
+ */
+
+/**
+ * Query filter conditions
+ */
+export interface QueryFilter {
+    [field: string]: any;
+}
+
+/**
+ * Query options for find operations
+ */
+export interface QueryOptions {
+    /** Filter conditions */
+    filter?: QueryFilter;
+    /** Fields to select */
+    select?: string[];
+    /** Sort order */
+    sort?: Record<string, 1 | -1 | 'asc' | 'desc'>;
+    /** Limit number of results (alternative name for top, used by some drivers) */
+    limit?: number;
+    /** Skip number of results (for pagination) */
+    skip?: number;
+    /** Maximum number of results (OData-style, takes precedence over limit if both specified) */
+    top?: number;
+}
+
+/**
+ * IDataEngine - Data persistence capability interface
+ * 
+ * Defines the contract for data engine implementations.
+ * Concrete implementations (ObjectQL, Prisma, TypeORM) should implement this interface.
+ */
+export interface IDataEngine {
+    /**
+     * Insert a new record
+     * 
+     * @param objectName - Name of the object/table (e.g., 'user', 'order')
+     * @param data - Data to insert
+     * @returns Promise resolving to the created record (including generated ID)
+     * 
+     * @example
+     * ```ts
+     * const user = await engine.insert('user', {
+     *   name: 'John Doe',
+     *   email: 'john@example.com'
+     * });
+     * console.log(user.id); // Auto-generated ID
+     * ```
+     */
+    insert(objectName: string, data: any): Promise<any>;
+
+    /**
+     * Find records matching a query
+     * 
+     * @param objectName - Name of the object/table
+     * @param query - Query conditions (optional)
+     * @returns Promise resolving to an array of matching records
+     * 
+     * @example
+     * ```ts
+     * // Find all users
+     * const allUsers = await engine.find('user');
+     * 
+     * // Find with filter
+     * const activeUsers = await engine.find('user', {
+     *   filter: { status: 'active' }
+     * });
+     * 
+     * // Find with limit and sort
+     * const recentUsers = await engine.find('user', {
+     *   sort: { createdAt: -1 },
+     *   limit: 10
+     * });
+     * ```
+     */
+    find(objectName: string, query?: QueryOptions): Promise<any[]>;
+
+    /**
+     * Update a record by ID
+     * 
+     * @param objectName - Name of the object/table
+     * @param id - Record ID
+     * @param data - Updated data (partial update)
+     * @returns Promise resolving to the updated record
+     * 
+     * @example
+     * ```ts
+     * const updatedUser = await engine.update('user', '123', {
+     *   name: 'Jane Doe',
+     *   email: 'jane@example.com'
+     * });
+     * ```
+     */
+    update(objectName: string, id: any, data: any): Promise<any>;
+
+    /**
+     * Delete a record by ID
+     * 
+     * @param objectName - Name of the object/table
+     * @param id - Record ID
+     * @returns Promise resolving to true if deleted, false otherwise
+     * 
+     * @example
+     * ```ts
+     * const deleted = await engine.delete('user', '123');
+     * if (deleted) {
+     *   console.log('User deleted successfully');
+     * }
+     * ```
+     */
+    delete(objectName: string, id: any): Promise<boolean>;
+}