feat: implement self-contained plugin system architecture in middleware

backend/src/core/PluginLoader.ts

@@ -0,0 +1,8 @@
+import { Plugin } from "./types";
+
+export class PluginLoader {
+  static async load(path: string): Promise<Plugin> {
+    const mod = await import(path);
+    return mod.default;
+  }
+}

backend/src/core/PluginManager.ts

@@ -0,0 +1,37 @@
+import { Plugin, PluginContext } from "./types";
+import { PluginRegistry } from "./PluginRegistry";
+
+export class PluginManager {
+  private registry = new PluginRegistry();
+  private context: PluginContext;
+
+  constructor(context: PluginContext = {}) {
+    this.context = context;
+  }
+
+  register(plugin: Plugin) {
+    this.registry.register(plugin);
+  }
+
+  async initAll() {
+    for (const plugin of this.registry.getAll()) {
+      await plugin.init?.(this.context);
+    }
+  }
+
+  async startAll() {
+    for (const plugin of this.registry.getAll()) {
+      await plugin.start?.();
+    }
+  }
+
+  async stopAll() {
+    for (const plugin of this.registry.getAll()) {
+      await plugin.stop?.();
+    }
+  }
+
+  getPlugin(name: string) {
+    return this.registry.get(name);
+  }
+}

backend/src/core/lifecycle.ts

@@ -0,0 +1,5 @@
+export enum PluginLifecycle {
+    INIT = "init",
+    START = "start",
+    STOP = "stop",
+  }

backend/src/core/pluginRegistry.ts

@@ -0,0 +1,20 @@
+import { Plugin } from "./types";
+
+export class PluginRegistry {
+  private plugins: Map<string, Plugin> = new Map();
+
+  register(plugin: Plugin) {
+    if (this.plugins.has(plugin.name)) {
+      throw new Error(`Plugin ${plugin.name} already registered`);
+    }
+    this.plugins.set(plugin.name, plugin);
+  }
+
+  get(name: string): Plugin | undefined {
+    return this.plugins.get(name);
+  }
+
+  getAll(): Plugin[] {
+    return Array.from(this.plugins.values());
+  }
+}

backend/src/core/types.ts

@@ -0,0 +1,16 @@
+export type PluginContext = {
+  config?: Record<string, any>;
+  logger?: {
+    log: (...args: any[]) => void;
+    error: (...args: any[]) => void;
+  };
+};
+
+export interface Plugin {
+  name: string;
+  version: string;
+
+  init?(context: PluginContext): Promise<void> | void;
+  start?(): Promise<void> | void;
+  stop?(): Promise<void> | void;
+}