feat: express decorators for rest apis and websocket (#6818)

* feat: express decorators for rest apis and websocket

* fix: added package dependency

* fix: refactor decorators

packages/decorators/.eslintignore

@@ -0,0 +1,4 @@
+node_modules
+build/*
+dist/*
+out/*

packages/decorators/.eslintrc.js

@@ -0,0 +1,10 @@
+/** @type {import("eslint").Linter.Config} */
+module.exports = {
+  root: true,
+  extends: ["@plane/eslint-config/library.js"],
+  parser: "@typescript-eslint/parser",
+  parserOptions: {
+    project: true,
+  },
+};
+

packages/decorators/README.md

@@ -0,0 +1,99 @@
+# @plane/decorators
+
+A lightweight TypeScript decorator library for building Express.js controllers with a clean, declarative syntax.
+
+## Features
+
+- TypeScript-first design
+- Decorators for HTTP methods (GET, POST, PUT, PATCH, DELETE)
+- WebSocket support
+- Middleware support
+- No build step required - works directly with TypeScript files
+
+## Installation
+
+This package is part of the Plane workspace and can be used by adding it to your project's dependencies:
+
+```json
+{
+  "dependencies": {
+    "@plane/decorators": "*"
+  }
+}
+```
+
+## Usage
+
+### Basic REST Controller
+
+```typescript
+import { Controller, Get, Post, BaseController } from "@plane/decorators";
+import { Router, Request, Response } from "express";
+
+@Controller("/api/users")
+class UserController extends BaseController {
+  @Get("/")
+  async getUsers(req: Request, res: Response) {
+    return res.json({ users: [] });
+  }
+
+  @Post("/")
+  async createUser(req: Request, res: Response) {
+    return res.json({ success: true });
+  }
+}
+
+// Register routes
+const router = Router();
+const userController = new UserController();
+userController.registerRoutes(router);
+```
+
+### WebSocket Controller
+
+```typescript
+import {
+  Controller,
+  WebSocket,
+  BaseWebSocketController,
+} from "@plane/decorators";
+import { Request } from "express";
+import { WebSocket as WS } from "ws";
+
+@Controller("/ws/chat")
+class ChatController extends BaseWebSocketController {
+  @WebSocket("/")
+  handleConnection(ws: WS, req: Request) {
+    ws.on("message", (message) => {
+      ws.send(`Received: ${message}`);
+    });
+  }
+}
+
+// Register WebSocket routes
+const router = require("express-ws")(app).router;
+const chatController = new ChatController();
+chatController.registerWebSocketRoutes(router);
+```
+
+## API Reference
+
+### Decorators
+
+- `@Controller(baseRoute: string)` - Class decorator for defining a base route
+- `@Get(route: string)` - Method decorator for HTTP GET endpoints
+- `@Post(route: string)` - Method decorator for HTTP POST endpoints
+- `@Put(route: string)` - Method decorator for HTTP PUT endpoints
+- `@Patch(route: string)` - Method decorator for HTTP PATCH endpoints
+- `@Delete(route: string)` - Method decorator for HTTP DELETE endpoints
+- `@WebSocket(route: string)` - Method decorator for WebSocket endpoints
+- `@Middleware(middleware: RequestHandler)` - Method decorator for applying middleware
+
+### Classes
+
+- `BaseController` - Base class for REST controllers
+- `BaseWebSocketController` - Base class for WebSocket controllers
+
+## License
+
+This project is licensed under the [GNU Affero General Public License v3.0](https://github.com/makeplane/plane/blob/master/LICENSE.txt).

packages/decorators/package.json

@@ -0,0 +1,42 @@
+{
+  "name": "@plane/decorators",
+  "version": "0.1.0",
+  "description": "Controller and route decorators for Express.js applications",
+  "license": "AGPL-3.0",
+  "private": true,
+  "main": "./dist/index.js",
+  "module": "./dist/index.mjs",
+  "types": "./dist/index.d.ts",
+  "files": [
+    "dist/**"
+  ],
+  "scripts": {
+    "build": "tsup src/index.ts --format esm,cjs --dts --external express,ws",
+    "dev": "tsup src/index.ts --format esm,cjs --watch --dts --external express,ws",
+    "lint": "eslint src --ext .ts,.tsx",
+    "lint:errors": "eslint src --ext .ts,.tsx --quiet"
+  },
+  "dependencies": {
+    "reflect-metadata": "^0.2.2",
+    "express": "^4.21.2"
+  },
+  "devDependencies": {
+    "@plane/eslint-config": "*",
+    "@types/express": "^4.17.21",
+    "@types/reflect-metadata": "^0.1.0",
+    "@plane/typescript-config": "*",
+    "@types/node": "^20.14.9",
+    "@types/ws": "^8.5.10",
+    "tsup": "8.3.0",
+    "typescript": "^5.3.3"
+  },
+  "peerDependencies": {
+    "express": ">=4.21.2",
+    "ws": ">=8.0.0"
+  },
+  "peerDependenciesMeta": {
+    "ws": {
+      "optional": true
+    }
+  }
+}

packages/decorators/src/controller.ts

@@ -0,0 +1,61 @@
+import { RequestHandler, Router } from "express";
+import "reflect-metadata";
+
+type HttpMethod =
+  | "get"
+  | "post"
+  | "put"
+  | "delete"
+  | "patch"
+  | "options"
+  | "head"
+  | "ws";
+
+interface ControllerInstance {
+  [key: string]: unknown;
+}
+
+interface ControllerConstructor {
+  new (...args: any[]): ControllerInstance;
+  prototype: ControllerInstance;
+}
+
+export function registerControllers(
+  router: Router,
+  Controller: ControllerConstructor,
+): void {
+  const instance = new Controller();
+  const baseRoute = Reflect.getMetadata("baseRoute", Controller) as string;
+
+  Object.getOwnPropertyNames(Controller.prototype).forEach((methodName) => {
+    if (methodName === "constructor") return; // Skip the constructor
+
+    const method = Reflect.getMetadata(
+      "method",
+      instance,
+      methodName,
+    ) as HttpMethod;
+    const route = Reflect.getMetadata("route", instance, methodName) as string;
+    const middlewares =
+      (Reflect.getMetadata(
+        "middlewares",
+        instance,
+        methodName,
+      ) as RequestHandler[]) || [];
+
+    if (method && route) {
+      const handler = instance[methodName] as unknown;
+
+      if (typeof handler === "function") {
+        if (method !== "ws") {
+          (
+            router[method] as (
+              path: string,
+              ...handlers: RequestHandler[]
+            ) => void
+          )(`${baseRoute}${route}`, ...middlewares, handler.bind(instance));
+        }
+      }
+    }
+  });
+}

packages/decorators/src/index.ts

@@ -0,0 +1,15 @@
+// Export individual decorators
+export { Controller, Middleware } from "./rest";
+export { Get, Post, Put, Patch, Delete } from "./rest";
+export { WebSocket } from "./websocket";
+export { registerControllers } from "./controller";
+export { registerWebSocketControllers } from "./websocket-controller";
+
+// Also provide namespaced exports for better organization
+import * as RestDecorators from "./rest";
+import * as WebSocketDecorators from "./websocket";
+
+// Named namespace exports
+export const Rest = RestDecorators;
+export const WebSocketNS = WebSocketDecorators;
+

packages/decorators/src/rest.ts

@@ -0,0 +1,61 @@
+import "reflect-metadata";
+import { RequestHandler } from "express";
+
+// Define valid HTTP methods
+type RestMethod = "get" | "post" | "put" | "patch" | "delete";
+
+/**
+ * Controller decorator
+ * @param baseRoute
+ * @returns
+ */
+export function Controller(baseRoute: string = ""): ClassDecorator {
+  return function (target: Function) {
+    Reflect.defineMetadata("baseRoute", baseRoute, target);
+  };
+}
+
+/**
+ * Factory function to create HTTP method decorators
+ * @param method HTTP method to handle
+ * @returns Method decorator
+ */
+function createHttpMethodDecorator(
+  method: RestMethod
+): (route: string) => MethodDecorator {
+  return function (route: string): MethodDecorator {
+    return function (
+      target: object,
+      propertyKey: string | symbol,
+      descriptor: PropertyDescriptor
+    ) {
+      Reflect.defineMetadata("method", method, target, propertyKey);
+      Reflect.defineMetadata("route", route, target, propertyKey);
+    };
+  };
+}
+
+// Export HTTP method decorators using the factory
+export const Get = createHttpMethodDecorator("get");
+export const Post = createHttpMethodDecorator("post");
+export const Put = createHttpMethodDecorator("put");
+export const Patch = createHttpMethodDecorator("patch");
+export const Delete = createHttpMethodDecorator("delete");
+
+/**
+ * Middleware decorator
+ * @param middleware
+ * @returns
+ */
+export function Middleware(middleware: RequestHandler): MethodDecorator {
+  return function (
+    target: object,
+    propertyKey: string | symbol,
+    descriptor: PropertyDescriptor,
+  ) {
+    const middlewares =
+      Reflect.getMetadata("middlewares", target, propertyKey) || [];
+    middlewares.push(middleware);
+    Reflect.defineMetadata("middlewares", middlewares, target, propertyKey);
+  };
+}

packages/decorators/src/websocket-controller.ts

@@ -0,0 +1,85 @@
+import { Router, Request } from "express";
+import type { WebSocket } from "ws";
+import "reflect-metadata";
+
+interface ControllerInstance {
+  [key: string]: unknown;
+}
+
+interface ControllerConstructor {
+  new (...args: any[]): ControllerInstance;
+  prototype: ControllerInstance;
+}
+
+export function registerWebSocketControllers(
+  router: Router,
+  Controller: ControllerConstructor,
+  existingInstance?: ControllerInstance,
+): void {
+  const instance = existingInstance || new Controller();
+  const baseRoute = Reflect.getMetadata("baseRoute", Controller) as string;
+
+  Object.getOwnPropertyNames(Controller.prototype).forEach((methodName) => {
+    if (methodName === "constructor") return; // Skip the constructor
+
+    const method = Reflect.getMetadata(
+      "method",
+      instance,
+      methodName,
+    ) as string;
+    const route = Reflect.getMetadata("route", instance, methodName) as string;
+
+    if (method === "ws" && route) {
+      const handler = instance[methodName] as unknown;
+
+      if (
+        typeof handler === "function" &&
+        typeof (router as any).ws === "function"
+      ) {
+        (router as any).ws(
+          `${baseRoute}${route}`,
+          (ws: WebSocket, req: Request) => {
+            try {
+              handler.call(instance, ws, req);
+            } catch (error) {
+              console.error(
+                `WebSocket error in ${Controller.name}.${methodName}`,
+                error,
+              );
+              ws.close(
+                1011,
+                error instanceof Error
+                  ? error.message
+                  : "Internal server error",
+              );
+            }
+          },
+        );
+      }
+    }
+  });
+}
+
+/**
+ * Base controller class for WebSocket endpoints
+ */
+export abstract class BaseWebSocketController {
+  protected router: Router;
+
+  constructor() {
+    this.router = Router();
+  }
+
+  /**
+   * Get the base route for this controller
+   */
+  protected getBaseRoute(): string {
+    return Reflect.getMetadata("baseRoute", this.constructor) || "";
+  }
+
+  /**
+   * Abstract method to handle WebSocket connections
+   * Implement this in your derived class
+   */
+  abstract handleConnection(ws: WebSocket, req: Request): void;
+}

packages/decorators/src/websocket.ts

@@ -0,0 +1,17 @@
+import "reflect-metadata";
+
+/**
+ * WebSocket method decorator
+ * @param route
+ * @returns
+ */
+export function WebSocket(route: string): MethodDecorator {
+  return function (
+    target: object,
+    propertyKey: string | symbol,
+    descriptor: PropertyDescriptor,
+  ) {
+    Reflect.defineMetadata("method", "ws", target, propertyKey);
+    Reflect.defineMetadata("route", route, target, propertyKey);
+  };
+}

packages/decorators/tsconfig.json

@@ -0,0 +1,21 @@
+{
+  "extends": "@plane/typescript-config/node-library.json",
+  "compilerOptions": {
+    "experimentalDecorators": true,
+    "emitDecoratorMetadata": true,
+    "lib": ["ES2020"],
+    "rootDir": ".",
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["./src/*"]
+    }
+  },
+  "include": [
+    "./src"
+  ],
+  "exclude": [
+    "dist",
+    "build",
+    "node_modules"
+  ]
+}

packages/decorators/tsup.config.ts

@@ -0,0 +1,12 @@
+import { defineConfig } from 'tsup';
+
+export default defineConfig({
+  entry: ['src/index.ts'],
+  format: ['esm', 'cjs'],
+  dts: true,
+  splitting: false,
+  sourcemap: true,
+  clean: true,
+  external: ['express', 'ws'],
+  treeshake: true,
+}); 

packages/typescript-config/node-library.json

@@ -0,0 +1,26 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  "display": "Node.js Library",
+  "extends": "./base.json",
+  "compilerOptions": {
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "target": "ES2020",
+    "lib": ["ES2020"],
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["./src/*"]
+    },
+    "sourceMap": true,
+    "inlineSources": true,
+    "experimentalDecorators": true,
+    "emitDecoratorMetadata": true,
+    "resolveJsonModule": true,
+    "allowSyntheticDefaultImports": true,
+    "forceConsistentCasingInFileNames": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist", "build"]
+} 

packages/typescript-config/package.json

@@ -6,6 +6,7 @@
   "files": [
     "base.json",
     "nextjs.json",
-    "react-library.json"
+    "react-library.json",
+    "node-library.json"
   ]
 }