Add a client/service demo for typescript (#1195)

This PR adds a comprehensive TypeScript demo for rclnodejs, demonstrating how to create ROS2 service servers and clients using TypeScript. The demo includes a complete project structure with proper TypeScript configuration, build scripts, and detailed documentation.

Key changes:
- Adds a complete TypeScript service demo with client and server implementations
- Implements AddTwoInts service with proper type handling and error management
- Updates main README to include reference to the new TypeScript demo

Fix: #1193

Author: minggangw

.npmignore

@@ -30,3 +30,4 @@ scripts/cpplint.js
 scripts/npm-pack.sh
 scripts/npmjs-readme.md
 scripts/run_test.js
+ts_demo/

README.md

@@ -34,7 +34,8 @@ rclnodejs.init().then(() => {
 - [Using TypeScript](#using-rclnodejs-with-typescript)
 - [ROS2 Interface Message Generation](#ros2-interface-message-generation-important)
 - [Examples](https://github.com/RobotWebTools/rclnodejs/tree/develop/example)
-- [Electron demo](https://github.com/RobotWebTools/rclnodejs/tree/develop/electron_demo)
+- [Electron Demo](https://github.com/RobotWebTools/rclnodejs/tree/develop/electron_demo)
+- [TypeScript Demo](https://github.com/RobotWebTools/rclnodejs/tree/develop/ts_demo)
 - [Efficient Usage Tips](./docs/EFFICIENCY.md)
 - [FAQ and Known Issues](./docs/FAQ.md)
 - [Building from Scratch](./docs/BUILDING.md)

ts_demo/services/README.md

@@ -0,0 +1,287 @@
+# rclnodejs TypeScript Services Demo
+
+This demo demonstrates how to use **rclnodejs** with TypeScript to create ROS2 service servers and clients. The demo includes a service server that provides an `AddTwoInts` service and a client that calls the service with random numbers.
+
+## Features
+
+- 🚀 **TypeScript Support**: Fully typed ROS2 service implementation using rclnodejs TypeScript interfaces
+- 🔢 **Service Server**: Provides an AddTwoInts service that adds two integers
+- 📞 **Service Client**: Calls the AddTwoInts service with random numbers at regular intervals
+- 🛡️ **Type Safety**: Leverages TypeScript's type system for compile-time safety
+- 🎯 **Error Handling**: Comprehensive error handling and graceful shutdown
+- 📊 **Request Counting**: Tracks service requests and responses
+- 🎨 **Console Output**: Colorful and informative console messages
+- ⏱️ **Service Discovery**: Client waits for service availability before making requests
+
+## Prerequisites
+
+Before running this demo, ensure you have:
+
+1. **Node.js** (>= 16.13.0)
+2. **ROS 2** installed and sourced
+3. **rclnodejs** built and available
+
+### ROS 2 Setup
+
+Make sure your ROS 2 environment is properly sourced before running the demo:
+
+```bash
+# For example, if using ROS 2 Jazzy
+source /opt/ros/jazzy/setup.bash
+
+# Or if you have a custom workspace
+source /path/to/your/ros2_ws/install/setup.bash
+```
+
+### Verify rclnodejs Installation
+
+From the root of the rclnodejs project, ensure it's built:
+
+```bash
+cd /path/to/rclnodejs
+npm install
+npm run build
+```
+
+## Installation
+
+Navigate to this demo directory and install dependencies:
+
+```bash
+cd ts_demo/services
+npm install
+```
+
+## Usage
+
+### Build and Run
+
+1. **Build the TypeScript code:**
+
+   ```bash
+   npm run build
+   ```
+
+2. **Run the service server (in one terminal):**
+
+   ```bash
+   npm run start:server
+   ```
+
+3. **Run the service client (in another terminal):**
+
+   ```bash
+   npm run start:client
+   ```
+
+4. **Or run both simultaneously:**
+   ```bash
+   npm run start:both
+   ```
+
+### Development Mode
+
+For development, you can run TypeScript files directly with ts-node:
+
+1. **Run the service server:**
+
+   ```bash
+   npm run dev:server
+   ```
+
+2. **Run the service client:**
+
+   ```bash
+   npm run dev:client
+   ```
+
+3. **Type check only:**
+   ```bash
+   npm run check-types
+   ```
+
+## How It Works
+
+### Service Server (`server.ts`)
+
+The service server:
+
+- Creates a ROS2 node named `ts_server_demo`
+- Provides an `AddTwoInts` service at `/add_two_ints`
+- Receives requests with two integers (`a` and `b`)
+- Calculates the sum and returns it in the response
+- Logs each request and response with timestamps
+
+### Service Client (`client.ts`)
+
+The service client:
+
+- Creates a ROS2 node named `ts_client_demo`
+- Waits for the `AddTwoInts` service to become available
+- Sends requests every 3 seconds with random integers
+- Displays the results and verifies the calculations
+- Handles service availability and error cases
+
+### Example Output
+
+**Service Server:**
+
+```
+Starting TypeScript Service Server Demo...
+✓ rclnodejs initialized
+✓ Created node: /mock_namespace/ts_server_demo
+✓ Created service server: add_two_ints
+🚀 Service server is running. Press Ctrl+C to stop...
+
+🔢 [1] Received request: a=42, b=17
+📤 [1] Sending response: sum=59
+    Calculation: 42 + 17 = 59
+    Timestamp: 2025-07-16T02:30:15.123Z
+```
+
+**Service Client:**
+
+```
+Starting TypeScript Service Client Demo...
+✓ rclnodejs initialized
+✓ Created node: /mock_namespace/ts_client_demo
+✓ Created service client: add_two_ints
+⏳ Waiting for service to be available...
+✓ Service is available
+🚀 Starting to send requests. Press Ctrl+C to stop...
+
+📞 [1] Sending request: a=42, b=17
+    Timestamp: 2025-07-16T02:30:15.120Z
+📨 [1] Received response: sum=59
+    Verification: 42 + 17 = 59 ✓
+    Response time: 2025-07-16T02:30:15.125Z
+```
+
+## TypeScript Configuration
+
+This demo includes:
+
+- **Local Type Definitions**: Custom TypeScript definitions for rclnodejs in `types/rclnodejs.d.ts`
+- **Service Types**: Type definitions for `example_interfaces/srv/AddTwoInts`
+- **Strict Type Checking**: Full TypeScript strict mode enabled
+- **Build Pipeline**: Automated compilation with shebang fixing for executable JavaScript
+
+## Service Interface
+
+The `AddTwoInts` service interface:
+
+```typescript
+export interface AddTwoInts {
+  Request: {
+    a: number; // First integer
+    b: number; // Second integer
+  };
+  Response: {
+    sum: number; // Sum of a and b
+  };
+}
+```
+
+## Customization
+
+You can easily customize this demo:
+
+### Change Service Name
+
+Edit the `SERVICE_NAME` constant in both files:
+
+```typescript
+const SERVICE_NAME = 'your_custom_service';
+```
+
+### Change Request Interval
+
+Modify the `REQUEST_INTERVAL` in the client:
+
+```typescript
+const REQUEST_INTERVAL = 1000; // Send requests every 1 second
+```
+
+### Use Different Service Types
+
+To use a different service type, update the type string and interface:
+
+```typescript
+// For example, using a custom service
+const service = node.createService(
+  'your_package/srv/YourService',
+  'service_name',
+  callback
+);
+```
+
+### Add Custom Logic
+
+Modify the service callback to implement your own business logic:
+
+```typescript
+(request, response) => {
+  // Your custom service logic here
+  response.result = processRequest(request);
+};
+```
+
+## Troubleshooting
+
+### Common Issues
+
+1. **Service not available:**
+
+   ```
+   Service not available after 5 seconds
+   ```
+
+   **Solution**: Make sure the service server is running before starting the client.
+
+2. **Module not found error:**
+
+   ```
+   Cannot find module 'rclnodejs'
+   ```
+
+   **Solution**: Ensure rclnodejs is properly linked and you're in the correct directory.
+
+3. **TypeScript compilation errors:**
+   ```
+   Type errors in service definitions
+   ```
+   **Solution**: Check the type definitions in `types/rclnodejs.d.ts` match your usage.
+
+### Debugging Tips
+
+1. **Check service list:**
+
+   ```bash
+   ros2 service list
+   ros2 service type /add_two_ints
+   ```
+
+2. **Call service manually:**
+
+   ```bash
+   ros2 service call /add_two_ints example_interfaces/srv/AddTwoInts "{a: 1, b: 2}"
+   ```
+
+3. **Monitor service info:**
+   ```bash
+   ros2 service info /add_two_ints
+   ```
+
+## Next Steps
+
+After running this demo, you might want to explore:
+
+1. **Custom Service Types**: Create your own service definitions
+2. **Asynchronous Services**: Implement long-running service operations
+3. **Service Parameters**: Use ROS2 parameters in your services
+4. **Service Discovery**: Implement dynamic service discovery
+5. **Lifecycle Services**: Create managed lifecycle service nodes
+
+## License
+
+This demo is licensed under the Apache License 2.0, same as the rclnodejs project.

ts_demo/services/package.json

@@ -0,0 +1,38 @@
+{
+  "name": "rclnodejs-ts-services-demo",
+  "version": "1.0.0",
+  "description": "TypeScript demo for rclnodejs services (client and server)",
+  "main": "dist/client.js",
+  "scripts": {
+    "prebuild": "npm run clean",
+    "build": "tsc",
+    "start:server": "npm run build && node dist/server.js",
+    "start:client": "npm run build && node dist/client.js",
+    "start:both": "npm run build && concurrently \"node dist/server.js\" \"node dist/client.js\"",
+    "clean": "rimraf dist",
+    "dev:server": "ts-node src/server.ts",
+    "dev:client": "ts-node src/client.ts",
+    "check-types": "tsc --noEmit"
+  },
+  "keywords": [
+    "rclnodejs",
+    "ros2",
+    "typescript",
+    "client",
+    "server",
+    "service",
+    "demo"
+  ],
+  "author": "rclnodejs contributors",
+  "license": "Apache-2.0",
+  "devDependencies": {
+    "@types/node": "^22.16.4",
+    "concurrently": "^9.2.0",
+    "rimraf": "^6.0.1",
+    "ts-node": "^10.9.2",
+    "typescript": "^5.8.3"
+  },
+  "dependencies": {
+    "rclnodejs": "file:../../"
+  }
+}