# Go OTel Debugger

This is a debug OpenTelemetry receiver that accepts traces, metrics, and logs via OTLP HTTP protocol and broadcasts them over WebSocket connections for real-time visualization.

## Features

- Receives OTLP traces, metrics, and logs over HTTP
- Broadcasts received telemetry data over WebSocket connections
- Supports both JSON and Protocol Buffer formats
- Real-time debugging and visualization

## Getting Started

### Prerequisites

- Go 1.21+
- Docker (optional)

### Running Locally

1. Clone the repository:
   ```sh
   git clone https://git.tornberg.me/go-otel.git
   cd go-otel
   ```

2. Run the server:
   ```sh
   go run ./cmd/server
   ```

The server will be running on port 8080.

### Running with Docker

1. Build the Docker image:
   ```sh
   docker build -t go-otel .
   ```

2. Run the Docker container:
   ```sh
   docker run -p 8080:8080 go-otel
   ```

## API

### OTLP HTTP Endpoints

- **POST /v1/traces**: Receive OTLP traces
- **POST /v1/metrics**: Receive OTLP metrics  
- **POST /v1/logs**: Receive OTLP logs

Supported Content-Types:
- `application/json`
- `application/x-protobuf`

### OTLP gRPC Endpoints

- **gRPC service**: `otlptracegrpc.TraceService.Export`
- **gRPC service**: `otlptracegrpc.MetricsService.Export`
- **gRPC service**: `otlptracegrpc.LogsService.Export`

gRPC server runs on port 4317 (standard OTLP gRPC port).

### WebSocket

- **GET /ws**: Connect to receive real-time telemetry data

## Usage

Send OTLP data to the appropriate endpoints. The data will be broadcast to all connected WebSocket clients for visualization.

Open `http://localhost:8080` in your browser to access the web-based visualizer.

### HTTP Examples

Example with curl (JSON):
```sh
curl -X POST http://localhost:8080/v1/traces \
  -H "Content-Type: application/json" \
  -d @trace-data.json
```

### gRPC Examples

Use OTLP gRPC clients or libraries to send data to `localhost:4317`.

### WebSocket

Connect to WebSocket to receive the data:
```javascript
const ws = new WebSocket('ws://localhost:8080/ws');
ws.onmessage = (event) => {
  console.log('Received:', JSON.parse(event.data));
};
```

## Web Interface

The web interface provides real-time visualization of:
- Traces
- Metrics  
- Logs

Features:
- Live data streaming via WebSocket
- Separate sections for each telemetry type
- Message counters
- Clear buttons for each section
- Connection status indicator

## Testing

A test client is included to verify that the receiver works correctly.

### Run the Test

1. Start the receiver:
   ```sh
   go run ./cmd/server
   ```

2. In another terminal, run the test client:
   ```sh
   cd test-client && go run .
   ```

Or use the provided test script:
```sh
./test.sh
```

The test client will send sample traces via both HTTP and gRPC protocols.

### Manual Testing

#### HTTP Testing
```sh
curl -X POST http://localhost:8080/v1/traces \
  -H "Content-Type: application/json" \
  -d '{"resourceSpans":[{"resource":{"attributes":[{"key":"service.name","value":{"stringValue":"test-service"}}]},"scopeSpans":[{"scope":{"name":"test-scope"},"spans":[{"traceId":"0102030405060708090a0b0c0d0e0f10","spanId":"0102030405060708","name":"test-span","startTimeUnixNano":"1640995200000000000","endTimeUnixNano":"1640995260000000000","attributes":[{"key":"test.key","value":{"stringValue":"test-value"}}]}]}]}]}'
```

#### Web Interface
Open `http://localhost:8080` in your browser to see the real-time visualization.