151 lines
5.1 KiB
Markdown
151 lines
5.1 KiB
Markdown
# Go OTel Debugger
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A debug receiver for OpenTelemetry telemetry data (traces, metrics, and logs) that provides real-time visualization and historical data access. It accepts OTLP data via HTTP and gRPC protocols, stores a configurable history of received telemetry, and broadcasts updates to connected WebSocket clients for live debugging.
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## Features
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- **OTLP Support**: Receives traces, metrics, and logs via both HTTP (JSON/Protobuf) and gRPC (Protobuf) protocols on standard OTLP ports.
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- **Real-time Broadcasting**: Uses WebSocket connections to broadcast incoming telemetry data to all connected clients instantly.
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- **Historical Data**: Maintains a configurable ring buffer of recent telemetry data, accessible via REST API endpoints.
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- **Web Interface**: Includes a built-in HTML interface for visualizing telemetry data in real-time with counters and clear buttons.
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- **Docker Support**: Containerized for easy deployment.
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- **Kubernetes Ready**: Includes deployment manifests for Kubernetes clusters.
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## Architecture
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The application consists of several key components:
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1. **HTTP/gRPC Servers**: Handle incoming OTLP requests on ports 8080 (HTTP) and 4317 (gRPC).
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2. **Collector**: Processes and stores telemetry data in a ring buffer for history. Implements OpenTelemetry consumer interfaces.
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3. **WebSocket Server**: Manages client connections and broadcasts new telemetry data as JSON messages.
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4. **Web Interface**: Static HTML page served on the root path that connects to the WebSocket for real-time updates.
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5. **History API**: REST endpoints to retrieve stored telemetry data by type or all combined.
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Data flow:
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```
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OTLP Client → HTTP/gRPC Server → Collector → WebSocket Broadcast → Connected Clients
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↓
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History Storage → REST API → Clients
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```
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## Getting Started
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### Prerequisites
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- Go 1.25+ (for local development)
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- Docker (optional, for containerized deployment)
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### Running Locally
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1. Clone the repository:
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```sh
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git clone https://git.tornberg.me/go-otel.git
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cd go-otel
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```
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2. Run the server:
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```sh
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go run ./cmd/server
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```
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The server will start on ports 8080 (HTTP/WebSocket) and 4317 (gRPC).
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### Running with Docker
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1. Build the Docker image:
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```sh
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docker build -t go-otel .
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```
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2. Run the container:
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```sh
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docker run -p 8080:8080 -p 4317:4317 go-otel
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```
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### Kubernetes Deployment
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Apply the included Kubernetes manifests:
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```sh
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kubectl apply -f k8s/
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```
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This deploys the application with a Service and Ingress for external access.
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## API Endpoints
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### OTLP HTTP Endpoints (Port 8080)
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- `POST /v1/traces` - Receive OTLP traces
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- `POST /v1/metrics` - Receive OTLP metrics
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- `POST /v1/logs` - Receive OTLP logs
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Supported Content-Types: `application/json`, `application/x-protobuf`
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### OTLP gRPC Endpoints (Port 4317)
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gRPC services for traces, metrics, and logs using standard OTLP protobuf definitions.
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### WebSocket Endpoint (Port 8080)
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- `GET /ws` - WebSocket connection for real-time telemetry streaming
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### History API Endpoints (Port 8080)
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- `GET /api/history` - Retrieve all historical telemetry data
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- `GET /api/history/traces` - Retrieve only trace history
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- `GET /api/history/metrics` - Retrieve only metrics history
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- `GET /api/history/logs` - Retrieve only logs history
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### Web Interface
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- `GET /` - Serves the HTML visualization interface
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## Usage
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### Sending Telemetry Data
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Send OTLP data to the appropriate endpoints. The data will be stored in history and broadcast to all connected WebSocket clients.
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#### HTTP Example (JSON)
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```sh
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curl -X POST http://localhost:8080/v1/traces \
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-H "Content-Type: application/json" \
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-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"}}]}]}]}]}'
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```
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#### gRPC Example
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Use any OTLP gRPC client library to send data to `localhost:4317`.
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### Real-time Visualization
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1. Open `http://localhost:8080` in your browser
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2. The interface will automatically connect via WebSocket
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3. Send telemetry data to see it appear in real-time
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4. Use the "Clear" buttons to reset individual data sections
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5. View message counters for each telemetry type
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### Accessing Historical Data
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Use the history API endpoints to retrieve previously received data:
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```sh
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curl http://localhost:8080/api/history/traces
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```
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This returns JSON arrays of historical entries with timestamps.
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## Configuration
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Currently, the history buffer size is hardcoded to 100 entries. This can be made configurable in future versions.
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## Development
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To modify the application:
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1. Edit source files in `cmd/server/` and `internal/`
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2. Run locally with `go run ./cmd/server`
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3. For UI changes, edit `index.html` directly
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The application uses standard Go modules and OpenTelemetry collector libraries for data processing. |