# Gogs Webhook Server

A modular Node.js server for receiving and processing Gogs webhooks. The server logs all incoming webhooks to the console, executes configured commands based on webhook events, and provides an extensible callback system for custom event handling.

## Features

- **Persistent Job Queue**: FIFO queue ensures sequential execution and crash recovery
- **Modular Architecture**: Clean separation of concerns (server, handler, queue, logger)
- **Command Execution**: Execute shell or Node.js commands on webhook events
- **JSON Configuration**: Flexible command configuration via `commands.json`
- **Multiple Commands per Event**: Run multiple commands for each webhook event type
- **Variable Substitution**: Access repo name, branch, pusher, issue details, and more in commands
- **Branch Filtering**: Execute commands only for specific branches
- **Node.js & Shell Support**: Run both shell scripts and Node.js scripts
- **Per-Command Settings**: Configure working directory and timeout per command
- **Extensible Callback System**: Register callbacks for specific events or all events
- **Console Logging**: Colored, formatted logging of all webhook events
- **Health Check Endpoint**: Built-in health monitoring
- **Graceful Shutdown**: Saves queue state and ensures proper cleanup on process termination
- **Zero Dependencies**: Pure Node.js implementation

## Requirements

- Node.js >= 18.0.0

## Installation

```bash
npm install
```

## Usage

### Quick Start

1. Copy the example files:
```bash
cp .env.example .env
cp commands.json.example commands.json
```

2. Edit `.env` to enable/disable webhook events

3. Edit `commands.json` to configure commands for webhook events (see Configuration section below)

4. Start the server:
```bash
npm start
```

The server will start on port 3000 and execute configured commands when webhooks are received.

### Development Mode (Auto-reload)

```bash
npm run dev
```

### Running as a Systemd Service

For production deployments, you can run the server as a systemd service. This provides:
- Automatic start on system boot
- Automatic restart on failure
- Centralized logging via journalctl
- Running as an unprivileged user

See [SYSTEMD.md](./SYSTEMD.md) for detailed installation and configuration instructions.

Quick example:
```bash
# Install the service
sudo cp agent-manager.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable agent-manager
sudo systemctl start agent-manager

# View logs
journalctl -u agent-manager -f -n100
```

### Configuration

The server uses two configuration files:
1. `.env` - Enable/disable webhook events and server settings
2. `commands.json` - Define commands to execute for each event type

#### Basic Server Configuration (`.env`)

```env
HOST=0.0.0.0
PORT=3000
WEBHOOK_PATH=/webhook
WEBHOOK_SECRET=your-secret-here
```

- `HOST` - The network interface to bind to (default: `0.0.0.0` for all interfaces, use `127.0.0.1` for localhost only)
- `PORT` - The port number to listen on (default: `3000`)
- `WEBHOOK_PATH` - The URL path for webhooks (default: `/webhook`)
- `WEBHOOK_SECRET` - Optional secret for webhook verification

#### Enable/Disable Events (`.env`)

```env
WEBHOOK_PUSH_ENABLED=true
WEBHOOK_PULL_REQUEST_ENABLED=false
WEBHOOK_CREATE_ENABLED=false
WEBHOOK_DELETE_ENABLED=false
WEBHOOK_RELEASE_ENABLED=false
WEBHOOK_ISSUES_ENABLED=false
WEBHOOK_ISSUE_COMMENT_ENABLED=false
WEBHOOK_GLOBAL_ENABLED=false
```

#### Command Configuration (`commands.json`)

Commands are configured in a JSON file with the following structure:

```json
{
  "commands": {
    "push": [
      {
        "name": "deploy-production",
        "description": "Deploy to production on main branch",
        "type": "shell",
        "command": "/path/to/deploy.sh",
        "args": ["{{branch}}", "{{repo}}", "{{pusher}}"],
        "cwd": "/workspace",
        "timeout": 600000,
        "filterBranch": "main"
      }
    ],
    "issues": [
      {
        "name": "process-issue",
        "description": "Process issue with Node.js script",
        "type": "node",
        "command": "./scripts/process-issue.js",
        "args": ["--repo", "{{repo}}", "--issue", "{{issue_number}}"],
        "cwd": null,
        "timeout": 300000,
        "filterBranch": null
      }
    ]
  }
}
```

**Command Fields:**
- `name` - Unique identifier for the command
- `description` - Human-readable description
- `type` - Either `"shell"` (bash script) or `"node"` (Node.js script)
- `command` - The command or script to execute
- `args` - Array of arguments (supports variable substitution)
- `cwd` - Working directory (null uses project root)
- `timeout` - Timeout in milliseconds
- `filterBranch` - Only run for specific branch (null = all branches)

**Available Variables:**
- `{{repo}}` - Repository name (e.g., "my-repo")
- `{{full_repo}}` - Full repository name (e.g., "user/my-repo")
- `{{repo_owner}}` - Repository owner username (e.g., "user")
- `{{branch}}` - Branch name (e.g., "main", "feature/new-feature")
- `{{pusher}}` - Username of person who triggered the event
- `{{event}}` - Event type (e.g., "push", "pull_request")
- `{{commit}}` - Latest commit hash (short, for push events)
- `{{commit_msg}}` - Latest commit message (for push events)
- `{{pr_number}}` - Pull request number (for PR events)
- `{{pr_action}}` - Pull request action (opened, closed, etc.)
- `{{tag}}` - Tag name (for create/delete tag events)
- `{{ref_type}}` - "branch" or "tag"
- `{{issue_number}}` - Issue number (for issue events)
- `{{issue_title}}` - Issue title (for issue events)
- `{{issue_action}}` - Issue action (opened, closed, reopened, etc.)
- `{{issue_body}}` - Issue description/body (for issue events)
- `{{issue_assignee}}` - Username of the person assigned to the issue (for issue events)
- `{{comment_body}}` - Comment text (for issue_comment events)

**Supported Event Types:**
- `push` - Push events
- `pull_request` - Pull request events
- `create` - Branch/tag creation
- `delete` - Branch/tag deletion
- `release` - Release events
- `issues` - Issue events (opened, closed, reopened, etc.)
- `issue_comment` - Issue comment events
- `global` - All events

### Endpoints

- `POST /webhook` - Webhook endpoint
- `GET /health` - Health check endpoint

## Job Queue System

The webhook server uses a persistent job queue to ensure reliable and sequential command execution:

### How It Works

1. **Webhook Received**: When a webhook arrives, it's immediately accepted and added to the queue
2. **Quick Response**: The server responds to Gogs instantly (no timeout issues)
3. **Sequential Processing**: Jobs are executed one at a time in FIFO (first-in-first-out) order
4. **Persistence**: Queue state is saved to `queue.json` after every change
5. **Crash Recovery**: If the server crashes or restarts, pending jobs are automatically resumed

### Benefits

- **No Lost Webhooks**: Even if the server crashes, queued jobs are preserved and executed after restart
- **No Concurrent Execution**: Prevents conflicts when multiple webhooks trigger deployment scripts
- **Handle Bursts**: Can accept many webhooks quickly while processing them sequentially
- **Reliable**: Long-running commands won't block new webhook deliveries

### Queue File

The queue state is stored in `queue.json` in the project root:

```json
{
  "queue": [
    {
      "id": 1,
      "eventType": "push",
      "status": "pending",
      "createdAt": "2025-10-28T12:00:00.000Z"
    }
  ],
  "jobIdCounter": 5,
  "lastSaved": "2025-10-28T12:05:00.000Z"
}
```

This file is automatically managed and should not be manually edited. It's excluded from git via `.gitignore`.

## Real-World Examples

### Example 1: Auto-deploy on push to main

**.env:**
```env
WEBHOOK_PUSH_ENABLED=true
```

**commands.json:**
```json
{
  "commands": {
    "push": [
      {
        "name": "deploy-production",
        "description": "Deploy to production on main branch",
        "type": "shell",
        "command": "/home/deploy/deploy.sh",
        "args": ["{{repo}}", "{{branch}}", "{{commit}}"],
        "cwd": null,
        "timeout": 600000,
        "filterBranch": "main"
      }
    ]
  }
}
```

**deploy.sh:**
```bash
#!/bin/bash
REPO=$1
BRANCH=$2
COMMIT=$3

echo "Deploying $REPO from $BRANCH (commit: $COMMIT)"
cd /var/www/$REPO
git pull origin $BRANCH
npm install
npm run build
systemctl restart $REPO
```

### Example 2: Send notification on any webhook

**.env:**
```env
WEBHOOK_GLOBAL_ENABLED=true
```

**commands.json:**
```json
{
  "commands": {
    "global": [
      {
        "name": "slack-notification",
        "description": "Send Slack notification for all events",
        "type": "shell",
        "command": "curl",
        "args": ["-X", "POST", "https://api.slack.com/webhook", "-d", "{\"text\":\"{{event}} in {{repo}} by {{pusher}}\"}"],
        "cwd": null,
        "timeout": 30000,
        "filterBranch": null
      }
    ]
  }
}
```

### Example 3: Run tests on pull request with Node.js

**.env:**
```env
WEBHOOK_PULL_REQUEST_ENABLED=true
```

**commands.json:**
```json
{
  "commands": {
    "pull_request": [
      {
        "name": "run-tests",
        "description": "Run automated tests on pull request",
        "type": "node",
        "command": "./scripts/run-tests.js",
        "args": ["--repo", "{{repo}}", "--pr", "{{pr_number}}", "--author", "{{pusher}}"],
        "cwd": "/home/ci",
        "timeout": 900000,
        "filterBranch": null
      }
    ]
  }
}
```

## Extending with Callbacks

The server is designed to be easily extended with custom callbacks. See `examples/with-callbacks.js` for a complete example.

### Register Event-Specific Callbacks

```javascript
import { WebhookServer } from './src/server.js';

const server = new WebhookServer({ port: 3000 });
const handler = server.getHandler();

// Handle push events
handler.on('push', async (payload, headers) => {
  console.log('Push to:', payload.repository.name);
  console.log('Commits:', payload.commits.length);
  // Your custom logic here
});

// Handle pull request events
handler.on('pull_request', async (payload, headers) => {
  console.log('PR:', payload.action);
  // Your custom logic here
});

server.start();
```

### Register Global Callbacks

```javascript
// Handle all events
handler.onAny(async (eventType, payload, headers) => {
  console.log('Received event:', eventType);
  // Send to analytics, external logging, etc.
});
```

### Run the Example

```bash
node examples/with-callbacks.js
```

## Gogs Webhook Configuration

1. Go to your Gogs repository settings
2. Navigate to Webhooks → Add Webhook → Gogs
3. Configure:
   - **Payload URL**: `http://your-server:3000/webhook`
   - **Content Type**: `application/json`
   - **Secret**: (optional) your webhook secret
   - **Events**: Select which events to receive
4. Click "Add Webhook"

### Supported Events

- `push` - Repository push
- `create` - Branch or tag creation
- `delete` - Branch or tag deletion
- `pull_request` - Pull request actions
- `issues` - Issue actions
- `issue_comment` - Issue comment actions
- `release` - Release actions

## Project Structure

```
.
├── src/
│   ├── index.js           # Main entry point
│   ├── server.js          # HTTP server implementation
│   ├── webhookHandler.js  # Webhook processing and callbacks
│   ├── jobQueue.js        # Persistent job queue with FIFO processing
│   ├── commandExecutor.js # Command execution with variable substitution
│   ├── config.js          # Configuration loader (.env and commands.json)
│   └── logger.js          # Logging utility
├── examples/
│   └── with-callbacks.js  # Example with custom callbacks
├── .env.example           # Example environment configuration
├── commands.json.example  # Example command configuration
├── .env                   # Your environment configuration (not in git)
├── commands.json          # Your command configuration (not in git)
├── queue.json             # Queue state (auto-generated, gitignored)
├── package.json
└── README.md
```

## Architecture

### WebhookServer (`src/server.js`)
- Creates HTTP server
- Handles routing and request parsing
- Manages webhook verification
- Delegates webhook processing to handler

### WebhookHandler (`src/webhookHandler.js`)
- Manages callback registration
- Executes callbacks for events
- Supports event-specific and global callbacks
- Provides error handling for callbacks

### JobQueue (`src/jobQueue.js`)
- Manages persistent job queue with FIFO processing
- Ensures only one job executes at a time
- Persists queue state to `queue.json`
- Handles crash recovery and job resumption
- Provides queue statistics and status

### CommandExecutor (`src/commandExecutor.js`)
- Executes shell and Node.js commands on webhook events
- Performs variable substitution in commands and arguments
- Supports both shell scripts and Node.js scripts
- Handles command timeouts and errors
- Extracts webhook payload data

### Logger (`src/logger.js`)
- Formats and colorizes console output
- Provides structured logging methods
- Handles timestamp formatting

### Config (`src/config.js`)
- Loads and parses .env file and commands.json
- Provides configuration access methods
- Merges environment variables with file config
- Supports backward compatibility with legacy .env commands

## Testing

You can test the webhook server using curl:

```bash
# Test health check
curl http://localhost:3000/health

# Test webhook with push event
curl -X POST http://localhost:3000/webhook \
  -H "Content-Type: application/json" \
  -H "X-Gogs-Event: push" \
  -H "X-Gogs-Delivery: 12345" \
  -d '{
    "ref": "refs/heads/main",
    "repository": {
      "name": "test-repo",
      "full_name": "user/test-repo"
    },
    "pusher": {
      "username": "testuser"
    },
    "commits": [
      {
        "id": "abc123",
        "message": "Test commit"
      }
    ]
  }'
```

## License

ISC