# Farm Control Scheduler

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A background service for Farm Control ERP that fires time-sensitive events on model objects once their scheduled date/time has passed.

## Features

- Scans configured models for scheduled properties (e.g. a "publish at" or "expires at" date) and picks up any that are now due.
- Runs the scheduling loop on a dedicated worker thread, so checks never block the main application event loop.
- Calls `onSchedulerEvent(property, value)` on the relevant model instance once its scheduled time arrives.

## How it works

1. On startup, `SchedulerManager` inspects every registered model for a `scheduledProperties` definition and queries the database for any matching objects that are due (or already overdue).
2. Each match is wrapped in a `Scheduler` (`id`, `objectType`, `object`, `property`, `value`) and added to the manager's schedulers list.
3. A worker thread (`schedulerWorker.js`) polls the list on an interval, comparing each scheduler's `value` against the current date/time.
4. When a scheduler is due, the worker notifies the main thread, which calls `object.onSchedulerEvent(property, value)` and removes the scheduler from the list.

Models opt in to this behaviour by defining `scheduledProperties` on their Mongoose schema and implementing an `onSchedulerEvent(property, value)` method to handle the callback.

## Prerequisites

- Node.js (v16 or higher)
- MongoDB server
- Redis server

## Installation

1. Clone the repository
2. Install dependencies:
   ```bash
   npm install
   ```

## Configuration

The application uses `config.json` for configuration. At minimum it expects a `server` block controlling logging, plus connection details for MongoDB and Redis:

```json
{
  "server": {
    "logLevel": "debug"
  },
  "mongo": {
    "uri": "mongodb://localhost:27017/farmcontrol"
  },
  "redis": {
    "host": "localhost",
    "port": 6379
  }
}
```

See `config.js` for the full set of supported options.

## Running the Application

### Development

```bash
npm run dev
```

### Production

```bash
npm start
```

## Logging

The application uses [log4js](https://log4js-node.github.io/log4js-node/) for logging. Set the log level under `server.logLevel` in your configuration:

```json
{
  "server": {
    "logLevel": "debug"
  }
}
```

Available log levels (least to most verbose): `error`, `warn`, `info`, `debug`, `trace`.