job-watcher

job-watcher is a Rust library for running and monitoring periodic background tasks. It provides a simple framework for defining, configuring, and observing jobs, and can expose a web-based status page to visualize their health.

Features

• Periodic Task Scheduling: Easily define tasks that run at regular intervals.
• Centralized Configuration: Configure task-specific properties like execution delay, out-of-date thresholds, and retry logic.
• Health Monitoring: Automatically tracks successes, failures, and whether a task has become "out of date" (i.e., not successfully completed within a configured timeframe).
• Web Status Page: Serves an HTML status page showing the state of all watched tasks, including recent output, execution counts, and environment details.
• Custom Alerting: Implement your own logic to determine when a task failure should trigger an alert.
• Stateful Tasks: Tasks can access their own execution history (e.g., success/failure counts) via a Heartbeat mechanism to make stateful decisions.

Quick Start

Here's how to get started with job-watcher

1. Define your Application Context

First, create a struct for your application and implement the WatcherAppContext trait. This trait provides configuration and top-level information to the watcher.

2. Define your Watched Tasks

Next, create structs for your background jobs and implement the WatchedTask trait. The run_single method contains the logic for your job.

Here we define a simple, stateless task, and a second, stateful task that uses the Heartbeat to fail after a certain number

3. Build and Run the Watcher

Finally, in your main function, use the AppBuilder to register your tasks and start the watcher. See the code under examples directory for more details.