A health check is like a routine check-up for your system or component. It's a way to make sure everything is running as expected and there are no underlying issues that could cause problems down the line. Just like going to the doctor for a regular check-up, running a health check on your software helps you catch any potential issues early on.
For example, let's say you have a web application. You can implement a health check endpoint that returns a simple status like "OK" to indicate that the application is up and running. This endpoint can be monitored by a tool like Prometheus to ensure that the application is healthy and responding as expected. If the health check fails, it could trigger an incident management process to investigate and resolve the issue.
In JavaScript, a basic health check endpoint for a Node.js application might look like this:
app.get('/health', (req, res) => {
res.status(200).send('OK');
});