How We Monitor APIs: A Real-World Example Using Node.js

APIs are the backbone of modern applications. But just because your API returns a 200 OK doesn't mean everything's working fine.

Slow responses, partial timeouts, or degraded performance can silently break your user experience. In this post, we'll show you:

• How to monitor an API using a simple Node.js example
• Which metrics matter most
• How Watchman Tower handles API monitoring effortlessly

A Basic Health Check in Node.js

const fetch = require('node-fetch');
async function checkAPI() {  
const start = Date.now(); 
try {   
	const res = await fetch('https://api.myapp.com/health');
    const duration = Date.now() - start;
    if (!res.ok) {    
        console.error(`API returned error: ${res.status}`);    
    } else {
        console.log(`API healthy. Response time: ${duration}ms`);   
     }  
} catch (err) {
     console.error('API is down or unreachable.', err);
}
                   
checkAPI();

✅ Checks uptime
✅ Measures response time
❌ But only works manually — and locally

Why Manual Monitoring Falls Short

Manual checks are unreliable. You need real-time monitoring, historical data, and alerts when things go wrong. That’s where Watchman Tower helps.

How Watchman Tower Handles API Monitoring

• Setup takes less than 5 minutes
• Endpoints are checked from 3 regions on every plan
• Real-time email and push alerts on every plan, plus Slack and SMS on Team and Stack
• All response times are logged and visualized

Example:
🔔 GET https://api.myapp.com/health exceeded its 10s timeout → monitor marked down → alert sent

Custom Intervals & Timeouts

You can define how often to run checks and set custom timeout durations. Depending on your plan, checks run anywhere from every 30 seconds to every 5 minutes (every 5 minutes on Free).

Timeout settings are fully customizable, allowing you to decide when an API should be marked as “down.”

When Does an API Count as Down?

Today, alerts are driven by failures, not latency thresholds:

• An error status code or a request that exceeds your timeout marks the monitor as down
• Checks run from 3 regions on every plan, including Free

If slow responses matter to you, set a tighter timeout—anything slower than that limit is treated as a failure.

Try It Yourself

No bloated configs. No YAML. Just fast, developer-friendly monitoring.

Start Monitoring Your APIs Now
🚀 Free plan – no credit card required. Paid plans include a 14-day trial.