Types of tests

Four layers of verification

CyberApis performs four types of tests that together provide a complete picture of your website's health. Each checks a different aspect of operation.

1. Uptime check

The most basic test. The system sends an HTTP GET request to your URL and checks the response code.

• OK: 2xx response code (200, 201, etc.) — the site is reachable.
• ERROR: 4xx, 5xx code, timeout or no response — the site is down.
• Response time is measured in milliseconds and recorded in history.

2. Content check

An optional test that checks whether expected text is present on the page. You configure this when adding a site to monitoring.

• Useful for detecting situations where the page responds (200 code) but its content is incorrect.
• Example: you check if the homepage contains the phrase "Welcome to our store". If the phrase disappears — you get an alert.
• Text is searched in the entire HTML response, not just visible content.

3. Sanity check

Automatic page analysis looking for error indicators. The system checks if the response is:

• An empty page (no meaningful HTML content).
• A PHP error message (e.g. "Fatal error", "Warning", "Notice").
• A server error page (500 Internal Server Error, 503 Service Unavailable).
• A page with significantly truncated content (which may indicate partial loading).

This test runs automatically and requires no configuration.

4. Render probe

The most advanced test. Uses Browsershot + Puppeteer (headless Chrome) to:

• Fully render the page (execute JavaScript, load CSS).
• Take a screenshot at 1920x1080 resolution.
• Compare the current screenshot with the previous one to detect visual regressions.
• Detect CSS style breakage or rendering errors.

Render probe is optional — it can be enabled for selected sites. Because it uses a Chrome browser, this test consumes more server resources and takes longer than the others.