Concepts Checks HTTP

HTTP Check

The HTTP check sends an HTTP request to a URL and verifies the response. It's the most common check type — use it to confirm your web app, API, or any HTTP endpoint is responding correctly.

Source: HttpCheckExecutor.cs · HttpCheckData.cs

What it verifies

• The server responds within the timeout (default 5 seconds)
• The response status code matches what you expect (default: any 2xx)
• Optionally, the response body contains a specific string

Common use cases

API health endpoint

{
  "url": "https://api.example.com/health",
  "method": "GET",
  "expectedStatusCodes": [200]
}

Authenticated endpoint

{
  "url": "https://api.example.com/internal/status",
  "method": "GET",
  "headers": { "Authorization": "Bearer my-token" },
  "expectedStatusCodes": [200],
  "expectedBodyContains": "\"status\":\"ok\""
}

POST endpoint

{
  "url": "https://api.example.com/ping",
  "method": "POST",
  "body": "{\"check\": true}",
  "headers": { "Content-Type": "application/json" },
  "expectedStatusCodes": [200, 201]
}

Configuration

Field	Default	Description
url	—	The URL to request (required)
method	GET	HTTP method
headers	—	Key-value pairs added to the request
body	—	Request body (use with POST/PUT)
timeout	5000	Milliseconds before the request is aborted
followRedirects	true	Whether to follow HTTP redirects
expectedStatusCodes	—	List of accepted status codes; empty = any 2xx
expectedBodyContains	—	String that must appear in the response body

Statuses

Status	When
UP	Response received, status code matches, body check passes
DOWN	Wrong status code, body doesn't contain expected string, or request timed out
FAILURE	URL is empty or an unexpected error occurred during setup

Latency

Measured from when the request is sent to when response headers are received (not the full body). This reflects server response time without body download overhead.

Related

• Checks — common settings (schedule, thresholds, criticality)
• SSL Check — pair with HTTP to also monitor your certificate