Test webhook connectivity

The connectivity test sends one request to a webhook URL and reports what came back. It answers a narrow question: can MockGateway reach this address at all? Run it before wiring a webhook to a gateway, so a missed payment notification is not how you find out.

Before you start

• The URL you want to check
• Any headers your endpoint needs

Run the test

1. Open the webhook, or start creating one.
2. Fill in the URL and any headers.
3. Trigger the connectivity test. The create screen says Test connectivity before saving for a reason.
4. Read the result.

What the results mean

Message	What happened
Connection successful.	Your endpoint answered with a 2xx status.
Request failed with status 404.	The endpoint was reached but answered outside 2xx. The number is what it returned.
Could not connect to the URL. Check that the URL is correct and reachable.	No connection at all. Wrong host, closed port, DNS failure, or an address that only exists on your own machine.

The request carries the user agent BackendSimulator-WebhookTest/1.0, worth allowing through if your endpoint filters on it. It gives up after ten seconds.

Check it worked

Connection successful. is what you want. If your endpoint logs incoming requests, the test should appear there with that user agent.

If it didn't work

Localhost never works.
http://localhost:3000 and 127.0.0.1 mean this machine to whatever makes the request. From MockGateway's side that is not your laptop. Use a tunnel that gives your local server a public URL, and test that instead.

A status you did not expect.
The test sends the method you configured. An endpoint that only takes POST answers a GET test with 405 even though it is perfectly healthy. Match the method.

401 or 403.
The test sends the headers on the webhook. If your endpoint wants a key the webhook does not carry, add it under Authentication & Headers.

It times out.
Anything past ten seconds counts as a failure. Real deliveries face the same limit, so an endpoint doing slow work inline is worth splitting: acknowledge first, process after.

The request comes from MockGateway, not from you

The test is an outbound call made by MockGateway's servers, the same as a real delivery. If your endpoint sits behind an IP allowlist, a firewall rule, or a VPN, your own browser reaching the URL proves nothing — the allowlist has to admit MockGateway.

That is the most common reason a URL works when you paste it into a tab and fails here.

What the test does not prove

A pass means the address answers. It says nothing about whether your handler understands the payload, checks the signature, or updates the right order. Only a real payment exercises those, so run one once the connection is good.