Mock JSON endpoint returning HTTP 422

Live demo endpoint

Any method, any path. Returns 422 Unprocessable Content with Content-Type: application/json. OPTIONS returns 204 with CORS headers.

Call it with curl

curl -i https://demo-json-422.supercrontab.com/

Call it with fetch

const res = await fetch("https://demo-json-422.supercrontab.com/");
console.log(res.status); // 422
const body = await res.json();

What HTTP 422 Unprocessable Content means

When you see it

The request was well formed but failed validation: an email without @, a date in the past, a value out of range.

What a client should do

Show the validation errors to the user and fix the payload. Retrying the same body cannot succeed.

Retry?

No

Sample response body

{"ok":true,"id":42,"items":["alpha","beta","gamma"]}

The default for REST APIs. Parse it with response.json() and check the ok field.

Questions